Patent Description:
As the field of microfluidics continues to progress, microfluidic devices have become convenient platforms for processing and manipulating micro-objects such as biological cells. Electrokinetic microfluidic devices, such as optically actuated electrokinetic microfluidic devices, offer some desirable capabilities, including the ability to select and manipulate individual micro-objects. Such microfluidic devices require various inputs (e.g., fluid, pressure, vacuum, heat, cooling, light, etc.) to function. Some embodiments of the present invention are directed to systems useful for operating electrokinetic microfluidic devices, including optically actuated electrokinetic microfluidic devices. <CIT> is prior art.

According to the invention, a system for operating an electrokinetic device is provided, the system including a support configured to hold and operatively couple with an electrokinetic device, an electrical signal generation subsystem configured to apply a biasing voltage across a pair of electrodes in the electrokinetic device when the electrokinetic device is held by, and operatively coupled with, the support, and a light modulating subsystem configured to emit structured light onto the electrokinetic device when the electrokinetic device is held by, and operatively coupled with, the support. The support includes a socket configured to receive and interface with the electrokinetic device. The electrical signal generation subsystem preferably includes a waveform generator configured to generate a biasing voltage waveform to be applied across the electrode pair when the electrokinetic device is held by, and operatively coupled with, the support. The electrical signal generation subsystem may further include a waveform amplification circuit configured to amplify the biasing waveform generated by the waveform generator, and/or an oscilloscope configured to measure the biasing voltage waveform, and wherein data from the measurement is provided as feedback to the waveform generator. By way of example, and without limitation, the electrokinetic device may be an optically actuated electrokinetic device.

According to the invention, the system includes a thermal control subsystem configured to regulate a temperature of the electrokinetic device when the electrokinetic device is held by, and operatively coupled with, the support. The thermal control subsystem may include a thermoelectric power module, a Peltier thermoelectric device, and a cooling unit, wherein the thermoelectric power module is configured to regulate a temperature of the Peltier thermoelectric device, and wherein the Peltier thermoelectric device is interposed between a surface of the electrokinetic device and a surface of the cooling unit. In some embodiments, the cooling unit may include a liquid cooling device, a cooling block, and a liquid path configured to circulate cooled liquid between the liquid cooling device and the cooling block, wherein the cooling block includes the surface of the cooling unit, and the respective Peltier thermoelectric device and the thermoelectric power module may be mounted on and/or integrated with the support.

According to the invention, the support includes a microprocessor that controls one or both of the electrical signal generation subsystem and the thermoelectric power module. For example, the support may include a printed circuit board (PCB), and wherein at least one of the electrical signal generation subsystem, the thermoelectric power module, and the microprocessor are mounted on and/or integrated with the PCB. The system may further include an external computational device operatively coupled with the microprocessor, wherein the external computational device includes a graphical user interface configured to receive operator input and for processing and transmitting the operator input to the microprocessor for controlling one or both of the electrical signal generation subsystem and the thermal control subsystem. For example, the microprocessor may be configured to transmit to the external computational device data and/or information sensed or received, or otherwise calculated based upon data or information sensed or received, from one or both of the electrical signal generation subsystem and the thermal control subsystem. In one such embodiment, the microprocessor and/or the external computational device are configured to measure and/or monitor an impedance of an electrical circuit across the electrodes of the electrokinetic device when the electrokinetic device is held by, and operatively coupled with, the support, wherein the microprocessor and/or the external computational device are configured to determine a flow volume of a fluid path based upon a detected change in the measured and/or monitored impedance of the electrical circuit, the fluid path including at least part of a microfluidic circuit within the electrokinetic device. The microprocessor and/or the external computational device may be additionally or alternatively configured to determine a height of an interior microfluidic chamber of the electrokinetic device based upon a detected change in the measured and/or monitored impedance of the electrical circuit, and/or be configured to determine one or more characteristics of chemical and/or biological material contained within the microfluidic circuit of the electrokinetic device based upon a detected change in the measured and/or monitored impedance of the electrical circuit.

In some embodiments, the support and/or the light modulating subsystem may be configured to be mounted on a light microscope. In other embodiments, the support and/or the light modulating subsystem are integral components of a light microscope.

According to the invention, the system includes a first fluid line having a distal end configured to be fluidically coupled to an inlet port of the electrokinetic device, and a second fluid line having a proximal end configured to be fluidically coupled to an outlet port of the electrokinetic device, respectively, when the electrokinetic device is held by, and operatively coupled with, the support. According to the invention, the system includes at least one thermally-controlled flow controller operatively coupled with one or both of the first and second fluid lines.

In some embodiments, the system includes a first thermally-controlled flow controller operatively coupled with one of the first fluid line and the second fluid line to selectively allow fluid to flow therethrough, wherein the first thermally-controlled flow controller may include a first thermally conductive interface thermally coupled with a flow segment of the first fluid line, and at least one flow control Peltier thermoelectric device configured to controllably lower or raise a temperature of the first thermally conductive interface sufficiently to controllably freeze or thaw fluid contained in the flow segment of the first fluid line and thereby selectively prevent or allow fluid to flow through into or out of the inlet port of the electrokinetic device through the first fluid line. The first thermally-controlled flow controller may include a first housing having a first passageway through which the flow segment of the first fluid line extends, the housing further containing the first thermally conductive interface and the at least one flow control Peltier thermoelectric device; and/or insulating material at least partially surrounding the flow segment of the first fluid line proximate the first thermally conductive interface. The system may include a second thermally-controlled flow controller operatively coupled with the other one of the first fluid line and the second fluid line to selectively allow fluid to flow therethrough, wherein the second thermally-controlled flow controller may include a second thermally conductive interface thermally coupled with a flow segment of the second fluid line, and at least one flow control Peltier thermoelectric device configured to controllably lower or raise a temperature of the second thermally conductive interface sufficiently to controllably freeze or thaw fluid contained in the flow segment of the second fluid line and thereby selectively prevent or allow fluid to flow out of or into the outlet port of the electrokinetic device. The second thermally-controlled flow controller may include a second housing having a second passageway through which the flow segment of the second fluid line extends, the housing further containing the second thermally conductive interface thermally coupled with the flow segment of the second fluid line, and the at least one flow control Peltier thermoelectric device configured to controllably lower or raise a temperature of the second thermally conductive interface; and/or insulating material at least partially surrounding the flow segment of the second fluid line proximate the second thermally conductive interface.

According to the invention, the system includes a thermally-controlled flow controller operatively coupled with the first and second fluid lines, the thermally-controlled flow controller including a thermally conductive interface having a first portion thermally coupled with a flow segment of the first fluid line, and a second portion thermally coupled with a flow segment of the second fluid line, and at least one flow-control Peltier thermoelectric device configured to controllably lower or raise a temperature of the thermally conductive interface sufficiently to controllably freeze or thaw fluid contained in the respective flow segments of the first and second fluid lines and thereby selectively prevent or allow fluid to flow through the first fluid line into the inlet port of the electrokinetic device, or from the outlet port of the electrokinetic device through the outflow fluid line. In such embodiments, the at least one flow-control Peltier thermoelectric device may include a first flow-control Peltier thermoelectric device thermally coupled to the first portion of the thermally conductive interface proximate the flow segment of the first fluid line, and a second flow-control Peltier thermoelectric device thermally coupled to the second portion of the thermally conductive interface proximate the flow segment of the second fluid line. The flow controller may include a housing having a first passageway through which the flow segment of the first fluid line extends, and a second passageway through which the flow segment of the outflow fluid line extends, wherein the thermally conductive interface is mounted in the housing, for example, wherein the housing defines a thermally insulating chamber in which the thermally conductive interface is mounted.

In various embodiments, the light modulating subsystem may include one or more of a digital mirror device (DMD), a microshutter array system (MSA), a liquid crystal display (LCD), a liquid crystal on silicon device (LCOS), a ferroelectric liquid crystal on silicon device (FLCOS), and a scanning laser device.

In exemplary embodiments, the light modulating subsystem includes a multi-input structure, such as a light pipe or a crossed dichroic prism (or "x-cube"). The light pipe can include a housing having a plurality of input apertures, each input aperture configured to receive light emitted from a respective light source, the housing further having an output aperture configured to emit light received through the input apertures; a first light propagation pathway extending within the housing from a first input aperture to the output aperture; a first dichroic filter positioned within the housing at an oblique angle across the first light propagation pathway, the first dichroic filter configured and positioned so that light received through the first light aperture passes through the first dichroic filter as it propagates along the first light propagation pathway to the output aperture; and a second light propagation pathway extending within the housing from a second input aperture to the first dichroic filter, the second propagation pathway and first dichroic filter configured and dimensioned so that light received through the second input aperture propagates along the second light propagation pathway and is reflected onto the first light propagation pathway to the output aperture by the first dichroic filter, wherein the respective input apertures, first and second light propagation pathways, first dichroic filter, and output aperture are sized, dimensioned and configured such that light emitted by at least one light source and received through at least one of the first and second input apertures is emitted at substantially uniform intensity out the output aperture. The light pipe may further include a second dichroic filter positioned within the housing at an oblique angle across the first light propagation pathway between the first dichroic filter and the output aperture, the second dichroic filter configured and positioned so that light received through the first and second light apertures passes through the second dichroic filter as the received light propagates along the first light propagation pathway to the output aperture, and a third light propagation pathway extending within the housing from a third input aperture to the second dichroic filter, the third propagation pathway and second dichroic filter configured and dimensioned so that light received through the third input aperture propagates along the third light propagation pathway and is reflected onto the first light propagation pathway to the output aperture by the second dichroic filter.

The light modulating subsystem may further include a first light source having an output optically coupled with the first input aperture of the light pipe, wherein the first light source may include a plurality of first light source emitting elements, which may emit light at a first narrowband wavelength. The light modulating subsystem may further include a second light source having an output optically coupled with the second input aperture of the light pipe, for example, with the second light source including a plurality of second light source emitting elements, which may emit light at the first narrowband wavelength or at a second narrowband wavelength different from the first narrowband wavelength. The plurality of first light source emitting elements and the plurality of second light source emitting elements preferably collectively include a first subset of one or more light emitting elements that emit light at the first narrowband wavelength, and a second subset of one or more light emitting elements that emit light at a second narrowband wavelength different from the first narrowband wavelength, such that light including one or both of the first narrowband wavelength and second narrowband wavelength may be controllably emitted out the light pipe output aperture by selectively activating one or both of the plurality of first light source emitting elements and the plurality of second light source emitting elements. In this manner, light emitted by the first subset of light emitting elements and received through the first and/or second input apertures is emitted out the output aperture of the light pipe at a first substantially uniform intensity, and light emitted by the second subset of light emitting elements and received through the first and/or second input apertures is emitted out the output aperture at a second substantially uniform intensity, wherein the first substantially uniform intensity may be different from the second substantially uniform intensity.

By way of non-limiting examples, the first narrowband wave length and the second narrowband wavelength may be selected from the group consisting of approximately <NUM>, approximately <NUM>, and approximately <NUM>. In some embodiments, the plurality of light emitting elements of the first light source may include or consist of all of the first subset of light emitting elements, and the plurality of light emitting elements of the second light source may include or consist of all of the second subset of light emitting elements.

The light modulating subsystem may further include a third light source having an output optically coupled with the third input aperture of the light pipe, wherein the third light source may include a plurality of third light source emitting elements, for example, wherein one or more of the plurality of third light source emitting elements emits light at the first narrowband wavelength, the second narrowband wavelength, or a third narrowband wavelength different from each of the first and second narrowband wavelengths. In such embodiments, the plurality of first light source emitting elements, the plurality of second light source emitting elements, and the plurality of third light source emitting elements collectively including a first subset of one or more light emitting elements that emit light at the first narrowband wavelength, a second subset of one or more light emitting elements that emit light at the second narrowband wavelength different from the first narrowband wavelength, and a third subset of one or more light emitting elements that emit light at a third narrowband wavelength different from each of the first and second narrowband wavelengths, such that light including one or more of the first narrowband wavelength, second narrowband wavelength, and third narrowband wavelength may be controllably emitted out the light pipe output aperture by selectively activating one or more of the first, second and third subsets of light emitting elements. In one such embodiment, light emitted by the first subset of light emitting elements and received through any of the first, second and third input apertures is emitted out the output aperture at a first substantially uniform intensity, light emitted by the second subset of light emitting elements and received through any of the first, second and third input apertures is emitted out the output aperture at a second substantially uniform intensity, and light emitted by the third subset of light emitting elements and received through any of the first, second and third input apertures is emitted out the output aperture at a third substantially uniform intensity, wherein the first substantially uniform intensity may be different from one or both of the second substantially uniform intensity and third substantially uniform intensity. In various such embodiments, the first narrowband wave length may be approximately <NUM>, the second narrowband wavelength may be approximately <NUM>, and the third narrowband wavelength may be approximately <NUM>. In some such embodiments, the plurality of light emitting elements of the first light source may include or consist of all of the first subset of light emitting elements, the plurality of light emitting elements of the second light source may include or consist of all of the second subset of light emitting elements, and the plurality of light emitting elements of the third light source may include or consist of all of the third subset of light emitting elements.

In accordance with another aspect, embodiments of a microscope configured for operating an electrokinetic device are disclosed, wherein the microscope includes a support configured to hold and operatively couple with an electrokinetic device; a light modulating subsystem configured to emit structured light; and an optical train, wherein when the electrokinetic device is held by, and operatively coupled with, the support, the optical train is configured to: (<NUM>) focus structured light emitted by the light modulating subsystem onto at least a first region of the electrokinetic device, (<NUM>) focus unstructured light emitted by an unstructured light source onto at least a second region of the electrokinetic device, and (<NUM>) capture reflected and/or emitted light from the electrokinetic device and direct the captured light to a detector. In preferred embodiments, the microscope also includes the detector, which may be an eye piece and/or an imaging device. The light modulating subsystem may include one or more of a digital mirror device (DMD) or a microshutter array system (MSA), a liquid crystal display (LCD), a liquid crystal on silicon device (LCOS), a ferroelectric liquid crystal on silicon device (FLCOS), and a scanning laser device, wherein the microscope preferably includes a controller for controlling the light modulating subsystem. The optical train may include an objective which is configured to focus the structured light on the first region of the microfluidic device and/or the unstructured light on the second region of the microfluidic device, and wherein the objective is selected from the group including: a 10x objective; a 5x objective; a 4x objective; and a 2x objective.

In some embodiments, the optical train includes a dichroic filter configured to substantially prevent structured light emitted by the light modulating subsystem (and reflected by the electrokinetic device) from reaching the detector.

In some embodiments, the optical train includes a dichroic filter configured to balance an amount of visible structured light emitted by the light modulating subsystem (and reflected by the electrokinetic device) and an amount of visible unstructured light emitted by the unstructured light source (and reflected by the electrokinetic device) that reaches the detector.

In some embodiments, the light modulating subsystem emits structured white light.

In some embodiments, the light modulating subsystem includes one or more of a Mercury, a Xenon arc lamp, and one or more LEDs. In certain embodiments, the light modulating subsystem includes a multi-input structure, such as a light pipe or a crossed dichroic prism (or "x-cube").

In some embodiments, the unstructured light source includes one or more LEDs, for example, wherein the unstructured light source emits light having a wavelength of approximately <NUM> or shorter (e.g., blue light), wherein the optical train preferably includes a dichroic filter configured to at least partially filter out visible light having a wavelength longer than <NUM>.

In some embodiments, the unstructured light source includes one or more LEDs, for example, wherein the unstructured light source emits light having a wavelength of approximately <NUM> or shorter (e.g., red light), wherein the optical train preferably includes a dichroic filter configured to at least partially filter out visible light having a wavelength shorter than <NUM>.

In exemplary embodiments, the microscope support includes one or both of an integrated electrical signal generation subsystem configured to apply a biasing voltage across a pair of electrodes in the electrokinetic device, and a thermal control subsystem configured to regulate a temperature of the electrokinetic device, respectively, when the device is held by, and operatively coupled with, the support, the support. By way of example, and without limitation, the electrokinetic device may be an optically actuated electrokinetic device.

In accordance with yet another aspect, embodiments of a multi-input light pipe are disclosed. In an exemplary embodiment, the light pipe includes a light pipe housing having a plurality of input apertures, each input aperture configured to receive light emitted from a respective light source, the housing further having an output aperture configured to emit light received through the input apertures; a first light propagation pathway extending within the housing from a first input aperture to the output aperture; a first dichroic filter positioned within the housing at an oblique angle across the first light propagation pathway, the first dichroic filter configured and positioned so that light received through the first light aperture passes through the first dichroic filter as it propagates along the first light propagation pathway to the output aperture; and a second light propagation pathway extending within the housing from a second input aperture to the first dichroic filter, the second propagation pathway and first dichroic filter configured and dimensioned so that light received through the second input aperture propagates along the second light propagation pathway and is reflected onto the first light propagation pathway to the output aperture by the first dichroic filter, wherein the respective input apertures, first and second light propagation pathways, first dichroic filter, and output aperture are sized, dimensioned and configured such that light emitted by at least one light source and received through at least one of the first and second input apertures is emitted at substantially uniform intensity out the output aperture. The light pipe may also include a second dichroic filter positioned within the housing at an oblique angle across the first light propagation pathway between the first dichroic filter and the output aperture, the second dichroic filter configured and positioned so that light received through the first and second light apertures passes through the second dichroic filter as the received light propagates along the first light propagation pathway to the output aperture, and a third light propagation pathway extending within the housing from a third input aperture to the second dichroic filter, the third propagation pathway and second dichroic filter configured and dimensioned so that light received through the third input aperture propagates along the third light propagation pathway and is reflected onto the first light propagation pathway to the output aperture by the second dichroic filter,.

In accordance with still another aspect, embodiments of a light transmission system are disclosed, including the above-summarized light pipe and at least a first light source having an output optically coupled with the first input aperture of the light pipe. By way of example, the first light source may include a plurality of first light source emitting elements, wherein one or more first light source emitting elements may emit light at a first narrowband wavelength. The light transmission system may include a second light source having an output optically coupled with the second input aperture of the light pipe. By way of example, the second light source may include a plurality of second light source emitting elements, wherein the second light source emitting elements may emit light at the first narrowband wavelength or at a second narrowband wavelength different from the first narrowband wavelength,.

In one such embodiment, the plurality of first light source emitting elements and the plurality of second light source emitting elements collectively include a first subset of one or more light emitting elements that emit light at the first narrowband wavelength, and a second subset of one or more light emitting elements that emit light at a second narrowband wavelength different from the first narrowband wavelength, such that light including one or both of the first narrowband wavelength and second narrowband wavelength may be controllably emitted out the light pipe output aperture by selectively activating one or both of the first and second subsets of light emitting elements. In such embodiment, light emitted by the first subset of light emitting elements and received through the first and/or second input apertures may be emitted out the output aperture of the light pipe at a first substantially uniform intensity, and light emitted by the second subset of light emitting elements and received through the first and/or second input apertures is emitted out the output aperture at a second substantially uniform intensity, which may or may not be different from the first substantially uniform intensity. By way of non-limiting examples, the first narrowband wave length and the second narrowband wavelength may be selected from the group consisting of approximately <NUM>, approximately <NUM>, and approximately <NUM>. In some embodiments, the plurality of light emitting elements of the first light source may include or consist of all of the first subset of light emitting elements, and the plurality of light emitting elements of the second light source may include or consist of all of the second subset of light emitting elements.

The light transmission system may further include a third light source having an output optically coupled with the third input aperture of the light pipe, wherein the third light source may include a plurality of third light source emitting elements in which one or more of the plurality of third light source emitting elements emits light at the first narrowband wavelength, the second narrowband wavelength, or a third narrowband wavelength different from each of the first and second narrowband wavelengths. In one such embodiment of the light transmission system the plurality of first light source emitting elements, the plurality of second light source emitting elements, and the plurality of third light source emitting elements collectively include a first subset of one or more light emitting elements that emit light at a first narrowband wavelength, a second subset of one or more light emitting elements that emit light at a second narrowband wavelength different from the first narrowband wavelength, and a third subset of one or more light emitting elements that emit light at a third narrowband wavelength different from each of the first and second narrowband wavelengths, such that light including one or more of the first narrowband wavelength, second narrowband wavelength, and third narrowband wavelength may be controllably emitted out the light pipe output aperture by selectively activating one or more of the first, second and third subsets of light emitting elements. In this manner, light emitted by the first subset of light emitting elements and received through any of the first, second and third input apertures is emitted out the output aperture at a first substantially uniform intensity, light emitted by the second subset of light emitting elements and received through any of the first, second and third input apertures is emitted out the output aperture at a second substantially uniform intensity, and light emitted by the third subset of light emitting elements and received through any of the first, second and third input apertures is emitted out the output aperture at a third substantially uniform intensity, wherein the first substantially uniform intensity may or may not be different from one or both of the second substantially uniform intensity and third substantially uniform intensity. The plurality of light emitting elements of the first light source may include or consist of all of the first subset of light emitting elements, the plurality of light emitting elements of the second light source may include or consist of all of the second subset of light emitting elements, and the plurality of light emitting elements of the third light source may include or consist of all of the third subset of light emitting elements.

The drawings illustrate the design and utility of embodiments of the disclosed invention, in which similar elements are referred to by common reference numerals. These drawings are not necessarily drawn to scale. In order to better appreciate how the above-recited and other advantages and objects are obtained, a more particular description of the embodiments will be rendered, which are illustrated in the accompanying drawings. These drawings depict only typical embodiments of the disclosed invention and are not therefore to be considered limiting of its scope.

This specification describes exemplary embodiments and applications of the invention. The invention, however, is not limited to these exemplary embodiments and applications or to the manner in which the exemplary embodiments and applications operate or are described herein. Further, the figures may show simplified or partial views, and the dimensions of elements in the figures may be exaggerated or otherwise not in proportion. Moreover, elements of similar structures or functions are represented by like reference numerals throughout the figures. An aspect or an advantage described in conjunction with a particular embodiment is not necessarily limited to that embodiment, and can be practiced in any other embodiments even if not so illustrated.

As the terms "on," "attached to," "connected to," "coupled to," or similar words are used herein, one element (e.g., a material, a layer, a substrate, etc.) can be "on," "attached to," "connected to," or "coupled to" another element regardless of whether the one element is directly on, attached to, connected to, or coupled to the other element or there are one or more intervening elements between the one element and the other element. Also, directions (e.g., above, below, top, bottom, side, up, down, under, over, upper, lower, horizontal, vertical, "x," "y," "z," etc.), if provided, are relative and provided solely by way of example and for ease of illustration and discussion and not by way of limitation. In addition, where reference is made to a list of elements (e.g., elements a, b, c), such reference is intended to include any one of the listed elements by itself, any combination of less than all of the listed elements, and/or a combination of all of the listed elements.

As used herein, "substantially" means sufficient to work for the intended purpose. The term "substantially" thus allows for minor, insignificant variations from an absolute or perfect state, dimension, measurement, result, or the like such as would be expected by a person of ordinary skill in the field but that do not appreciably affect overall performance. When used with respect to numerical values or parameters or characteristics that can be expressed as numerical values, "substantially" means within ten percent. The term "ones" means more than one.

The term "about" generally refers to a range of numbers that one of skilled in the art would consider equivalent to the recited value (i.e., having the same function or result).

As used herein, the term "disposed" encompasses within its meaning "located.

As used herein, the singular forms "a", "an", and "the" include plural referents unless the content clearly dictates otherwise. As used herein, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

In some embodiments, a system of the invention can include a support (also known as a "nest") configured to hold an electrokinetic device and a light modulating subsystem configured to receive unstructured light and emit structured light.

The support can include, for example, a socket configured to interface with and/or hold an optically actuated electrokinetic device, a printed circuit board assembly (PCBA), an electrical signal generation subsystem, a thermal control subsystem, or any combination thereof.

In certain embodiments of the invention, the support includes a socket capable of interfacing with an electrokinetic device, such as an optically actuated electrokinetic device. An exemplary socket <NUM> is included in the support <NUM> of <FIG> and <FIG>. However, the shape and functionality of the socket <NUM> need not be exactly as shown in <FIG> and <FIG>. Rather, it can be adjusted as needed to match the size and type of electrokinetic device <NUM> with which the socket <NUM> is intended to interface. A variety of electrokinetic devices <NUM> are known in the art, including devices <NUM> having optically actuated configurations, such as an optoelectronic tweezer (OET) configuration and/or an opto-electrowetting (OEW) configuration. Examples of suitable OET configurations are illustrated in the following U. patent documents, as though set forth in full: <CIT>) (originally issued as <CIT>); and <CIT>). Examples of OEW configurations are illustrated in <CIT>) and <CIT> as though set forth in full. Yet another example of optically actuated electrokinetic device includes a combined OET/OEW configuration, examples of which are shown in <CIT>) and <CIT>) and their corresponding <CIT> and <CIT>, as though set forth in full.

The support <NUM> depicted in <FIG> and <FIG> also includes a base <NUM> and a cover <NUM> (omitted in <FIG>). The support <NUM> also includes a plurality of connectors: a first fluidic input/output <NUM>; a communications connection <NUM>; a power connection <NUM>; and a second fluidic input/output <NUM>. The first and second fluidic input/outputs <NUM>, <NUM> are configured to deliver a cooling fluid to and from a cooling block (shown in <FIG>) used to cool the electrokinetic device <NUM>. Whether the first and second fluidic input/outputs <NUM>, <NUM> are input or outputs depends on the direction of fluid flow through the support <NUM>. The first and second fluidic input/outputs <NUM>, <NUM> are fluidly coupled to the cooling block by first and second fluidic connectors <NUM>, <NUM> disposed in the support <NUM>. The communications connection <NUM> is configured to connect the support <NUM> with other components of the system for operating electrokinetic microfluidic devices, as described below. The power connection <NUM> is configured to provide power (e.g., electricity) to the support <NUM>.

In certain embodiments, the support <NUM> can include an integrated electrical generation subsystem <NUM>. The electrical generation subsystem <NUM> can be configured to apply a biasing voltage across a pair of electrodes in an electrokinetic device <NUM> that is being held by the support <NUM>. The ability to apply such a biasing voltage does not mean that a biasing voltage will be applied at all times when the electrokinetic device <NUM> is held by the support <NUM>. Rather, in most cases, the biasing voltage will be applied intermittently, e.g., only as needed to facilitate the generation of electrokinetic forces, such as dielectrophoresis or electro-wetting, or the measurement of complex impedance in the electrokinetic device <NUM>.

Typically, the electrical signal generation subsystem <NUM> will include a waveform generator <NUM>, as shown in <FIG>. The electrical generation subsystem <NUM> can further include a sensing module <NUM> (e.g., an oscilloscope) and/or a waveform amplification circuit <NUM> configured to amplify a waveform received from the waveform generator <NUM>. The sensing module <NUM>, if present, can be configured to measure the waveform supplied to the electrokinetic device <NUM> held by the support <NUM>. In certain embodiments, the sensing module <NUM> measures the waveform at a location proximal to the electrokinetic device <NUM> (and distal to the waveform generator <NUM>), thus ensuring greater accuracy in measuring the waveform actually applied to the electrokinetic device <NUM>. Data obtained from the sensing module <NUM> measurement can be, for example, provided as feedback to the waveform generator <NUM>, and the waveform generator <NUM> can be configured to adjust its output based on such feedback. An example of a suitable combined waveform generator <NUM> and sensing module <NUM> is the RED PITAYA™.

In certain embodiments, the support <NUM> can include a thermal control subsystem <NUM>. The thermal control subsystem <NUM> can be configured to regulate the temperature of an electrokinetic device <NUM> held by the support <NUM>. As shown in <FIG>, the thermal control subsystem <NUM> can include a Peltier thermoelectric device <NUM> and a proximal component of a cooling unit <NUM>. The Peltier thermoelectric device <NUM> can have a first surface <NUM> configured to interface with at least one surface of the electrokinetic device <NUM>. The cooling unit can include, for example, a cooling block <NUM>. A second surface <NUM> of the Peltier thermoelectric device <NUM> (e.g., a surface <NUM> opposite the first surface <NUM>) can be configured to interface with a surface of such a cooling block <NUM>. All or part of the cooling block <NUM> (e.g., a part that interfaces with the Peltier thermoelectric device <NUM>) can be made from a material having a high thermal conductivity. For example, the material can be a metal, such as aluminum. The cooling block <NUM> can be connected to a fluidic path <NUM> configured to circulate cooled fluid between a fluidic cooling device <NUM> and the cooling block <NUM>. The fluidic path <NUM> can include the fluidic input/outputs <NUM>, <NUM> and the fluidic connectors <NUM>, <NUM> described in connection with <FIG>. The Peltier thermoelectric device <NUM> and the cooling block <NUM> can be mounted on the support <NUM>.

The thermal control subsystem <NUM> can further include a thermoelectric power module <NUM>, as shown in <FIG>. The thermoelectric power module <NUM> can regulate the temperature of the Peltier thermoelectric device <NUM> so as to achieve a target temperature for the microfluidic device <NUM>. Feedback for the thermoelectric power module <NUM> can include a temperature value provided by an analog circuit <NUM>, such as shown in <FIG>. Alternatively, the feedback can be provided by a digital circuit (not shown). The Peltier thermoelectric device <NUM>, the cooling block <NUM>, and the thermoelectric power module <NUM> all can be mounted on the support <NUM>.

In certain embodiments, the support <NUM> can also include or interface with an environmental temperature monitor/regulator in addition to the thermal control subsystem <NUM>.

The analog circuit <NUM> depicted in <FIG> includes a resistor <NUM>, a thermistor <NUM>, and an analog input <NUM>. The analog input is operatively coupled to the electrical signal generation subsystem <NUM> (e.g., the sensing module <NUM> thereof) and provides a signal thereto that can be used to calculate the temperature of the electrokinetic device <NUM>. The thermistor <NUM> is configured such that its resistance may decrease in a known manner when the temperature of the thermistor <NUM> decreases and increase in a known manner when the temperature of the thermistor <NUM> increases. The analog circuit <NUM> is connected to a power source (not shown) which is configured to deliver a biasing voltage to electrode <NUM>. In one particular embodiment, the resistor <NUM> can have a resistance of about <NUM>,<NUM> ohms, the thermistor <NUM> can have a resistance of about <NUM>,<NUM> ohms at <NUM>, and the power source (e.g., a DC power source) can supply a biasing voltage of about <NUM> V. The analog circuit <NUM> is exemplary, and other systems can be used to provide a temperature value for feedback for the thermoelectric power module <NUM>.

In certain embodiments, the support <NUM> further comprises a controller <NUM> (e.g., a microprocessor). The controller <NUM> can be used to sense and/or control the electrical signal generation subsystem <NUM>. In addition, to the extent that the support <NUM> includes a thermal control subsystem <NUM>, the controller <NUM> can be used to sense and/or control the thermal control subsystem <NUM>. Examples of suitable controllers <NUM> include the ARDUINO™ microprocessors, such as the ARDUINO NANO™. The controller <NUM> can be configured to interface with an external controller (not shown), such as a computer or other computational device, via a plug/connector <NUM>. In certain embodiments, the external controller can include a graphical user interface (GUI) configured to sense and/or control the electrical signal generation subsystem <NUM>, the thermal control subsystem <NUM>, or both. An exemplary GUI <NUM>, which is configured to control both the electrical signal generation subsystem <NUM> and the thermal control subsystem <NUM>, is depicted in <FIG>.

In certain embodiments, the support <NUM> can include a printed circuit board (PCB) <NUM>. The electrical signal generation subsystem <NUM> can be mounted on and electrically integrated into the PCB <NUM>. Similarly, to the extent that the support <NUM> includes a controller <NUM> or a thermal control subsystem <NUM>, the controller <NUM> and/or the thermoelectric power module <NUM> can be mounted on and electrically integrated into the PCB <NUM>.

Thus, as shown in <FIG> and <FIG>, an exemplary support <NUM> can include a socket <NUM>, an interface <NUM>, a controller <NUM>, an electrical signal generation subsystem <NUM>, and a thermal control subsystem <NUM>, all of which are mounted on and electrically integrated into PCB <NUM>, thereby forming a printed circuit board assembly (PCBA) <NUM>. As discussed above, the socket <NUM> can be designed to hold an electrokinetic device <NUM> (or "consumable"), including an optically actuated electrokinetic device.

In certain specific embodiments, the electrical generation subsystem <NUM> can include a RED PITAYA™ waveform generator <NUM>/sensing module <NUM> and a waveform amplification circuit <NUM> that amplifies the waveform generated by the RED PITAYA™ waveform generator <NUM> and passes the amplified waveform (voltage) <NUM> to the electrokinetic device <NUM>. Both the RED PITAYA™ unit <NUM>, <NUM> and the waveform amplification circuit <NUM> can be electrically integrated into the PCB <NUM> as an electrical signal generation subsystem <NUM>, as shown in <FIG>. Moreover, the RED PITAYA™ unit <NUM>, <NUM> can be configured to measure the amplified voltage at the electrokinetic device <NUM> and then adjust its own output voltage as needed such that the measured voltage at the electrokinetic device <NUM> is the desired value. The amplification circuit <NUM> can have, for example, a +<NUM>. 5V to -<NUM>. 5V power supply generated by a pair of DC-DC converters mounted on the PCB <NUM>, resulting in a signal of up to <NUM> Vpp at the electrokinetic device <NUM>.

In certain specific embodiments, the support <NUM> includes a thermal control subsystem <NUM> (shown in <FIG>) having a Peltier thermoelectric device <NUM>, located between a liquid-cooled aluminum block <NUM> and the back side of the electrokinetic device <NUM>, a POLOLU™ thermoelectric power supply (not shown), and an ARDUINO NANO™ controller <NUM>. Feedback for the thermal control subsystem <NUM> can be an analog voltage divider circuit <NUM> (shown in <FIG>) which includes a resistor <NUM> (e.g. resistance 10kOhm+/∼<NUM>%, temperature coefficient +/-<NUM>-<NUM> ppm/C°) and a negative temperature coefficient thermistor <NUM> (nominal resistance 10kOhm+/-<NUM>%). The controller <NUM> can measure the voltage from the feedback circuit <NUM> and then use the calculated temperature value as input (e.g., to an on-board PID control loop algorithm) to drive both a directional and a pulse-width-modulated signal pin on the thermoelectric power module <NUM>, and thereby actuate the thermoelectric subsystem <NUM>. A liquid cooling unit <NUM> can be configured to pump fluid through the cooling path <NUM> located, in part, in the support <NUM> (e,g. , fluidic input/outputs <NUM>, <NUM> and the fluidic connectors <NUM>, <NUM>) and, in part, at the periphery of the support <NUM>.

In certain specific embodiments, the support <NUM> includes a serial port <NUM> and a Plink tool that together allow the RED PITAYA™ unit to communicate with an external computer. The serial port <NUM> can also allow the controller <NUM> to communicate with the external computer. Alternatively, a separate serial port (not shown) can be used to allow the controller <NUM> to communicate with the external computer. In other embodiments, the support <NUM> can include a wireless communication device configured to facilitate wireless communication between components of the support <NUM> (e.g., the controller <NUM> and/or the electrical generation subsystem <NUM>) and the external computer, which can include a portable computing device such as a cell phone, a PDA, or other handheld device. A GUI (e.g., such as shown in <FIG>) on the external computer can be configured for various functions, including, but not limited to, plotting temperature and waveform data, performing scaling calculations for output voltage adjustment, and updating the controller <NUM> and RED PITAYA™ device <NUM>, <NUM>.

In certain embodiments, the support <NUM> can also include or interface with an inductance/capacitance/resistance (LCR) meter configured to measure characteristics of the contents (e.g., fluidic contents) of the electrokinetic device <NUM>.

For example, the LCR meter can be configured to measure the complex impedance of a system, particularly the complex impedance of a fluid as it enters, is located within, and/or as it exits an electrokinetic device <NUM>. In some embodiments, the LCR meter can be connected to and/or integrated into a fluid line that carries fluid into or out of the electrokinetic device <NUM>. In other embodiments, the LCR meter can be connected to or an integral part of the electrical generation subsystem <NUM>. Thus, in certain specific embodiments, the RED PITAYA™ waveform generator <NUM> and sensing module <NUM> in the support <NUM> can be configured to function as an LCR meter. In certain embodiments, electrodes of the electrokinetic device <NUM> which are configured for use with the electrical generation subsystem <NUM> can also be configured for use with the LCR meter. Measuring the impedance of a system can determine various system characteristics and changes therein, such as the height of the fluidic circuit within the electrokinetic device <NUM>, changes in the salt content of fluid in the electrokinetic device <NUM> (which may correlate with the status of biological micro-objects therein), and the movement of specific volumes of fluids (having different impedances) through the electrokinetic device <NUM>.

In certain embodiments, measuring the impedance of a system can be used to accurately (i.e., close to the true value) and precisely (i.e., repeatably) detect a change from a first fluid in a system (i.e., the electrokinetic device <NUM>) to a second fluid in the system. For example, the first fluid could be deionized water (DI) and and the second fluid could be a saline solution (e.g.,, phosphate-buffered saline or "PBS"), or vice versa. Alternatively, the first fluid could be a saline solution (e.g., PBS) and the second fluid could be a cell culture medium having an impedance that is detectably different than the saline solution, or vice versa. In still other alternatives, the first fluid could be a first cell culture medium and the second fluid could be a second cell culture medium having an impedance that is detectably different than the first cell culture medium. <FIG> is a diagram depicting an impedance measurement circuit <NUM> for detecting the impedance of a system. The circuit <NUM> includes an output <NUM> from the waveform generator <NUM> of the electrical generation subsystem <NUM>, and two inputs <NUM>, <NUM> to the sensing module <NUM> of the electrical generation subsystem <NUM>. The circuit <NUM> also includes the electrokinetic device <NUM> (connected via the socket <NUM> of the support <NUM>) and a shunt resistor <NUM>. The shunt resistor <NUM> can be selected so as to render the LCR sufficiently accurate to measure impedances in the <NUM> to about <NUM>,<NUM> ohm range (e.g., <NUM> to about <NUM>,<NUM>, <NUM> to about <NUM>,<NUM>, <NUM> to about <NUM>,<NUM>, <NUM> to about <NUM>,<NUM>, <NUM> to about <NUM>,<NUM>, or <NUM> to about <NUM>,<NUM> ohm range). The electrokinetic device <NUM> functions in the circuit <NUM> as a measurement cell, with the base (e.g., a semi-conductor device) and cover (e.g., having an indium tin oxide (ITO) layer) of the electrokinetic device <NUM> functioning as electrodes. In certain specific embodiments, the output <NUM> of circuit <NUM> can come from the waveform generator <NUM> of a RED PITAYA™ device and the inputs <NUM>, <NUM> can originate from the electrokinetic device <NUM> and be received by the sensing module <NUM> of the RED PITAYA™ device. In certain specific embodiments, the shunt resistor <NUM> can be a <NUM> ohm resistor. In these embodiments, the electrical generation subsystem <NUM> may be switched between an "optical actuation mode" and an "LCR mode. " Moreover, when in LCR mode, the electrical generation subsystem <NUM> can be connected to a computer running a MATLAB script.

The system of the invention thus provides methods for determining the flow volume (Vflow) of an electrokinetic device <NUM>. For example, the electrokinetic device <NUM> is initially filled with a first fluid associated with a first impedance (e.g., DI, which is associated with an impedance of about <NUM> ohms). Then, a second fluid associated with a second impedance that is detectably different than the first impedance (e.g., PBS, which is associated with an impedance of about <NUM> ohms) is flowed into and through the electrokinetic device <NUM>. The second fluid can be flowed into the electrokinetic device <NUM>, for example, through a port capable of functioning as either a fluid inlet port or a fluid outlet port. The system continuously measures the complex impedance of the electrokinetic device <NUM> as the second fluid is flowing into and through the electrokinetic device <NUM>. As discussed above, to measure the complex impedance of the electrokinetic device <NUM> at a particular time point, the system applies a voltage potential to the electrokinetic device <NUM> and, concomitantly, receives signals from the electrokinetic device <NUM> that are used to calculate the complex impedance. The voltage potential applied to the electrokinetic device can have a frequency of about <NUM> to about <NUM> (e.g., about <NUM> to about <NUM>, about <NUM> to about <NUM>, about <NUM> to about <NUM>, about <NUM> to about <NUM>, about <NUM> to about <NUM>, or about <NUM>). The specific frequency can be selected based on properties of the electrokinetic device <NUM> and the first and second fluids so as to optimize accuracy of the impedance measurement, minimize measurement time, and reduce inductive effects. The second fluid is flowed into and through the electrokinetic device <NUM> until the measured complex impedance changes from the first impedance associated with the first fluid to the second impedance associated with the second fluid. The minimum amount of second fluid required to completely switch the complex impedance of the electrokinetic device <NUM> from the first impedance to the second impedance is a measure of the flow volume (Vflow) of the electrokinetic device. Starting from the point when the system begins to pump the second fluid to the electrokinetic device <NUM>, the volume of the second fluid required to switch the complex impedance of the electrokinetic device <NUM> from the first impedance to the second impedance can include (<NUM>) the flow volume (Vflow) of the electrokinetic device <NUM>, (<NUM>) the volume of the fluid outlet port of the electrokinetic device, and (<NUM>) the flow volume of the tubing carrying the second fluid from a pump to the electrokinetic device <NUM>. Because the flow of the second fluid through the tubing and fluid outlet port does not change the complex impedance of the electrokinetic device <NUM>, the flow volume of the tubing and inlet port can be readily distinguished from the flow volume of the electrokinetic device <NUM>.

Using the calculated flow volume of an electrokinetic device <NUM>, the system further provides methods for reliably exporting one or more micro-objects from the electrokinetic device <NUM> in a discrete volume of fluid. Having determined the flow volume (Vflow) of the electrokinetic device <NUM>, the minimal export volume (Vex) needed to export a micro-object (e.g., a biological cell) positioned within the flow path can be approximated by calculating the portion of the flow path that separates the micro-object from the fluid outlet port of the electrokinetic device <NUM>. For example, a total length (Ltot) of the flow path can be determined by tracing the flow path of the electrokinetic device <NUM> from the fluid inlet port to the fluid outlet port. The export length (Lex) of the flow path can be determined by tracing the flow path of the electrokinetic device <NUM> from the location of the micro-object in the flow path to the fluid output port. The minimal amount of fluid (Vex) needed to export the micro-object from the electrokinetic device <NUM> can thus be calculated as: Vex = (Lex/Ltot) * Vflow. Alternatively, the total volume of the flow path (Vflow-tot) can be estimated from the predicted geometry of the flow path (e.g., using CAD drawings); and the total volume of the export flow path (Vex-tot) can likewise be calculated from the predicted geometry of the flow path. In such an embodiment, minimal amount of fluid (Vex) need to export the micro-object from the electrokinetic device <NUM> can be calculated as: Vex = (Vex-tot/Vflow-tot) * Vflow. Regardless of the approach to calculating Vex, the micro-object can be exported from the electrokinetic device <NUM> by flowing a volume of fluid through the fluid outlet port of the electrokinetic device <NUM> that is at least as large as Vex. To ensure reliable export, the micro-object can be exported from the electrokinetic device <NUM> by flowing a volume of fluid (Vex-rel) that is equal to C * Vex, wherein C is a scaling factor that is equal to about <NUM> or greater (e.g., about <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or greater). In some methods, a leading portion of Vex (or Vex-rel) is discarded before a residual volume (Vres, equal to Vex (or Vex-rel) minus the leading portion) that contains the micro-object(s) is exported from the electrokinetic device <NUM>. For example, Vex (or Vex-rel) could equal <NUM>µL and a leading volume of <NUM>µL could be discarded, resulting in the micro-object(s) being exported in a final volume Vres of <NUM>µL. In this manner, the micro-object(s) can be exported in a small but discrete volume of fluid. Depending on how the method is performed, Vex, Vex-rel, or Vres can be about <NUM>µL, <NUM>µL, <NUM>µL, <NUM>µL, <NUM>µL, <NUM>µL, <NUM>µL, <NUM>µL, <NUM>µL, <NUM>µL, <NUM>µL, <NUM>µL, or less. Typically, the volume of fluid containing the micro-object(s) (i.e., Vex, Vex-rel, or Vres) is exported through export tubing having a finite internal volume before reaching a collection receptacle. Accordingly, the calculations used in the methods can be adjusted to account for the known or estimated volume of the export tubing. For example, the export tubing could have an internal volume of <NUM>µL. In such a case, a Vex (or Vex-rel) of <NUM>µL would be adjusted to <NUM>µL, and a discarded leading volume of <NUM>µL would be adjusted to <NUM>µL, thus resulting in a Vres of <NUM>µL remaining the same.

In certain embodiments, the support <NUM> includes one or more valves coupled to the support <NUM>, the one or more valves being configured to limit (e.g., stop) movement of fluid within an electrokinetic device <NUM> coupled to the support <NUM>. Suitable valves can substantially lack internal dead space (i.e., space within the valve that is accessible to fluid but experiences very little fluid flux when fluid is flowing through the valve). At least one of the one or more valves is a thermally controlled flow controller, such as a freeze valve. <FIG> and <FIG> depict a thermally controlled flow controller <NUM> for use with a support <NUM> according to the invention. The flow controller <NUM> includes a a temperature regulation device <NUM>, a thermally conductive interface <NUM>, and a flow segment (hidden) of a fluid line <NUM>. The temperature regulation device <NUM> can include one or more Peltier thermoelectric devices (e.g., a stack of two, three, four, five, or more Peltier devices). The thermally conductive interface <NUM> may be made from a material having high thermal conductivity that is resistant to thermal damage, such as a metal (e.g., copper). The thermally conductive interface <NUM> can wrap around the flow segment of the fluid line <NUM>. The thermally conductive interface <NUM> can be, for example, a sleeve or other object that completely surrounds the flow segment of the fluid line <NUM>, or it can have a grooved surface that accommodates the flow segment of the fluid line <NUM> within its groove. The fluid in the fluid line <NUM> may be a liquid that freezes solid at a temperature achievable by the flow controller <NUM>. The thermally conductive interface <NUM> is disposed adjacent the temperature regulation device <NUM>, preferably in contact with a thermally conductive surface thereof to increase the efficiency of the flow controller <NUM>.

In certain embodiments, the thermally controlled flow controller <NUM> can include a heat sink <NUM>, which may be made of one or more materials having a high thermal conductivity (and low thermal capacitance), such as aluminum. Alternatively, the flow controller <NUM> can be configured to rest on and/or be secured to a heat sink <NUM>. In addition, the flow controller <NUM> can include insulating material <NUM>, which may be configured to prevent moisture from interfering with the function of the flow controller <NUM>, which can happen when moisture condenses on the thermally conductive interface <NUM> and/or temperature regulation device <NUM>. The flow controller <NUM> can also include a cover <NUM> or other device (e.g., a clamp) configured to hold the thermally conductive interface <NUM> against the temperature regulation device <NUM> and, e.g., thereby increase the efficiency of the flow controller <NUM>.

<FIG> depicts a socket <NUM> and a pair of valves, each a thermally controlled flow controller <NUM>, according to another embodiment. The flow controllers <NUM> are disposed directly upstream and downstream of the socket <NUM>. As shown in <FIG>, each flow controller <NUM> includes a heat sink <NUM>, and an enclosure <NUM>. Each enclosure <NUM> contains a temperature regulation device <NUM>, a thermally conductive interface <NUM>, and a flow segment of a fluid line <NUM>. The fluid lines <NUM> can be seen exiting from the flow controllers <NUM> and entering the socket <NUM>. The enclosures <NUM> may be made from a material having a low thermal conductivity and/or a low gas permeability. The material can be, for example, PVC. The enclosures <NUM> may each have a volume of at least twice (e.g., <NUM> to <NUM> times, <NUM> to <NUM> times, <NUM> to <NUM> times, <NUM> to <NUM> times, or <NUM> to <NUM> times) the volume of the respective temperature regulation devices <NUM> contained therein. The enclosures can be configured to prevent moisture from interfering with the function of the flow controllers <NUM>, which can happen when moisture condenses on the respective temperature regulation devices <NUM> and/or thermally conductive interfaces <NUM>. <FIG> also depicts a secondary heat sink <NUM> upon which the flow controllers <NUM> are mounted. The secondary heat sink <NUM> is configured to absorb heat from the heat sinks <NUM> of the flow controllers <NUM>.

<FIG> depicts the heat sink <NUM> and enclosure <NUM> of a thermally controlled flow controller <NUM> like the ones depicted in <FIG>. The underside of the enclosure <NUM> is visible in <FIG>, showing grooves <NUM> configured to accommodate the fluid line <NUM> (not shown) and/or at least part of the thermally conductive interface <NUM>. The grooves <NUM> can be further configured to hold the thermally conductive interface <NUM> (not shown) against the temperature regulation device <NUM> (e.g., one or more (e.g., a stack of) Peltier thermoelectric devices; not shown).

<FIG> depicts the exterior of a thermally controlled flow controller <NUM> according to still another embodiment. As shown, the flow controller <NUM> includes a cover <NUM>, a bottom portion <NUM>, and a heat sink <NUM>. The cover <NUM> defines respective pluralities of indicator openings <NUM>, <NUM> configured to allow indicators (e.g., LEDs) to be observed from a position external to the cover <NUM>. The indicators can be configured to indicate whether the flow controller <NUM> is on or off and/or whether the flow segment of the fluid line <NUM> is in an open (i.e., not frozen) or closed (i.e., frozen) configuration. In addition, the cover <NUM> can define fastener openings <NUM> configured to admit fasteners (e.g., screws) for assembly of the flow controller <NUM>. The bottom portion <NUM> defines a plurality of fluid line openings <NUM> configured to admit fluid lines (not shown) into the interior of the bottom portion <NUM>.

<FIG> depict the top and the bottom, respectively, of the cover <NUM> depicted in <FIG>, shown without the bottom portion <NUM>. The indicator openings <NUM>, <NUM> and the fastener openings <NUM> are also depicted in <FIG> also depicts a cavity formed in the underside of the cover <NUM>, which is configured to hold a PCB (not shown) of the thermally controlled flow controller <NUM>. The PCB can include circuitry configured to control one or more temperature regulation devices <NUM> (not shown) and/or one or more indicators (not shown). The cover <NUM> can be made from a low thermal conductivity material, such as PVC.

<FIG> depicts the bottom portion <NUM> and the heat sink <NUM> of the thermally controlled flow controller <NUM> depicted in <FIG>, shown without the cover <NUM>. The bottom portion <NUM> includes a sleeve <NUM> and an enclosure <NUM> configured to hold the sleeve <NUM>. The bottom portion <NUM> also defines fastener openings <NUM> configured to admit fasteners (e.g., screws) for mounting the cover <NUM> and the bottom portion <NUM> on the heat sink <NUM>. In addition to holding the sleeve <NUM>, the enclosure <NUM> also defines a plurality of fluid line openings <NUM> (shown in <FIG>), which correspond to a plurality of fluid line openings <NUM> in the sleeve <NUM> (as shown in <FIG>). The fluid line openings <NUM> pass completely through the enclosure <NUM> in the horizontal plane of the enclosure <NUM>. <FIG> is a perspective, view of the enclosure <NUM> from below. The angle of the perspective view shows two corresponding sets of fluid line openings <NUM> and two cavities <NUM> formed in the underside of the enclosure <NUM>. The cavities <NUM> in the enclosure <NUM> are each configured to hold a temperature regulation devices <NUM> (e.g., each having one or more (e.g., a stack of two or more) Peltier thermoelectric devices; not shown) and wiring associated therewith (not shown).

<FIG> depicts the heat sink <NUM>, which defines two cavities <NUM>, each configured to hold a temperature regulation device <NUM> (e.g., having one or more (e.g., a stack of two or more) Peltier thermoelectric devices). The heat sink <NUM> is also configured to be coupled to a support <NUM>, which may function as a secondary heat sink.

<FIG> depict a sleeve <NUM> configured to hold two fluid lines <NUM> (e.g., an inlet and an outlet; not shown). The sleeve <NUM> may be configured to completely enclose the flow segments of the fluid lines <NUM>. Alternatively, the sleeve <NUM> can have grooves configured to accommodate the flow segments of the fluid lines <NUM>. Thus, the sleeve <NUM> is an embodiment of a thermally conductive interface <NUM>. Accordingly, the sleeve <NUM> facilitates maintaining the flow segments of the fluid lines <NUM> in proximity to the temperature regulation device <NUM> (not shown). The sleeve <NUM> may be made of a high thermal conductivity (and low thermal capacitance) material, such as copper. The side view in <FIG> shows the fluid line <NUM> openings <NUM> defined by the sleeve <NUM>. As shown, the fluid line openings <NUM> pass completely through the sleeve <NUM> in the horizontal plane of the sleeve <NUM>. The fluid line openings <NUM> are substantially aligned with corresponding fluid line openings <NUM> in the enclosure <NUM> (as shown in <FIG>), such that, when the sleeve <NUM> is disposed in the enclosure <NUM> (as shown in <FIG>), the fluid lines <NUM> can pass through both the enclosure <NUM> and the sleeve <NUM>, Further, when the sleeve <NUM> is disposed in the enclosure <NUM> (as shown in <FIG>), the sleeve <NUM> is placed into contact with the tops of both temperature regulation devices <NUM> (e.g., each which can include one or more (e.g., a stack of two or more) Peltier thermoelectric devices; not shown).

In certain embodiments, the thermally controlled flow controller <NUM> also includes a thermistor (not shown). The thermistor is configured to monitor the temperature of the sleeve and/or the temperature regulation device <NUM> (or a surface thereof). The monitored temperature can provide feedback to indicate the open or closed condition of the flow controller <NUM>.

In certain embodiments, the thermally controlled flow controller <NUM> also includes or is operatively coupled to a printed circuit board (PCB; not shown), as discussed above. The PCB can be configured to interface with the thermistor. The PCB may also be configured to regulate the current (e.g., DC) delivered to the temperature regulation devices <NUM>. Further, the PCB may be configured to step down the current delivered to the temperature regulation devices <NUM>.

The thermally controlled flow controllers <NUM> described above are robust and have substantially eliminated dead spaces (compare to other fluid valves) in which bacteria or other debris can accumulate and/or grow, Further, the flow controllers <NUM> reduce microbial contamination associated with other types of valves. Moreover, the flow controllers <NUM> limit movement of fluid within a microfluidic device (e.g., an electrokinetic microfluidic device <NUM>) connected thereto, which would otherwise result from flexing of fluid lines connected to the inlets and outlets of the microfluidic device. To optimize the system for minimizing fluid movement within microfluidic devices, the flow controller(s) <NUM> should be disposed as close to the inlet and outlets of the microfluidic devices as practical,.

In certain embodiments, the support <NUM> can also include or interface with O<NUM> and CO<NUM> sources configured to maintain culture conditions. In certain embodiments, the support <NUM> can also include or interface with a humidity monitor/regulator.

The support <NUM> can have dimensions of about <NUM> to <NUM> inches (or about <NUM> to <NUM>) x about <NUM> to <NUM> inches (or about <NUM> to <NUM>) x about <NUM> to <NUM> inches (or about <NUM> to <NUM>). Although it can be desirable to keep the dimensions of the support <NUM> substantially within these exemplary dimensions, depending upon the functionality incorporated into the support <NUM> the dimensions may be smaller or larger than the exemplary dimensions. Although the exemplary support <NUM> has been described as including specific components configured for particular functions, supports according to other embodiments may include different components that perform various combinations and sub-combinations of the described functions.

In certain embodiments, the light modulating subsystem <NUM> comprises one or more of a digital mirror device (DMD), a liquid crystal display or device (LCD), liquid crystal on silicon device (LCOS), and a ferroelectric liquid crystal on silicon device (FLCOS), and. The light modulating subsystem <NUM> can be, for example, a projector (e.g., a video projector or a digital projector). One example of a suitable light modulating subsystem is the MOSAIC™ system from ANDOR TECHNOLOGIES™. In other embodiments, the light modulating subsystem <NUM> may include microshutter array systems (MSA), which may provide improved contrast ratios. In still other embodiments, the light modulating subsystem <NUM> may include a scanning laser device. In certain embodiments, the light modulating subsystem <NUM> can be capable of emitting both structured and unstructured light.

In certain embodiments, the support <NUM> and the light modulating subsystem <NUM> are each individually configured to be mounted on a microscope, such as a standard research-grade light microscope or fluorescence microscope. For example, the support <NUM> can be configured to mount of the stage of a microscope. The light modulating subsystem <NUM> can be configured to mount on a port of a microscope.

Accordingly, in certain embodiments, the invention provides methods for converting a light microscope into a microscope configured for operating an electrokinetic device <NUM>. The methods can include the steps of mounting a system that includes a support <NUM> (e.g., as described herein) and a light modulating subsystem <NUM> (e.g., as described herein) on a suitable microscope. The support <NUM> can be mounted onto a stage of said light microscope, and the light modulating subsystem <NUM> can be mounted onto a port of said light microscope. In certain embodiments, the converted light microscope can be configured to operate an optically actuated electrokinetic device <NUM> (e.g., an electrokinetic device having an OET and/or OEW configuration).

In other embodiments, the supports <NUM> and the light modulating subsystems <NUM> described herein can be integral components of a light microscope. For example, a microscope having an integrated support <NUM> and an integrated light modulating subsystems <NUM> can be configured to operate an optically actuated electrokinetic device <NUM> (e.g., an electrokinetic device having an OET and/or OEW configuration).

In certain related embodiments, the invention provides a microscope configured for operating an electrokinetic device <NUM>. The microscope can include a support <NUM> configured to hold an electrokinetic device <NUM>, a light modulating subsystem <NUM> configured to receive light from a first light source and emit structured light, and an optical train. The optical train can be configured to (<NUM>) receive structured light from the light modulating subsystem <NUM> and focus the structured light on at least a first region in an electrokinetic device <NUM>, when the device <NUM> is being held by the support <NUM>, and (<NUM>) receive reflected and/or emitted light from the electrokinetic device <NUM> and focus at least a portion of such reflected and/or emitted light onto a detector <NUM>. The optical train can be further configured to receive unstructured light from a second light source <NUM> and focus the unstructured light on at least a second region of the electrokinetic device <NUM>, when the device <NUM> is held by the support <NUM>. In certain embodiments, the first and second regions of the electrokinetic device <NUM> can be overlapping regions. For example, the first region can be a subset of the second region.

In certain embodiments, microscopes of the invention can further include one or more detectors <NUM>. The detector <NUM> can include, but are not limited to, a charge-coupled device (CCD), complementary metal-oxide semiconductor (CMOS), scientific complementary metal-oxide semiconductor (SCMOS), a camera (e.g., a digital or film camera), or any combination thereof. If at least two detectors <NUM> are present, one detector <NUM> can be, for example, a fast-frame-rate camera while the other detector <NUM> can be a high sensitivity camera. The microscope can also include an eye piece configured for visualization by a user. Furthermore, the optical train can be configured to receive reflected and/or emitted light from the electrokinetic device <NUM> and focus at least a portion of the reflected and/or emitted light on the additional detector <NUM>. The optical train of the microscopes can also include different tube lenses for the different detectors <NUM>, such that the final magnification on each detector <NUM> can be different.

In certain embodiments, the light modulating subsystems <NUM> of the microscopes of the invention can include one or more of a digital mirror device (DMD), a liquid crystal display/device (LCD), a liquid crystal on silicon device (LCOS), a ferroelectric liquid crystal on silicon device (FLCOS), and scanning laser devices. Furthermore, the DMD, LCD, LCOS, FLCOS, and/or scanning laser devices can be part of a projector (e.g., a video projector or a digital projector). In other embodiments, the light modulating subsystem <NUM> may include microshutter array systems (MSA), which may provide improved contrast ratios. In certain embodiments, the microscopes of the invention can include an embedded or external controller (not shown) for controlling the light modulating subsystem <NUM>. Such a controller can be, for example, an external computer or other computational device,.

In certain embodiments, the systems <NUM>/microscopes of the invention are configured to use at least two light sources <NUM>, <NUM>. For example, a first light source <NUM> can be used to produce structured light <NUM>, which is then modulated by a light modulating subsystem <NUM> for form modulated structured light <NUM> for optically actuated electrokinesis and/or fluorescent excitation. A second light source <NUM> can be used to provide background illumination (e.g., using unstructured light <NUM>) for bright-field or dark filed imaging. One example of such a configuration is shown in <FIG>. The first light source <NUM> is shown supplying structured light <NUM> to a light modulating subsystem <NUM>, which provides modified structured light <NUM> to the optical train of the microscope. The second light source <NUM> is shown providing unstructured light <NUM> to the optical train via the beam splitter <NUM>. Modified structured light <NUM> from the light modulating subsystem <NUM> and unstructured light <NUM> from the second light source <NUM> travel through the optical train together to reach beam splitter <NUM>, where the light <NUM>, <NUM> is reflected down through the objective <NUM> (which may be a lens) to the sample plane <NUM>. Reflected aiid/or emitted light <NUM>, <NUM> from the sample plane <NUM> then travels back up through the objective <NUM>, through the beam splitter <NUM>, and to a dichroic filter <NUM>. Light <NUM>, <NUM> can be modulated, structured light <NUM> and unstructured light <NUM>, respectively reflected from the sample plane <NUM>. Alternatively, light <NUM>, <NUM> can originate at or below the sample plane <NUM>. Only a fraction of the light <NUM>, <NUM> reaching the dichroic filter <NUM> passes through the filter <NUM> and reaches the detector <NUM>. Depending on how the system is being used, beam splitter <NUM> can be replaced with a dichroic filter (e. g, for detecting fluorescent emissions originating at or below the sample plane <NUM>).

As depicted in <FIG>, the second light source <NUM> emits blue light. Blue light reflected from the sample plane <NUM> is able to pass through dichroic filter <NUM> and reach the detector <NUM>. In contrast, structured light coming from the light modulating subsystem <NUM> gets reflected from the sample plane <NUM>, but does not pass through the dichroic filter <NUM>. In this example, the dichroic filter <NUM> is filtering out visible light having a wavelength longer than <NUM>. Such filtering out of the light from the light modulating subsystem <NUM> would only be complete (as shown) if the light emitted from the light modulating subsystem <NUM> did not include any wavelengths shorter than <NUM>. In practice, if the light coming from the light modulating subsystem <NUM> includes wavelengths shorter than <NUM> (e.g., blue wavelengths), then some of the light from the light modulating subsystem <NUM> would pass through filter <NUM> to reach the detector <NUM>. In such a scenario, the filter <NUM> acts to change the balance between the amount of light that reaches the detector <NUM> from the first light source <NUM> and the second light source <NUM>. This can be beneficial if the first light source <NUM> is significantly stronger than the second light source <NUM>.

One alternative to the arrangement shown in <FIG>, which accomplishes the same goal of changing the balance between the amount of light that reaches the detector <NUM> from the first light source <NUM> and the second light source <NUM>, is to have the second light source <NUM> emit red light and the filter <NUM> filter out visible light having a wavelength shorter than <NUM>.

In certain embodiments, the microscopes (or systems) of the invention further comprise a first light source <NUM> and/or a second light source <NUM>.

In certain embodiments, the first light source <NUM> can emit a broad spectrum of wavelengths (e.g., "white" light). The first light source <NUM> can emit, for example, at least one wavelength suitable for excitation of a fluorophore. The first light source <NUM> can be sufficiently powerful such that structured light emitted by the light modulating subsystem <NUM> is capable of activating light actuated electrophoresis in an optically actuated electrokinetic device <NUM>. In certain embodiments, the first light source <NUM> can include a high intensity discharge arc lamp, such as those including metal halides, ceramic discharge, sodium, mercury, and/or xenon. In other embodiments, the first light source <NUM> can include one or more LEDs (e.g., an array of LEDs, such as a 2x2 array of <NUM> LEDs or a 3x3 array of <NUM> LEDs) The LED(s) can include a broad-spectrum "white" light LED (e,g. , the UHP-T-LED-White by PRIZMATIX), or various narrowband wavelength LEDs (e.g., emitting a wavelength of about <NUM>, <NUM>, or <NUM>). In still other embodiments, the first light source <NUM> can incorporate a laser configured to emit light at selectable wavelengths (e.g., for OET and/or fluorescence).

In certain embodiments, the second light source <NUM> is suitable for bright field illumination. Thus, the second light source <NUM> can include one or more LEDs (e.g., an array of LEDs, such as a <NUM>×<NUM> array of <NUM> LEDs or a <NUM>×<NUM> array of <NUM> LEDs). The LED(s) can be configured to emit white (i.e., wide spectrum) light, blue light, red light, etc. In some embodiments, the second light source <NUM> can emit light having a wavelength of <NUM> or shorter. For example, the second light source <NUM> can emit light having a wavelength of substantially <NUM>, substantially <NUM>, or substantially <NUM>. In other embodiments, the second light source <NUM> can emit light having a wavelength of <NUM> or longer. For example, the second light source <NUM> can emit light having a wavelength of substantially <NUM>. In still other embodiments, the second light source <NUM> can emit light having a wavelength of substantially <NUM>.

In certain embodiments, the optical trains of the microscopes of the invention include a dichroic filter <NUM> that filters out, at least partially, visible light having a wavelength longer than <NUM>. In other embodiments, the optical trains of the microscopes of the invention include a dichroic filter <NUM> that filters out, at least partially, visible light having a wavelength shorter than <NUM> (or shorter than <NUM>). More generally, the optical train can also include a dichroic filter <NUM> configured to reduce or substantially prevent structured light from a first light source <NUM> from reaching a detector <NUM>. Such a filter <NUM> can be located proximal to the detector <NUM> (along the optical train). Alternatively, the optical train can include one or more dichroic filters <NUM> that is/are configured to balance the amount of structure light (e.g., visible structured light) from the light modulating subsystem <NUM> and the amount of unstructured light (e.g., visible unstructured light) from the second light source <NUM> that reaches said detector <NUM>. Such balance can be used to ensure that the structured light does not overwhelm the unstructured light at the detector <NUM> (or in images obtained by the detector <NUM>).

In certain embodiments, the optical trains of the microscopes of the invention can include an objective <NUM> configured to focus structured and unstructured light on an electrokinetic device <NUM>, with the objective being selected from a 100x, 60x, 50x, 20x, 10x, 5x, 4x, or 2x objective. These magnification powers are listed for illustration and not intended to be limiting. The objection can have any magnification.

The microscopes of the invention can include any of the supports <NUM> described herein. Thus, for example, the support <NUM> can include an integrated electrical signal generation subsystem <NUM> configured to establish, at least intermittently, a biasing voltage between a pair of electrodes in said electrokinetic device <NUM> when said device <NUM> is held by said support <NUM>. Alternatively, or in addition, the support <NUM> can include a thermal control subsystem <NUM> configured to regulate the temperature of said electrokinetic device <NUM> when said device <NUM> is held by said support <NUM>.

Any system or microscope described herein can further include an electrokinetic device <NUM>. The electrokinetic device <NUM> can be a microfluidic device <NUM>, such as a microfluidic device <NUM> configured to support dielectrophoresis or a microfluidic device <NUM> configured to support electrowetting. The electrokinetic device <NUM> can be an optically actuated electrokinetic device (e.g., an electrokinetic device having an OET and/or OEW configuration).

<FIG> depicts a structured light path <NUM> in an optical train according to some embodiments of the invention. The structure light path <NUM> depicted in <FIG> begins at a DMD <NUM>, which includes a glass cover <NUM> (e.g., a <NUM> glass plate). The DMD <NUM> may be part of a light modulating subsystem like the light modulating subsystem <NUM> depicted in <FIG>. The DMD <NUM> modifies light from a light source (not shown) to form structured light <NUM>. The structured light <NUM> is then focused by a tube lens <NUM> toward an objective <NUM> (which may be a lens). The objective <NUM> in turn focuses the structured light <NUM> onto a cover <NUM> (e.g., a cover glass). The cover <NUM> may be a cover of an electrokinetic device <NUM>, such as an optically actuated electrokinetic device. In the latter embodiment, the structure light can actuate and/or operate the optically actuated electrokinetic device <NUM> as described below.

<FIG> depicts an imaging light path <NUM> in an optical train according to some embodiments of the invention. The imaging light path <NUM> depicted in <FIG> begins at a sample plane <NUM>, which may coincide with the cover <NUM> of an electrokinetic device <NUM>. The sample plane <NUM> may be similar to the sample plane <NUM> depicted in <FIG>. Therefore, the light <NUM> in the imaging light path <NUM> may be reflected from the sample plane <NUM>. Alternatively, the light <NUM> pay have passed through the sample plane <NUM>. From the sample plane <NUM>, the light <NUM> is focused by an objective lens <NUM> and an achromatic tube lens <NUM> toward a camera plane <NUM>. The camera plane <NUM> can coincide with a detector (not shown), like the detector <NUM> shown in <FIG>. In this manner, the imaging light path <NUM> can be used to visualize a sample or a portion thereof disposed at the sample plane <NUM> (e.g., contained within an electrokinetic device <NUM>).

<FIG> depicts a system <NUM> having an optical train similar to the one depicted in <FIG>. In the system <NUM> depicted in <FIG>, the second light source <NUM> and the beam splitter <NUM> are disposed in the main light path between the sample plane <NUM> and the detector <NUM>, instead of beside the main light path as in <FIG>. In such embodiments, the second light source is sized, shaped and configured such that it does not interfere with the reflected and/or emitted light <NUM>, <NUM> from the sample plane <NUM>. Further, the beam splitter <NUM> may only act as a filter to modify the unstructured light <NUM> from the second light source <NUM> without changing the direction of the unstructured light <NUM>. In other embodiments, system <NUM> may not include the beam splitter <NUM>.

In certain embodiments, the second light source <NUM> comprises a light pipe and/or one or more LEDs (e.g., an LED array, such as a 2x2 of 3x3 array of LEDs).

<FIG> depicts two LED arrays that may be used as light sources in the systems <NUM> described herein. A first LED array <NUM> includes a <NUM> X <NUM> array of four LEDs. A second LED array <NUM> includes a <NUM> X <NUM> array of nine LEDs. Square arrays produce higher light intensity per unit area compares to non-square arrays. The LEDs in the arrays can have the same color/wavelength (e.g., ultraviolet, <NUM>, <NUM> or <NUM>). Alternatively, various subsets of the LEDs in the arrays can have different colors/wavelengths. Further, LEDs can natively emit a narrowband wavelength (e.g., a <NUM> wavelength), but be coated with a phosphorescent material to emit white light upon excitation with the narrowband wavelength.

<FIG> depicts a light pipe (or optical integrator) <NUM>, which may be configured to receive and propagate light from a light source, such as one of the LED arrays <NUM>, <NUM> depicted in <FIG>. Light pipes <NUM>, also known as "non-imaging collection optics," are configured to propagate light from one end thereof (i.e., an input aperture) to the other end thereof (i.e., an output aperture), with the light emitted from the output aperture being of substantially uniform intensity (i.e., the flux of light through a first area of defined size at the plane of the output aperture is substantially the same as the flux of light through any other area at the plane of the output aperture having the same defined size). The body walls of the light pipe <NUM> can be constructed from transparent glass or a transparent plastic. Light pipes <NUM> are available, e.g., from EDMOND OPTICS.

<FIG> depicts a light source <NUM> including a plurality of <NUM> X <NUM> LED arrays <NUM> coupled to a surface <NUM>. The surface <NUM> may be an LED board. The light source <NUM> may be disposed within a system such that it is movable relative to an aperture configured to receive light emitted from the light source <NUM>. For example, the system can comprise a light pipe/optical integrator <NUM>, and an input aperture of the light pipe <NUM> can be configured to receive light emitted from one of the plurality of LED arrays <NUM> coupled to the surface <NUM>. Accordingly, different LED arrays <NUM> may be available as a light source (e.g., through the light pipe /optical integrator <NUM>) depending on the relative positions of the surface <NUM> of the light source <NUM> and the light pipe /optical integrator <NUM>.

<FIG> depicts a multi-input light pipe/optical integrator <NUM>. The multi-input light pipe <NUM> has a plurality (e.g., <NUM>) of input apertures, each associated with a light propagation pathway and respective light source <NUM>, <NUM>, <NUM>, and one fewer (e.g., <NUM>) dichroic filters <NUM>, <NUM>. Each dichroic filter <NUM>, <NUM> is configured to reflect light from a corresponding light source <NUM>, <NUM>. The multi-input light pipe <NUM> depicted in <FIG> has first, second and third light sources <NUM>, <NUM>, <NUM>, any of which may be an array of LEDs (e.g., a 2x2 or 3x3 array of LEDs). The first light source <NUM> may be an array of LEDs emitting light at around <NUM>. The second light source <NUM> may be an array of LEDs emitting light at around <NUM>. The third light source <NUM> may be an array of LEDs emitting light at around <NUM>. Therefore, the wavelength of light exiting from the multi-input light pipe <NUM> can be controlled by selectively activating the first, second and third light sources <NUM>, <NUM>, <NUM>. The multi-input light pipe <NUM> is configured such that light from any one of the light sources <NUM>, <NUM>, <NUM>, or any combination thereof, entering the corresponding input aperture(s) will be of substantially uniform intensity when it is emitted from the output aperture. The body walls of the multi-input light pipe <NUM> can be constructed from transparent glass or a transparent plastic.

In certain embodiments, the microscopes of the invention are configured to use a single light source (e.g., a white-light LED; not shown) which is received by the light modulating subsystem <NUM> and transmitted to the optical train. The single light source can be used to provide structured light for light actuated electrokinesis, fluorophore excitation, and bright field illumination. In such an arrangement, structured illumination can be used to compensate for optical vignetting or any other arbitrary non-uniformity in illumination. Optical vignetting is the gradual falloff of illumination <NUM> toward the edge of a field of view <NUM> (e.g., <FIG>). The light intensity of the single light source can be measured pixel by pixel and the information used to generate an inverted optical vignetting function <NUM> (e.g., <FIG>). The inverted optical vignetting function <NUM> can then be used to adjust the output of light from the light modulating subsystem, thereby producing a uniformly illuminated field <NUM> in the field of view <NUM> (e.g., <FIG>).

The invention further provides methods of using light to manipulate a micro-object in an optically actuated electrokinetic device <NUM>. The methods include placing an optically actuated electrokinetic device <NUM> onto the support <NUM> of any one of the systems or microscopes described herein, disposing a micro-object on or into the optically actuated electrokinetic device <NUM>, focusing structured light from a light modulating subsystem <NUM> onto a first region on a surface of the optically actuated electrokinetic device <NUM>, and moving the focused structured light to a second region on the surface of the optically actuated electrokinetic device <NUM>. Provided that the micro-object is located proximal to said first region, moving the focused light can induce the directed movement of the micro-object. The focused structured light can be used, for example, to create a light cage around the micro-object. Alternatively, the focused structured light can be used to contact, at least partially, a fluidic droplet that contains the micro-object.

In another embodiment of a method of using light to manipulate a micro-object in an optically actuated electrokinetic device <NUM>, a light pattern is spatially fixed, and the optically actuated electrokinetic device <NUM> is moved relative to the light pattern. For instance, the optically actuated electrokinetic device <NUM> can be moved using a motorized or mechanical microscope stage, which may be automatically controlled by a computer, manually controlled by a user, or semi-automatically controlled by a user with the aid of a computer. In another similar embodiment, the spatially fixed light pattern can form geometric patterns, such as a "cage" or a box, configured to move micro-objects (e.g., a biological cell or a droplet of solution optionally containing a micro-object of interest) on a steerable stage.

Claim 1:
A system for operating an optically actuated, OA, electrokinetic device (<NUM>), said system comprising:
a support (<NUM>) configured to hold and operatively couple with an OA electrokinetic device;
an electrical signal generation subsystem (<NUM>) configured to apply a biasing voltage across a pair of electrodes in said OA electrokinetic device when said OA electrokinetic device is held by, and operatively coupled with, said support;
a light modulating subsystem configured to emit structured light onto said OA electrokinetic device when said OA electrokinetic device is held by, and operatively coupled with, said support;
a thermal control subsystem configured to regulate a temperature of said OA electrokinetic device when said OA electrokinetic device is held by, and operatively coupled with, said support;
a first fluid line (<NUM>) having a distal end configured to be fluidically coupled to an inlet port of said OA electrokinetic device, and a second fluid line having a proximal end configured to be fluidically coupled to an outlet port of said OA electrokinetic device, respectively, when said OA electrokinetic device is held by, and operatively coupled with, said support; and
at least one thermally -controlled flow controller (<NUM>) operatively coupled with one or both of said first and second fluid lines;
wherein said support comprises a socket (<NUM>) configured to receive and interface with said OA electrokinetic device, and a microprocessor that controls said electrical signal generation subsystem and/or said thermal control system.