Patent Description:
Flow cytometers are useful for analyzing sample fluids having cells or particles and identifying characteristics of the cells or particles contained within a fluid. These cells or particles may be biological or physical samples that are collected for analysis and/or separation. The sample is mixed with a sheath fluid for transporting the cells or particles through the flow cytometer. The particles may comprise biological cells, calibration beads, physical sample particles, or other particles of interest.

<FIG> shows a schematic view of a typical flow cytometer. Referring to <FIG>, the fluid is typically passed through a flow chamber, such as a small nozzle, generating a narrow fluid stream. A light beam, such as a laser beam, illuminates the cells and particles and the like in the sample stream as they pass. Light detectors and color detectors <NUM> and <NUM> are positioned to detect scatter light and fluorescence light. This information is collected by a computer and then used by the flow cytometer to identify the particles or characteristics of the particles in the fluid. <FIG> shows a hydrodynamic focusing process of the flow chamber of the flow cytometer. When sheath fluid passes through the hydrodynamic focusing regions of the flow chamber, a single file of particles is produced in the flow cytometer system for analysis and characterization. The sheath fluid is often buffered saline or de-ionized (DI) water, but the sheath fluid may alternatively be any suitable fluid to hydrodynamically focus the sample fluid.

As flow cytometer systems become smaller and more portable, the sheath fluid containers and the waste fluid containers are becoming correspondingly smaller and more portable. As a result, portable flow cytometer systems may exhaust the supply of sheath fluid or overfill the waste container during the course of an experiment. While refilling or replacing the sheath fluid container and emptying the waste container takes a nominal amount of time and effort, the user must continuously suspend the experiment to ensure that the sheath fluid is not entirely depleted and that the waste container is not overfilled. Should the sheath container become empty, data sampled from or around the time when the sheath fluid ran out may be compromised. Accordingly, a user will typically have to provide a new sample material and run new experiments to ensure the accuracy of the data. Similarly, should the waste container overflow, the user will undoubtedly have to suspend the experiment in order to clean and sterilize the area. As the samples analyzed by flow cytometers vary from relatively benign to much less so, the overflow of the waste container can cause serious delays and perhaps hazardous conditions.

In view of the problems in the related art, there is a need for an improved flow cytometer system that is adapted to determine a volume of the sheath fluid or the waste fluid during operations and can expand the storage capacity of the sheath fluid or the waste fluid without causing any interruptions to the normal operations of a running flow cytometer system.

Aspects of the invention are set out in the appended independent claims.

Embodiments of the subject invention provide systems and methods for connecting an external fluidic system to an existing flow-cytometer-based system (for example, as a hot-swap option) to expand the storage capability of the flow-cytometer-based system by making only minimal changes to the flow-cytometer-based system.

In an aspect of the invention, a method for using a fluidic system is provided in claim <NUM>.

The fluidic system comprises a tubing connecting the fluidic system to a flow-cytometer-based system that has a first pump, a measurement device, a second pump, and a controller in operable communication with the second pump and the measurement device. The container contains a first fluid that is a sheath fluid flowing to the flow-cytometer-based system or a waste fluid flowing from the flow-cytometer-based system. The method comprises: operating, by the controller, the fluidic system to supply the first fluid from the container to the flow-cytometer-based system, when the first fluid is the sheath fluid, and to extract the first fluid from the flow-cytometer-based system and provide it to the container, when the first fluid is the waste fluid.

In another aspect of the invention, system for particle charachterization or separation is provided in claim <NUM>. The system for particle characterization or separation comprises a flow cytometer comprising a first pump; and a fluidic system in operable communication with the flow cytometer. The fluidic system comprises a container; a tubing connected to the flow cytometer; a second pump; a measurement device; and a controller in operable communication with the second pump and the measurement device, wherein the controller is configured to operate the fluidic system based on a condition of the flow cytometer.

In some embodiments, the measurement device measures a property of the sheath fluid or waste fluid in the container and transmits the measurement result to the controller. The controller determines whether the measurement result received is greater than or equal to a predetermined threshold value and adjusts an operation condition of the second pump to direct the fluid flow directions according to results of the determination.

In certain embodiments, the fluidic system performs its functionalities independent from any signal communications with the flow-cytometer-based system. In alternative embodiments, the fluidic system performs its functionalities based on signal communications with the flow-cytometer-based system.

Embodiments of the subject invention relate to advantageous external fluidic systems, methods of operating the same, and methods of using the same. An external fluidic system can be easily connected to an existing flow cytometer system to expand the fluid storage capability of the existing flow cytometer system by making only minimal changes to the existing flow cytometer system.

In some embodiments, an external fluidic system can be configured to, and/or used for, extracting waste fluid. Referring to <FIG>, an external waste fluidic system <NUM> for waste extraction includes an external waste pump <NUM> extracting the waste fluid from an (optional internal waste fluidic system <NUM> of the existing flow-cytometer-based system, and pumping the extracted waste fluid into a bulk container <NUM> connected to the external waste pump <NUM> via an optional valve <NUM> and can include a pressure sensor <NUM> coupled to the connecting tubing between the external waste pump <NUM> and the valve <NUM> to sense a pressure of the bulk container <NUM>; a platform/load cell <NUM> coupled to the bulk container <NUM> for measuring a primary parameter such as a volume of the fluid contained by the bulk container <NUM>; a float sensor <NUM> coupled to the bulk container <NUM> for measuring a secondary parameter such as a level of the fluid contained by the bulk container <NUM>; and a power/control unit <NUM> coupled to the external waste pump <NUM>, the pressure sensor <NUM>, the float sensor <NUM>, and the platform/load cell <NUM> to implement control functionalities of the external waste fluidic system <NUM>. The external waste fluidic system <NUM> may include a vent filter <NUM> connected to the bulk container <NUM> to filter the vent of the bulk container <NUM> and a power source (not shown) connected to the external waste fluidic system <NUM> to supply power to the external waste fluidic system <NUM>. The external waste fluidic system <NUM> includes connection tubing and optionally a coupler such as a dry break connector <NUM> to be connected to the existing flow-cytometer-based system.

The existing flow-cytometer-based system that the external waste fluidic system <NUM> is capable of connecting to may include an internal waste fluidic system <NUM>. The internal waste fluidic system <NUM>, if present, can include an internal waste evacuation pump <NUM> to extract the waste fluid from the internal waste bottle <NUM> that contains the waste fluid generated by the operations of the flow-cytometer-based system, and to pump the extracted waste fluid into an internal bulk waste tank <NUM>. An internal waste valve <NUM> (e.g., a waste valve that can control which internal waste tank the waste is directed to. such as the ½ valve in the Bio-Rad ZE5 system) and an internal waste three-way connector <NUM> are disposed between the internal waste evacuation pump <NUM> and the internal bulk waste tank <NUM>. The external waste fluidic system <NUM> may be connected to the internal waste fluidic system <NUM> through the internal waste three-way connector <NUM>.

The bulk container <NUM> is used to contain the waste fluid generated by the flow-cytometer-based system and works as an extra storage in additional to the internal bulk waste tank <NUM> of the internal waste fluidic system <NUM>, thereby enlarging the capacity of the flow-cytometer-based system for storage of the waste fluid when connecting the external waste fluidic system <NUM> to the flow-cytometer-based system. The bulk container <NUM> can be, for example, a vented tank with a volume of approximately <NUM>, and the bulk container <NUM> may alternatively be any suitable container of any capacity.

In addition, the external waste fluidic system <NUM> may be used to extract fluids other than the waste fluid. For example, after the analysis operations of the flow-cytometer-based system are complete, the external waste pump <NUM> may be used to extract a bleaching agent from a bleach container of the internal waste fluidic system <NUM> into the bulk container <NUM>. As another example, after the analysis operations of the flow-cytometer-based system are complete, the external waste pump <NUM> may extract a cleaning agent (such as a detergent or an antimicrobial) from a cleaning agent container of the flow-cytometer-based system into the bulk container <NUM>.

The external waste pump <NUM> can be a peristaltic pump or alternatively any other suitable type of pump. The external waste pump <NUM> can have a known flow rate to pump speed ratio such that a control of speeds of the external waste pump <NUM> corresponds to a control of the flow rate of the waste fluid.

Referring again to <FIG>, the valve <NUM> connects the external waste pump <NUM> at one end and the bulk container <NUM> at the other end and functions to facilitate the control of the waste fluid flow. The optional valve <NUM> can be a check-valve, such as a spring loaded check valve, but may alternatively be any suitable valve such as a by-pass valve, a restrictive valve, and/or a shutoff valve.

The platform/load cell <NUM> is a measurement device to measure a primary parameter of the waste fluid contained by the bulk container <NUM>. Referring to <FIG>, the platform/load cell <NUM> is preferably arranged such that it does not directly contact the waste fluid in the bulk container <NUM>. In an embodiment, the platform/load cell <NUM> includes one or more capacitive sensors disposed on or near the bulk container <NUM>. The capacitive sensors can sense: (<NUM>) the discrete presence or absence of the bulk container <NUM>; (<NUM>) the discrete presence or absence of the waste fluid in the bulk container <NUM>; or (<NUM>) capacity of the waste fluid in the bulk container <NUM>. Alternatively, the platform/load cell <NUM> may include one or more sensors to measure the weight, optical properties, acoustic properties or the like of the waste fluid and then calculate the volume of the waste fluid in the bulk container <NUM> based on the measurements.

As illustrated by <FIG>, the float sensor <NUM> measures a secondary parameter. such as a level of the waste fluid contained by the bulk container <NUM>, and is coupled to the power/control unit <NUM>. If the platform/load cell <NUM> fails to function, the power/control unit <NUM> may determine that the bulk container <NUM> is full based a measurement of the level provided by the float sensor <NUM>, in order to stop overflow of the bulk container <NUM>. In other words, the float sensor <NUM> may operate as a backup sensor in addition to the main sensor of the platform/load cell <NUM> to inhibit or prevent the waste fluid, which may include biohazard (e.g., carboy), from overflowing from the bulk container <NUM>. The pressure sensor <NUM> shown in <FIG> measures the pressure of the bulk container <NUM> and provides the measurement to the power/control unit <NUM>, allowing the power/control unit <NUM> to detect whether the pressure of the bulk container <NUM> exceeds a predetermined threshold (e.g., reaches a high enough level that may lead to an explosion or other safety issues). If the pressure does exceed the predetermined threshold, operation of the external waste pump can be suspended or shut down.

The power/control unit <NUM> of the external waste fluidic system <NUM> can be coupled to the external waste pump <NUM>, the pressure sensor <NUM>, the float sensor <NUM>, and the platform/load cell <NUM>. In an embodiment, the power/control unit <NUM> sets or adjusts the pump speed of the external waste pump <NUM> so as to set or adjust the flow rate of the waste fluid from the flow-cytometer-based system into the external waste fluidic system <NUM>. Alternatively, the power/control unit <NUM> may set or adjust operation parameters of the external waste pump <NUM> other than the pump speed, for example, power, pressure, or pump head and the like, for setting or adjusting the flow rate of the waste fluid from the flow-cytometer-based system to the external waste fluidic system <NUM>.

The power/control unit <NUM> can include a proportional-integral-derivative (PID) controller, but may alternatively be a proportional-integral (PI) controller, a proportional-derivative (PD) controller, a proportional (P) controller, or any other suitable type of controller. The power/control unit <NUM> may include an input device, including a keyboard, a mouse, a touch panel user interface, or other type of suitable input device, for receiving an input. In addition, the power/control unit <NUM> may include a display device including a display screen, a printer, or other type of suitable display device, for displaying output signals of the power/control unit <NUM> for a user to view. Therefore, the user may send a command input such as a predetermined pump speed value to the power/control unit <NUM> through the input device. When receiving the command input from the user, the power/control unit <NUM> sets or adjusts the external waste pump <NUM> of the external waste fluidic system <NUM> to operate at the predetermined pump speed value requested by the user.

In another embodiment, the user may send a command input through the input device to the power/control unit <NUM> requesting that the power/control unit <NUM> automatically determines the optimal pump speed for the external waste pump <NUM> to operate, in order to achieve the goal of making the waste fluid of the flow-cytometer-based system to flow to the bulk container <NUM> of the external waste fluidic system <NUM> through the internal waste three-way connector <NUM>.

<FIG> is a flow diagram of an example process of configuring the external waste fluidic system <NUM> of <FIG> to extract the waste fluid from the flow-cytometer-based system to the external waste fluidic system <NUM>. Referring to <FIG>, at step S100, when the flow-cytometer-based system is operated in a normal condition analyzing samples. the power/control unit <NUM> starts up the external waste fluidic system <NUM> including the external waste pump <NUM>.

Next, at step S200, the power/control unit <NUM> sets the external waste pump <NUM> to run at a pump speed higher than the pump speed of the internal waste evacuation pump <NUM> of the internal waste fluidic system <NUM> in response to an input from the user or alternatively, automatically determines an optimal pump speed for the external waste pump <NUM> to run at.

Next, at step S300, the external waste pump <NUM> runs at the pump speed set at step S200. Because the pump speed of the external waste pump <NUM> is set to be higher than the pump speed of the internal waste evacuation pump <NUM>. a pressure difference is created between the external waste fluidic system <NUM> and the internal waste fluidic system <NUM>, causing the waste fluid of the flow-cytometer-based system to flow to the bulk container <NUM> of the external waste fluidic system <NUM>.

For example, the external waste pump <NUM> and internal waste evacuation pump <NUM> can run simultaneously. at pump speeds in a same pump speed range of <NUM> - <NUM>%. When the internal waste evacuation pump <NUM> runs at <NUM>% of the pump speed range during a normal operation condition of the flow-cytometer-based system and runs at <NUM>% of the pump speed range in certain special operation conditions, the power/control unit <NUM> may set or adjust the external waste pump <NUM> to be operated at a pump speed greater than <NUM>% of the pump speed range.

Because the internal waste evacuation pump <NUM> and the external waste pump <NUM> run in parallel and compete with each other, when the external waste pump <NUM> runs at a pump speed higher than the internal waste evacuation pump <NUM>, a net suction is generated and applied to the tubing leading to the internal bulk waste tank <NUM>, thereby drawing the waste fluid generated by the flow-cytometer-based system to flow to the bulk container <NUM> of the external waste fluidic system <NUM> through the internal waste three-way connector <NUM> of the internal waste fluidic system <NUM>.

Next, at step S400, the platform/load cell <NUM> having one or more sensors senses or measures the volume of the waste fluid in the bulk container <NUM>, the float sensor <NUM> may measure the level of the waste fluid, and the pressure sensor <NUM> may measure the pressure of the bulk container <NUM>. The measurement result or results of the volume, the level of waste fluid, and the pressure are transmitted to the power/control unit <NUM>. In some cases, only one measurement (e.g.. the volume by the platform/load cell <NUM>) may be taken and transmitted, if the measurement is outside a normal operating range. In some cases, only two measurements (e.g., the volume by the platform/load cell <NUM> and either one of the level of the waste fluid by the float sensor <NUM> or the pressure of the bulk container by the pressure sensor <NUM>) may be taken and transmitted, if the either measurement is outside a normal operating range.

Next, at step S500, when receiving the measurement results, the power/control unit <NUM> determines whether the volume of the waste fluid is greater than or equal to a predetermined threshold value. If it is determined that the volume measured is greater than or equal to the predetermined threshold value, to avoid an overflow at the bulk container <NUM>, at step S600, the power/control unit <NUM> suspends or shuts down the operation of the external waste pump <NUM>. As a result, there is no pump competing with the running internal waste evacuation pump <NUM>. Consequently, the net suction between the external waste fluidic system <NUM> and the internal waste fluidic system <NUM> causes the waste fluid of the flow-cytometer-based system to flow only to the internal bulk waste tank <NUM> of the internal waste fluidic system <NUM>, not to the external waste fluidic system <NUM>.

If, at step S500, it is determined that the volume measured is smaller than the predetermined threshold value, then at step S510, the power/control unit <NUM> determines whether the level of the waste fluid is greater than or equal to a predetermined threshold value of level or the pressure of the bulk container <NUM> is greater than or equal to a predetermined threshold value of pressure. If it is determined that the level measured is greater than or equal to the predetermined threshold value of level or the pressure measured is greater than or equal to the predetermined threshold value of pressure. to avoid an overflow at the bulk container <NUM> or occurrences of hazardous conditions in the bulk container <NUM>. at step S600, the power/control unit <NUM> suspends or shuts down the operation of the external waste pump <NUM>. In some cases, only one of these measurements may be taken; if the measurement exceeds the threshold value. operation may be ceased and it may not be necessary to take the other measurement at that time.

On the other hand, if, at the step S510, it is determined that both the level measured is smaller than the predetermined threshold value of level and the pressure measured is smaller than the predetermined threshold value of pressure, then at optional step S520, the difference between the volume measured and the predetermined threshold value of volume is calculated and the difference is compared with a predetermined delta value. At optional step S540, if it is determined that the difference is greater than or equal to the predetermined delta value, the power/control unit <NUM> decreases the pump speed of the external waste pump <NUM> to reduce the inflow of the waste fluid to the external waste fluidic system <NUM> and at the same time, issues an alarm signal to the user in anticipation for an overflow at the bulk container <NUM>. If at optional step S520. it is determined that the difference is smaller than the predetermined delta value, then at step <NUM>, the power/control unit <NUM> maintains the external waste pump <NUM> to run at the set pump speed until the measurement result is greater than or equal to a predetermined threshold value.

Alternatively, at the step S510, if it is determined that the level measured is smaller than the predetermined threshold value of level and the pressure measured is smaller than the predetermined threshold value of pressure, and if the optional steps S520 and S540 are not performed, the power/control unit <NUM> may, at step S560, maintain the external waste pump <NUM> to run at the set pump speed until the measurement result is greater than or equal to a predetermined threshold value. In an embodiment, the external waste fluidic system <NUM> operates independent of any signal/input from the flow-cytometer-based system. In other words, there is no deliberate signal communication between the external waste fluidic system <NUM> and the flow-cytometer-based system. Even though the systems are connected and in operable communication or operation via at least the tubing (or other connection means), there is no deliberate sending or receiving of signals between the systems (e.g.. electric/electronic signals. magnetic signals, optical signals, pressure signals, pneumatic signals, or strain signals). Therefore, the external waste fluidic system <NUM> carries out its functionalities free of any signal communication with the flow-cytometer-based system.

In another embodiment, the external waste fluidic system <NUM> may be operated with signal communications with the flow-cytometer-based system. In other words, the external waste fluidic system <NUM> carries out its functionalities in response to an input or request signal from the existing flow-cytometer-based system and by transmitting an output or feedback signal to the existing flow-cytometer-based system.

<FIG> is a schematic view of an external sheath fluidic system connected to an (optional) internal sheath fluidic system of a flow-cytometer-based system according to an embodiment of the subject invention. Referring to <FIG>, an external sheath fluidic system <NUM> for supplying sheath fluid includes an external sheath pump <NUM> supplying the sheath fluid to the (optional) internal sheath fluidic system <NUM> of the existing flow-cytometer-based system, and pumping the sheath fluid from a bulk container <NUM> connected to the external sheath pump <NUM> via an optional valve <NUM> and can include a pressure sensor <NUM> coupled to the connecting tubing between the external sheath pump <NUM> and the valve <NUM> to sense pressures of the external sheath pump <NUM>; a platform/load cell <NUM> coupled to the bulk container <NUM> for measuring parameters of the fluid contained by the bulk container <NUM>; and a power/control unit <NUM> coupled to the external sheath pump <NUM>, the pressure sensor <NUM>, and the platform/load cell <NUM> to implement control functionalities of the external sheath fluidic system <NUM>.

The external sheath fluidic system <NUM> includes a pressure regulator (not shown) or a power source (not shown) connected to the external sheath fluidic system <NUM> to supply power to the external sheath fluidic system <NUM>. The external sheath fluidic system <NUM> of <FIG> includes connection tubing optionally a coupler such as a dry break connector <NUM> to be connected to the existing flow-cytometer-based system.

The existing flow-cytometer-based system that the external sheath fluidic system <NUM> is capable of connecting to may include an internal sheath fluidic system <NUM>. The internal sheath fluidic system <NUM> is optional, though the internal bulk sheath tank <NUM> will generally be present in most cases. If present, the internal sheath fluidic system <NUM> includes an internal sheath pump <NUM> to supply the sheath fluid to the internal sheath bottle <NUM> from the internal bulk sheath tank <NUM>. An internal sheath valve <NUM> (e.g.. a sheath valve that can control which internal sheath tank the sheath is directed to, such as the ½ valve in the Bio-Rad ZES system), an internal sheath three-way connector <NUM>, and an external source valve <NUM> can be disposed between the internal sheath pump <NUM> and the internal bulk sheath tank <NUM>. The external sheath fluidic system <NUM> may be connected to the internal sheath fluidic system <NUM> through the internal sheath three-way connector <NUM> and the external source valve <NUM>.

When a level of the sheath fluid in the internal bulk sheath tank <NUM> is lower than a predetermined level (for example, less than half full), the external source valve <NUM> may be configured to allow the internal bulk sheath tank <NUM> to be filled from the bulk container <NUM>; and when the level of the sheath fluid in the internal bulk sheath tank <NUM> reaches a certain predetermined level (e.g., <NUM>% full), the external source valve <NUM> may be configured to close in order to stop filling the internal bulk sheath tank <NUM> from the bulk container <NUM>. The bulk container <NUM> may be used to contain the sheath fluid supplied to the flow-cytometer-based system and works as an extra storage in additional to the internal bulk sheath tank <NUM> of the internal sheath fluidic system <NUM>, thereby enlarging the capacity of the flow-cytometer-based system for storage of the sheath fluid when connecting the external sheath fluidic system <NUM> to the flow-cytometer-based system. The bulk container <NUM> can be, for example, a tank with a volume of approximately <NUM>, and the bulk container <NUM> may alternatively be any suitable container of any capacity.

In addition, the external sheath fluidic system <NUM> may be used to supply fluids other than the sheath fluid. For example, after the analysis operations of the flow-cytometer-based system is complete, the external sheath pump <NUM> may be used to supply a bleaching agent to a bleach container of the internal sheath fluidic system <NUM> from the bulk container <NUM>. As another example, after the analysis operations of the flow-cytometer-based system is complete, the external sheath pump <NUM> may supply a cleaning agent (such as a detergent or an antimicrobial) to a cleaning agent container of the flow-cytometer-based system from the bulk container <NUM>.

The external sheath pump <NUM> can be a peristaltic pump or alternatively any other suitable type of pump. The external sheath pump <NUM> can have a known flow rate to pump speed ratio such that a control of speeds of the external sheath pump <NUM> corresponds to a control of the flow rate of the sheath fluid.

Referring again to <FIG>, the valve <NUM> connects the external sheath pump <NUM> at one end and the bulk container <NUM> at the other end and functions to facilitate the control of the sheath fluid flow. The optional valve <NUM> can be a check-valve, such as a spring loaded check valve, but may alternatively be any suitable valve such as a by-pass valve, a restrictive valve, and/or a shutoff valve.

The platform/load cell <NUM> is a measurement device to measure parameters of the sheath fluid contained by the bulk container <NUM>. The platform/load cell <NUM> can be arranged such that is does not directly contact the sheath fluid in the bulk container <NUM>. In an embodiment, the platform/load cell <NUM> includes one or more capacitive sensors disposed on or near the bulk container <NUM>. The capacitive sensors can sense: (<NUM>) the discrete presence or absence of the bulk container <NUM>, (<NUM>) the discrete presence or absence of the sheath fluid in the bulk container <NUM>; or (<NUM>) capacity or a level of the sheath fluid in the bulk container <NUM>. Alternatively, the platform/load cell <NUM> may include one or more sensors to measure the weight, optical properties, acoustic properties or the like of the sheath fluid and then calculate the volume or level of the sheath fluid in the bulk container <NUM> based on the measurement.

The power/control unit <NUM> of the external sheath fluidic system <NUM> can be coupled to the external sheath pump <NUM>, the pressure sensor <NUM>, and the platform/load cell <NUM>. In an embodiment, the power/control unit <NUM> sets or adjusts the pump speed of the external sheath pump <NUM> so as to set or adjust the flow rate of the sheath fluid supplied to the flow-cytometer-based system from the external sheath fluidic system <NUM>. Alternatively, the power/control unit <NUM> may set or adjust operation parameters of the external sheath pump <NUM> other than the pump speed, for example, power, pressure, or pump head and the like, for setting or adjusting the flow rate of the sheath fluid supplied to the flow-cytometer-based system from external waste fluidic system <NUM>.

The power/control unit <NUM> can include a proportional-integral-derivative (PID) controller, but may alternatively be a proportional-integral (PI) controller, a proportional-derivative (PD) controller, a proportional (P) controller, or any other suitable type of controller. The power/control unit <NUM> may include an input device, including a keyboard, a mouse, a touch panel user interface, or other type of suitable input device, for receiving an input. In addition, the power/control unit <NUM> may include a display device including a display screen, a printer, or other type of suitable display device, for displaying output signals of the power/control unit <NUM> for a user to view. Therefore, the user may send a command input such as a predetermined pump speed value to the power/control unit <NUM> through the input device. When receiving the command input from the user, the power/control unit <NUM> sets or adjusts the external sheath pump <NUM> of the external sheath fluidic system <NUM> to operate at predetermined pump speed value requested by the user.

In another embodiment, the user may send a command input through the input device to the power/control unit <NUM> requesting that the power/control unit <NUM> automatically determines the optimal pump speed for the external sheath pump <NUM> to operate at, in order to achieve the goal of supplying the sheath fluid to the flow-cytometer-based system from the bulk container <NUM> of the external sheath fluidic system <NUM> through the internal sheath three-way connector <NUM>.

When the flow-cytometer-based system is operated in a normal condition analyzing samples, the internal sheath pump <NUM> keeps running to supply the sheath fluid from the internal bulk sheath tank <NUM> to the internal sheath bottle <NUM>. When a level of the sheath fluid in the internal bulk sheath tank <NUM> drops below a first predetermined level (for example, <NUM>% full), the external source valve <NUM> is configured to open, causing the external sheath fluidic system <NUM> shown in <FIG> to supply the sheath fluid from the bulk container <NUM> to the flow-cytometer-based system.

<FIG> is a flow diagram of an example process of configuring the external sheath fluidic system <NUM> to supply the sheath fluid to the flow-cytometer-based system. Referring to <FIG>, at step S700, when the power/control unit <NUM> senses that the external source valve <NUM> is open causing the pressure of the external sheath fluidic system <NUM> to change, the power/control unit <NUM> starts up the external sheath pump <NUM>.

Next, at step S800, the power/control unit <NUM> sets the external sheath pump <NUM> to run at a pump speed to generate a pressure of the external sheath fluidic system <NUM> that is sufficiently higher than a pressure of the internal sheath fluidic system <NUM> in response to an input or, alternatively, automatically determines an optimal pump speed for the external sheath pump <NUM> to run at.

Next, at step S900, the external sheath pump <NUM> runs at the pump speed set at step S800. The sheath fluid contained in the bulk container <NUM> is pumped to the internal bulk sheath tank <NUM> due to the sufficient high pressure difference between the external sheath fluidic system <NUM> and the internal sheath fluidic system <NUM>.

Next, at step S1000, the platform/load cell <NUM> having one or more sensors senses or measures the volume of the sheath fluid in the bulk container <NUM> and the pressure sensor <NUM> senses or measures the pressure of the external sheath fluidic system <NUM>. The measurement results of the volume and the pressure are transmitted to the power/control unit <NUM>.

Next, at step S1100, when receiving the measurement results, the power/control unit <NUM> determines whether the volume measured is smaller than a predetermined threshold value of volume. If it is determined that the volume measured is smaller than the predetermined threshold value for the volume, to avoid pumping from an empty bulk container <NUM>, at step S1200, the power/control unit <NUM> suspends or shuts down the operation of the external sheath pump <NUM>. As a result, there is no external sheath fluid flowing to the internal bulk sheath tank <NUM> Consequently, the flow-cytometer-based system continues to operate with the internal sheath fluidic system <NUM> causing the sheath fluid to be supplied only from the internal bulk sheath tank <NUM> of the internal sheath fluidic system <NUM>, not from the external sheath fluidic system <NUM>. If, at step S1100, it is determined that the volume measured is greater than or equal to the predetermined threshold value for the volume, then, at step S1150, the power/control unit <NUM> determines whether the pressure measured is greater than a predetermined threshold value for the pressure.

In the internal sheath fluidic system <NUM>, when the level of sheath fluid in the internal bulk sheath tank <NUM> reaches a second predetermined level (for example, <NUM>% full) that is greater than the first predetermined level, the external source valve <NUM> is configured to close. At step S1150, when the power/control unit <NUM> senses that the external source valve <NUM> is closed causing the pressure of the external sheath fluidic system <NUM> to go up to a level greater than the predetermined threshold value for the pressure, to avoid occurrences of pump running dead with leakage conditions in the external sheath fluidic system <NUM>, at step S1160, the power/control unit <NUM> suspends the operation of the external sheath pump <NUM> and only turns the external sheath pump <NUM> back on when the pressure measured is determined to be smaller than or equal to the predetermined threshold value for the pressure. On the other hand, if, at step S1150, it is determined that the pressure measured is smaller than or equal to the predetermined threshold value for the pressure, then the power/control unit <NUM> maintains the external sheath pump <NUM> to run at the set pump speed.

Such processes of filling the internal bulk sheath tank <NUM> with the sheath fluid from the bulk container <NUM> by starting and suspending the external sheath pump <NUM> repeat until a volume of the sheath fluid in the bulk container <NUM> is smaller than the predetermined threshold value for the volume (for example, until the bulk container <NUM> becomes empty). In an embodiment, the external sheath fluidic system <NUM> operates independent of any signal/input from the flow-cytometer-based system. In other words. there is no deliberate signal communication between the external sheath fluidic system <NUM> and the flow-cytometer-based system. Even though the systems are connected and in operable communication or operation via at least the tubing (or other connection means), there is no deliberate sending or receiving of signals between the systems (e.g., electric/electronic signals, magnetic signals, optical signals, pressure signals, pneumatic signals, or strain signals). Therefore, the external sheath fluidic system <NUM> carries out its functionalities free of any signal communication with the flow-cytometer-based system.

In another embodiment, the external sheath fluidic system <NUM> may be operated with signal communications with the flow-cytometer-based system. In other words, the external sheath fluidic system <NUM> carries out its functionalities in response to an input or request signal from the existing flow-cytometer-based system and by transmitting an output or feedback signal to the existing flow-cytometer-based system.

In some embodiments, different color caps can be used on the various components to help easily distinguish different containers (e.g., bulk container, internal bulk sheath tank, etc.) from each other and/or different valves or pumps from each other.

<FIG> provides illustrations of a user interface of a control panel (for example, an electro-mechanical control switch) of certain embodiments of the subject invention. It should be understood that the user interface shown in <FIG> is merely for illustrative purposes and should not be construed as intending to limit how and in what manner the external fluidic system or the flow-cytometer-based system carries out its functionalities.

As shown in <FIG>, the user interface of the control panel includes a System On/Off button to switch the external waste pump or the external sheath pump on or off; a System Running LED indicating the status of the above mentioned pumps wherein when the System Running LED is on, it indicates that the pumps are on and running; and a System Stopped LED indicating the status of the pumps wherein when the System Stopped LED is on, it indicates that the pumps are stopped. In addition, the user interface of the control panel includes a Silence Alarm button, which when pressed and then immediately released, causes an alarm signaling a hazardous condition (for example, the bulk container is full of waste fluid) of the external fluidic system to be silenced. In addition, when the Silence Alarm button is pressed and held for an extended period of time (for example, <NUM> seconds), the volume of the alarm sound can be adjusted. For example, when the Silence Alarm button is pressed and held for more than <NUM> seconds, the volume of the alarm sound can increase until the maximum volume is reached. If the Silence Alarm button is pressed and held for more than <NUM> seconds after the maximum volume is reached, the sound of the alarm can be silenced or the volume can decrease gradually until it is silenced. Distinguishable color caps can be used for the buttons of the user interface of the control panel to distinguish different functionalities of these buttons.

The user interface of the control panel further includes a Full LED indicator (for example, it can be green for the external sheath fluidic system and turn red and flashing for the external waste fluidic system when the bulk container for containing waste fluid is full). An Empty LED is included (for example, it can be green for the external waste fluidic system and turn red and flashing for the external sheath fluidic system when the bulk container for containing the sheath fluid is empty. A group of Level LEDs are also included indicating different levels (for example, ¼ full, ½ full, or ¾ full) of the fluid contained in the bulk container.

Further, the user interface of the control panel can include one or more hidden buttons that are not labeled or otherwise marked and are intended to be exclusively accessible to authorized personnel for service use. One of the hidden buttons can be an empty calibration button for calibration of an empty bulk container at service time. For example, when the empty calibration button is pressed and held for more than <NUM> seconds, values of certain parameters of the empty bulk container will be stored in a storage device such as a flash memory of a controller board (for example, a microcontroller or an FPGA controller). The other hidden button can be a full calibration button for calibration of a full bulk container. For example, when the full calibration button is pressed and held for more than <NUM> seconds, values of certain parameters of the full bulk container can be stored in a storage device such as a flash memory of a controller board (for example, a microcontroller or an FPGA controller).

The methods and processes described herein can be embodied as code and/or data. The software code and data described herein can be stored on one or more machine-readable media (e.g., computer-readable media), which may include any device or medium that can store code and/or data for use by a computer system. When a computer system and/or processor reads and executes the code and/or data stored on a computer-readable medium, the computer system and/or processor performs the methods and processes embodied as data structures and code stored within the computer-readable storage medium.

It should be appreciated by those skilled in the art that computer-readable media include removable and non-removable structures/devices that can be used for storage of information, such as computer-readable instructions, data structures, program modules, and other data used by a computing system/environment. A computer-readable medium includes, but is not limited to, volatile memory such as random access memories (RAM, DRAM, SRAM); and non-volatile memory such as flash memory, various read-only-memories (ROM, PROM, EPROM, EEPROM), magnetic and ferromagnetic/ferroelectric memories (MRAM, FeRAM), and magnetic and optical storage devices (hard drives, magnetic tape, CDs, DVDs); network devices; or other media now known or later developed that are capable of storing computer-readable information/data. Computer-readable media should not be construed or interpreted to include any propagating signals. A computer-readable medium can be, for example, a compact disc (CD), digital video disc (DVD), flash memory device, volatile memory, or a hard disk drive (HDD), such as an external HDD or the HDD of a computing device, though embodiments are not limited thereto. A computing device can be, for example, a laptop computer, desktop computer, server, cell phone, or tablet, though embodiments are not limited thereto.

In many embodiments, the external fluidic system can include one or more sheath fluid containers, one or more waste fluid containers, or a combination of any number of waste fluid containers and sheath fluid containers.

In certain embodiments, the external fluidic system can include additional control functions including, but not limited to:.

The external fluidic system may further include a mass storage device capable of storing and accessing software instructions and/or data to carry out the above mentioned certain methods and processes. In an alternative embodiment, the above mentioned methods and processes can be carried out by hardware implementations including but are not limited to, application-specific integrated circuit (ASIC) chips, field programmable gate arrays (FPGAs), and other programmable logic devices now known or later developed.

When the external fluidic system as illustrated by the embodiments of subject invention is connected to an existing flow-cytometer-based system, the overall capacity of the waste storage or the sheath storage of the existing flow-cytometer-based system can be easily expanded beyond its designed maximum capacity. Moreover, the external fluidic system can be hot plugged into or hot unplugged from the existing flow-cytometer-based system that runs an analysis of samples. Because the external fluidic system may operate without receiving a deliberate signal from or transmitting a deliberate signal to the existing flow-cytometer-based system, none of the components, structures, connections, control procedures, software program/data of the existing flow-cytometer-based system needs to be altered or reconfigured. Thus, the external fluidic system can be connected to a running flow-cytometer-based system as a hot swap connection option without interruptions to the operations of the flow-cytometer-based system. Further, because the external fluidic system is a self-contained system capable of being connected to an existing flow-cytometer-based system, it requires minimal efforts for maintainance and service, making it very suitable for commercial applications.

Claim 1:
A method for using a fluidic system (<NUM>, <NUM>), the fluidic system (<NUM>, <NUM>) comprising a container (<NUM>, <NUM>), a tubing connecting the fluidic system (<NUM>, <NUM>) to a flow-cytometer-based system that has a first pump (<NUM>, <NUM>), a measurement device (<NUM>, <NUM>), a second pump (<NUM>, <NUM>), and a controller (<NUM>, <NUM>) in operable communication with the second pump and the measurement device (<NUM>, <NUM>),
wherein the container (<NUM>, <NUM>) contains a first fluid that is a sheath fluid flowing to the flow-cytometer-based system or a waste fluid flowing from the flow-cytometer-based system, and
wherein the method comprises:
operating, by the controller (<NUM>, <NUM>), the fluidic system (<NUM>, <NUM>) to supply the first fluid from the container (<NUM>) to the flow-cytometer-based system, when the first fluid is the sheath fluid, or to extract the first fluid from the flow-cytometer-based system and provide it to the container (<NUM>), when the first fluid is the waste fluid, and
wherein the fluidic system (<NUM>, <NUM>) is characterized by further comprising a control panel with a user interface comprising a system on/off button that switches the second pump (<NUM>, <NUM>) on or off, a system running LED that indicates a status of the second pump (<NUM>, <NUM>) such that when the system running LED is on it indicates that the second pump (<NUM>, <NUM>) is on and running, a system stopped LED indicating the status of second pump (<NUM>, <NUM>) such that when the system stopped LED is on it indicates that the second pump (<NUM>, <NUM>) is stopped, a silence alarm button that causes an alarm signaling a hazardous condition of the fluidic system to be silenced when pressed and then immediately released by a user, a full LED indicator that indicates when the container (<NUM>, <NUM>) is full, an empty LED that indicates when the container (<NUM>, <NUM>) is empty, and a group of level LEDs that respectively indicate different levels of fluid contained in the container (<NUM>, <NUM>).