Patent Description:
Cartridge-based reagent delivery systems and methods with different actuation schemes and configurations are known. However, many are not versatile as they are suitable only for very specific applications and present different drawbacks.

<CIT> discloses a microfluidic cartridge for molecular diagnostic applications with membrane-based actuation for fluid transport. The cartridge requires small volumes of reagents to analyze samples. The cartridge however is not configured for receiving a slide containing samples or to allow low dead volume operation.

<CIT> discloses a microfluidic device adapted for facilitating cytometry analysis of particles flowing therethrough. The microfluidic device may comprise a chip comprising a plurality of chambers and be designed to sort a predetermined amount of cells into each chamber. The configuration of the device however does not prevent the occurrence of dead volumes.

<CIT> discloses a microfluidic device for the manipulation, amplification and analysis of fluid samples including, for example, blood platelet bacteria assays and antiglobulin testing. The microfluidic device is operably connected to a cartridge manifold for controlling pumping of fluids and for providing vacuum and pressurized air for cartridge valve actuation. However, the configuration of the device does not prevent the occurrence of cross-contamination which may be critical in applications requiring high specificity and sensitivity.

<CIT> discloses a microfluidic cartridge for placement onto a parallel pneumatic interface plate of a pneumatic instrument. The cartridge includes a three dimensional fluid channel, in which a fluid is to be transported, and a flexible membrane that is part of an outer surface of the cartridge. The flexible membrane is pneumatically deflectable from a ground state perpendicular to the plane of the flexible membrane in two directions when the cartridge is placed onto the parallel pneumatic interface plate. The configuration of the cartridge has also the disadvantage of being prone to cross-contamination and dead volumes.

In <CIT> microfluidic system for PCR (polymerase chain reaction) analysis is disclosed in which liquid samples and reagents are both fed into the microfluidic cartridge to be mixed and then fed through an on board CMOS image sensor for PCR analysis.

<NPL>, describes a method and device for fluorescence in situ hybridization (FISH) on a tissue sample immobilized on a microscope slide, the slide being mounted against a microfluidic chip having a sealing ring that forms with the tissue slide a chamber.

It is an object of this invention to provide a microfluidic cartridge allowing sequential multiplex processing of a biological sample fixed on a support with a sequence of reagents that generates accurate and reliable results yet is economical to produce and to use.

It is a specific object of this invention to provide a microfluidic cartridge allowing sequential multiplex processing of a biological tissue sample immobilized on a support such as a microscope slide, with a sequence of reagents that generates accurate and reliable results yet is economical to produce and to use.

It is advantageous to provide a microfluidic cartridge that is compact.

It is advantageous to provide a microfluidic cartridge that reduces the risk of cross contamination and problems associated with dead volumes in microfluidic networks.

It is advantageous to provide a microfluidic cartridge that is versatile and can be used or adapted for different applications.

Another object of this invention is to provide a biological sample processing system comprising a microfluidic cartridge and a micro cartridge operating system for automated processing of a sample of interest fixed on a support.

It is advantageous to provide a biological sample processing system capable of analyzing automatically different type of samples fixed on a support across a wide range of applications.

Objects of the invention have been achieved by providing a microfluidic cartridge according to claim <NUM>.

Objects of the invention have been achieved by providing a biological sample processing system according to claim <NUM>.

Disclosed herein is a microfluidic cartridge comprising a sampling device having a sealing ring arranged to form a microfluidic chamber when a support containing a biological sample fixed thereon is brought into contact with the sealing ring, and a microfluidic network device configured to supply reagents to the microfluidic chamber. The sampling device comprises inlet and outlet distribution networks in fluid communication with the microfluidic chamber and a slide holder to guide and position said support containing a biological sample on the sampling device. The microfluidic network device comprises a plurality of reagent inlet channels fluidly connectable to reagent sources, at least one reagent outlet channel fluidly connected to the sampling device inlet distribution network, and a plurality of valves operable to selectively connect the inlet channels to the at least one outlet channel, wherein the sampling device and microfluidic network device are formed on a common microfluidic support as a single part. The support may for instance be in the form of a microscope slide for positioning under a microscope in the viewing field of a camera or other optical detection system for analysis of the sample reacted with the reagents.

In an embodiment, the microfluidic cartridge further comprises a reagent reservoir body (formed in the microfluidic support containing a plurality of wells configured to be filled with reagents, wherein each well is fluidly connected to a corresponding inlet channel.

In an embodiment, the sampling device comprises a first arrangement of reagents distribution comprising inlet and outlet distribution networks arranged on two opposite sides of the microfluidic chamber and configured to direct flow of reagent(s) inside the microfluidic chamber along a first direction, and a second arrangement of reagents distribution comprising inlet and outlet distribution networks arranged on two other opposite sides of the microfluidic chamber and configured to direct flow of reagent(s) inside the microfluidic chamber in a second direction transverse to the first direction.

In an embodiment, the microfluidic support comprises an integrally formed plastic molded microfluidic board in which the inlet channels, outlet channel, and sampling device inlet and outlet distribution channels are formed.

In an embodiment, at least one reagent outlet channel is a common single outlet channel connected to a plurality of said reagent inlet channels, said outlet channel comprising valve portions and intermediate portions therebetween, wherein the valve portions are adjacent to outlet end portions of the inlet channels and the intermediate portions are fluidly connected to each other in series, and wherein each of said plurality of valves interconnect an outlet end portion of each inlet channel to a corresponding valve portion of the common reagent outlet channel, wherein each valve is switchable between a valve closed position in which fluid communication between a corresponding inlet channel and the reagent common outlet channel is closed, and a valve open position in which fluid communication between said inlet channel and the reagent common outlet channel is open.

In an example, the common reagent outlet channel extends generally in a direction transverse to an outlet end portion of the inlet channels.

In an example, the reagent common outlet channel comprises a first and a second main part which are spaced apart and extend in a direction transverse to an outlet end portion of the inlet channels.

In an embodiment, the microfluidic network device further comprises an external reagent inlet section comprising several reagent inlet couplings for fluidly coupling one or more external reagent inlet channels to external reagent sources.

In an example, the external reagent inlet section is adjacent to a valve section comprising the plurality of valves.

In an example, the valve section is positioned between the external reagent inlet section and the onboard reagent reservoir body.

In an embodiment, the sampling device is positioned adjacent a first end of the microfluidic support.

In an example, the onboard reagent reservoir body is positioned adjacent a second end of the microfluidic support opposite the first end.

In an embodiment, the microfluidic network device further comprises a cartridge outlet, a chamber outlet channel connected to the outlet distribution network of the sampling device, and at least two valves configured to fluidly interconnect respectively the chamber outlet channel or the reagent common outlet channel to the cartridge outlet in order to discharge the reagent residues coming from the microfluidic chamber of the sampling device during sample processing steps or to discharge washing solutions circulating through the reagent common outlet channel during a washing step.

In an embodiment, the microfluidic network device may be at least partly embedded inside the microfluidic board on a first side thereof, while the sealing ring of the sampling device and the onboard reservoir body are mounted on a second side of said microfluidic board opposite the first side.

In an embodiment, a valve section comprises the plurality of valves, the valve section comprising a deflectable membrane layer disposed on the microfluidic board.

Also disclosed herein, is a microbiological sample processing system comprising a microfluidic cartridge as set forth in any of the above embodiments, and a microfluidic cartridge operating system comprising a cartridge receptacle receiving the microfluidic cartridge, a valve interfacing assembly and a reservoir body interfacing assembly, wherein the valve interfacing assembly is operable to selectively actuate each valve to create a fluid communication between a corresponding inlet channel and the reagent outlet channel.

In an embodiment, the reservoir body interfacing assembly is operable to induce flow of a reagent from one or more wells into the microfluidic chamber of the sampling device.

In an embodiment, the reservoir body interfacing assembly comprises a delivery manifold head displaceable relative to the cartridge receptacle from a non-operating configuration to an operating configuration, in which the bottom face of the manifold head lies against the top face of the reservoir body, wherein the manifold head comprises a plurality of actuation lines disposed to be aligned with the plurality of wells.

In an embodiment, the valve interfacing assembly and the body reservoir interfacing assembly are in fluid communication with an external pressure source.

In an embodiment, the valve interfacing assembly may comprise a pressure delivery manifold head displaceable relative to the cartridge receptacle from a non-operating configuration to an operating configuration in which the bottom face of the manifold head lies against the valve section or multiple valve sections of the microfluidic network device, wherein the manifold head comprises a plurality of actuation chambers and corresponding actuation lines in fluid communication with each actuation chamber, the plurality of actuation chambers being disposed such that each chamber encloses the valve inlet and outlet orifices of the corresponding valve, wherein the pressure delivery manifold head is operable to selectively create a negative pressure inside one or more actuation chambers.

In an example, a sealing gasket may be arranged against the bottom face of said pressure delivery manifold head, configured to surround each outlet of the actuation lines to ensure that the manifold head of the second fluidic interfacing assembly is sealingly fitted against the top face of reservoir body when the processing system is in an operating configuration.

In an embodiment, the microfluidic network device may further comprise an external reagent inlet section comprising several reagent inlet couplings for coupling one or more inlet channels to external reagent sources, and wherein the microfluidic cartridge operating system further comprises an external reagent interfacing assembly comprises a reagent delivery manifold head operably connected to external sources of reagents, said reagent delivery manifold head comprising a plurality of reagent delivery lines disposed to be sealingly fitted with the corresponding reagent inlet couplings.

The use of the term "reagent" in the present application is intended to cover a variety of liquids or gases that are used in the microfluidic cartridge for various applications. Reagents may for instance comprise antibodies, imaging probes, washing buffers, chemical reagents, water, saline solutions and other liquids used in the application concerned. Sample liquids are intended to mean liquids that contain samples on which testing is applied, such samples for instance containing biological tissues or other microbiological matter, pollutants, or other substances on which a test on the properties thereof is intended to be carried out by a sampling device downstream of the microfluidic network device.

Sample types fixed (immobilized) on a sample support for use with the microfluidic cartridge include those fixed by cross-linking agents such as whole tissue samples and surgical or needle biopsies of different tissue types including for example breast tissue, lung tissue, tonsils, lymph node tissue, prostate tissue, gut tissue, liver tissue or kidney tissue. The microfluidic cartridge may also be used with tumor samples such as biopsies from breast cancer, lung cancer, prostate cancer, ovarian cancer, colorectal cancer and melanoma or with sample of fluidic nature such as blood or cell smears samples or with samples of microbial nature such as bacteria. The microfluidic cartridge may further be used with samples that are fixed by cross-linking reagents cut into thin sections and subsequently applied to a support/slide.

Referring now to the figures, in particular <FIG>, a microfluidic cartridge <NUM>, according to a first aspect of the invention, comprises a reservoir body <NUM> containing a plurality of wells 29a filled with reagents or sample liquids for the applications for which the microfluidic cartridge is intended, a sampling device <NUM> known per se (for instance as described in <CIT>) comprising a sealing ring <NUM> arranged to form a microfluidic chamber <NUM> when a slide containing samples is brought into contact with the sealing ring <NUM>, and a microfluidic network device <NUM> connected downstream of the reservoir body <NUM> and upstream of the sampling device <NUM> to which reagents (antibodies, imaging buffers, washing solutions, etc.. ) are supplied. The microfluidic network device <NUM> also comprises reagent inlet coupling 16a for connection to external reagent sources such as washing buffers which are usually used in high volumes exceeding the volume capacity of the wells 29a of the reservoir body <NUM>.

The volume of each well of the reservoir body ranges preferably from <NUM>µl to <NUM>, for instance around <NUM>µl. Fluidic actuation of reagents may be achieved by pressurizing either each well separately or a plurality of wells simultaneously via one or more pressurized sources.

In an embodiment, the reagents supply may be provided on board the cartridge by the plurality of wells 29a of the reservoir body <NUM>.

In another embodiment, the reagents supply may be provided by external reagent sources connected via tubing to reagent inlet couplings of the microfluidic network device.

In another embodiment the reagents supply may comprise a combination of reagents on board the cartridge in wells 29a of the reservoir body <NUM> and of external reagent sources connected via tubing to reagent inlet couplings of the microfluidic network device.

In an advantageous embodiment illustrated in <FIG>, the microfluidic network device <NUM> is at least partly embedded inside a microfluidic board <NUM> or disposed at least on a first side thereof. The sealing ring <NUM> of the sampling device <NUM> and the reservoir body <NUM> are mounted on a second side of the microfluidic board <NUM> opposite the first side. The sampling device <NUM> comprises a slide holder <NUM> having a clamping system <NUM> in order to maintain a slide containing a biological sample thereon sealingly fitted against the sealing ring <NUM> to form the bottom side of the microfluidic chamber <NUM>. The clamping system <NUM> may for instance comprise elastically biasable clips 36a supported by guiding rails <NUM> arranged adjacent opposite sides of the sealing ring <NUM> to facilitate the positional guiding and holding of a slide against the sealing ring <NUM>. The slide holder <NUM> is configured to hold a slide at a distance of about <NUM> from the microfluidic board <NUM>. The sample on the slide may also be dewaxed in an open-chamber configuration in order to remove residues which may clog the channels of the microfluidic network device <NUM> directly from the microfluidic chamber <NUM>.

The microfluidic network device <NUM> comprises a valve section <NUM> comprising a plurality of valves <NUM> (<FIG>) and an external reagent inlet section <NUM> comprising several reagent inlet couplings 16a for fluidly coupling one or more inlet channel <NUM> (<FIG> and <FIG>) to external reagent sources via tubing. The external reagent inlet section <NUM> is adjacent to the valve section <NUM> and both sections <NUM>, <NUM> are arranged between the reservoir body <NUM> and the sampling device <NUM> as shown for example in <FIG>.

In an embodiment, the valve section <NUM> comprises a deflectable membrane layer 14a disposed on the microfluidic board <NUM>. The microfluidic board <NUM> and deflectable membrane layer 14a may have essentially the same shape, for instance a substantially rectangular shape, or any other shape that optimizes the layout of the microfluidic network device, sampling device and reagent well / reagent connection sections for the intended biological sampling application.

The microfluidic network device <NUM> comprises a plurality of inlet channels <NUM> fluidly connected to respective wells 29a of the reservoir body <NUM> of the cartridge <NUM>. Each inlet channel <NUM> comprises an inlet end <NUM> and an outlet end <NUM> interconnected fluidly by an intermediate channel section <NUM>.

In a preferred embodiment, the microfluidic network device <NUM>, as best illustrated in <FIG> and <FIG>, further comprises one reagent common outlet channel <NUM> that comprises a first and a second main part. Each main part comprises valve portions <NUM> and intermediate portion <NUM> therebetween. The valve portions <NUM> are positioned adjacent to the outlet ends <NUM> of the inlet channels <NUM> and the intermediate portion <NUM> are fluidly connected to each other in series. The outlet ends <NUM> of adjacent inlet channels <NUM> may be offset such that the plurality of outlet ends <NUM> are not formed along a linear line but along a zigzag or wave shaped line, or other oscillating line shapes. The first and second main parts of the reagent common outlet channel are thus proximate to the outlet end <NUM> of respective inlet channel <NUM> and both extend along a generally zigzag, wavy or oscillating path. The offset adjacent outlet ends <NUM> that form an oscillating arrangement when looking at the plurality of outlet ends <NUM> allows a more compact arrangement, namely a closer distance between adjacent inlet channels by providing more space at the outlet end <NUM> for positioning of a corresponding valve <NUM>. The first and second main parts of the reagent common outlet channel <NUM> are spaced apart and extend generally in a direction transverse to the inlet channels <NUM>, or at least the outlet end portion of the inlet channels. Valve portions <NUM> of the reagent common outlet channel <NUM> thus extend transversely to the outlet end portion <NUM> of the inlet channel in an essentially "T" shaped arrangement. The first main part of the reagent common outlet channel <NUM> is connectable to the inlet channels <NUM> fluidly connected to the wells 29a of the reservoir body <NUM> while the second main part of the reagent common outlet channel <NUM> is connectable to the inlet channels <NUM> fluidly connectable to external reagent sources.

Referring to <FIG>, the valve may comprise a valve inlet orifice <NUM> formed at the outlet end <NUM> of the inlet channel, and a valve outlet orifice <NUM> above, or forming a portion of the reagent common outlet channel <NUM> and separated from the valve inlet orifice <NUM> by a valve separating wall portion <NUM>. A deflectable member 25a extends over the valve inlet orifice <NUM>, valve separating wall portion <NUM> and valve outlet orifice <NUM> such that when the deflectable member 25a is pressed against the valve separating wall portion <NUM>, fluid communication between the valve inlet orifice <NUM> and valve outlet orifice <NUM> of the valve is prevented (i.e. the valve is in a closed position). It may be noted that the valve outlet orifice <NUM> of the valve may either be a small orifice extending to the outlet channel <NUM>, but preferably forms part of the reagent common outlet channel <NUM>. In the latter variant, when liquid flows through the reagent common outlet channel <NUM>, the valve outlet orifice <NUM> of the valve <NUM> does not present any dead volume, and liquid in the valve outlet orifice is carried away by liquid flowing in the reagent common outlet channel <NUM>.

In an embodiment, the deflectable member 25a may comprise an elastic membrane, for instance in the form or a sheet of elastically deformable material.

In a variant, the deflectable member 25a may comprise a spring mounted valve plate, plunger or ball (not shown), for example comprising a compression spring that pushes the plate, plunger or ball against the edges of the outlet and inlet orifices <NUM>, <NUM>.

It may be noted that the notion of valve inlet orifice <NUM> and valve outlet orifice <NUM> may comprise a single continuous orifice as illustrated in <FIG> or a plurality of orifices (not shown). In particular, the valve inlet orifice, in view of its larger surface area, may be provided with a plurality of smaller orifices in order to provide better support for the deflectable member against the orifices, or to control the ratio of projected surface areas between the inlet and outlet.

In an embodiment, an outermost inlet channel 18a (<FIG> and <FIG>) may be connected to a washing solution that ensures that during washing, between application of different reagents, the outlet channel <NUM> is fully washed from one end 22a to the other end 22b to avoid contamination with liquids of a subsequent treatment cycle. In such an embodiment, the outermost inlet channel 18a at one end of the microfluidic network device connects an end 22a of the reagent common outlet channel <NUM> and the other end 22b of the outlet channel is connected to an outlet <NUM> of the microfluidic network device that may either be a waste line, a purge line, or a line connected to the sampling device.

The microfluidic network device <NUM> may therefore optionally comprise an outlet connected to the sampling device <NUM> as well as one or more purge or waste lines for expulsing liquid without going through the sampling device <NUM> or other device downstream of the device outlet, or for initial priming of the device during elimination of bubbles within the microfluidic network device.

In advantageous embodiments, the intermediate channel sections joining the inlet end <NUM> to the outlet end <NUM> of the inlet channels <NUM>, may be provided with flow control portions <NUM>. Flow control portions <NUM> may for instance comprise resistive channels that may be formed for instance by a serpentine channel configuration that slow the flow of fluid through the inlet channels.

The sampling device may further comprise suction holes <NUM> (see <FIG>) for open-chamber operation positioned near the sample processing chamber. These allow the draining of reagents and liquids injected into the microfluidic chamber <NUM> when the slide is not positioned thereon or when the slide is positioned in a non-sealed relation over the microfluidic chamber <NUM>. The sampling device may further comprise suction holes 39a, 39b, 39c, 39d arranged at corners outside of the microfluidic chamber in fluid communication with first and second channels <NUM>, <NUM>' respectively for open-chamber operation. The first and second channels are connected to respective first and second outlets 38a, 38b that may be arranged in the valve section <NUM> and connectable to an outlet channel, in particular the common outlet channel.

In an embodiment, the microfluidic cartridge <NUM> as shown in <FIG>, the sampling device <NUM> includes a first arrangement of reagents distribution comprising inlet and outlet distribution networks 33a, 33b arranged on two opposite sides of the microfluidic chamber <NUM> and a second arrangement of reagents distribution comprising inlet and outlet distribution networks 33c, 33d arranged on two other opposite sides of the microfluidic chamber <NUM>. The first arrangement of reagents distribution is configured to direct flow of reagent(s) inside the microfluidic chamber <NUM> along a first direction, preferably in the longitudinal direction of the microfluidic chamber <NUM>, while the second arrangement of the reagents distribution is configured to direct flow of reagent(s) inside the microfluidic chamber <NUM> in a second direction transverse to the first direction Different reagents may therefore flow along the first and second direction which are preferably orthogonal to each other The width of the channels of the inlet distribution networks 33c of the second arrangement may be larger or smaller than the width of the channels of the outlet distribution networks 33d of the second arrangement. For instance, , the width of the channels of the outlet distribution networks 33d of the second arrangement, may be larger than the width of the channels of the inlet distribution networks 33c of the second arrangement to accommodate the flow of materials such as waxy residues from fixated samples.

According to this embodiment, the various channels (e.g. inlet channels, reagent common outlet channel) of the microfluidic network device <NUM> and the channels of inlet and outlet distribution networks of the sampling device <NUM> of the microfluidic cartridge are grooved within the microfluidic board <NUM>. The grooves may be produced in a surface of the microfluidic board <NUM> by additive (3D printing, material deposition techniques, molding, injection molding) or subtractive (machining) manufacturing techniques. For instance the microfluidic board may advantageously be an integrally formed plastic part in which the inlet channels, reagent common channel, and sampling device inlet and outlet distribution channels are formed by a molding die. The microfluidic cartridge may comprise a base layer plate or film covering the surface of the microfluidic board <NUM> over the grooved channels (e.g. inlet channels, reagent common outlet channel) of the microfluidic network device <NUM> in order to sealingly form the channels of the cartridge <NUM>. The base layer may be welded, bonded or otherwise fixed against the board. The channels may also be formed integrally within a monolithic board by an additive manufacturing process.

In an embodiment (not shown), four distribution networks can be arranged according to a configuration using flow-directing valves on the cartridge, where the sampling device comprises three inlet distribution networks used to introduce reagents to the microfluidic chamber and one outlet distribution network used for collecting fluids from the microfluidic chamber <NUM>.

Referring to <FIG>, a biological sample processing system, according to an aspect of the invention, comprises a microfluidic cartridge of the type that has been described above and a microfluidic cartridge operating system. The operating system comprises a cartridge receptacle <NUM> receiving the microfluidic cartridge <NUM>, a valve interfacing assembly <NUM> and a reservoir body interfacing assembly <NUM> which are in fluid communication with an external pressure source.

In an embodiment, the valve interfacing assembly comprises a pressure delivery manifold head <NUM> displaceable relative to the cartridge receptacle <NUM> from a non-operating configuration to an operating configuration in which the bottom face of the manifold head <NUM> lies against the valve section <NUM> of the microfluidic network device <NUM> (<FIG>). The manifold head <NUM> comprises a plurality of actuation chambers <NUM> and corresponding actuation lines <NUM> in fluid communication with each actuation chamber. The plurality of actuation chambers <NUM> is disposed such that each chamber encloses the valve inlet and outlet orifices <NUM>, <NUM> of the corresponding valve. The pressure delivery manifold head <NUM> is operable to selectively create a negative pressure inside one or more actuation chambers <NUM> in order to deflect the deflectable member 25a of one or more valves <NUM> to create a fluid communication between at least one inlet channel <NUM> and the reagent common outlet channel <NUM> as shown in <FIG>. In a variant, it is also possible that the deflectable member 25a has a positive elastic pressure against the outlet, inlet and valve separating wall portions and the valve opening is actuated by an under-pressure in the actuation chamber <NUM>.

In a variant, the microfluidic operating system may control the valves by other means, for instance by electromagnetic, piezoelectric, hydraulic means that act on the deflectable member, for instance to press on the deflectable member to close the valve, or to release or to lift up the deflectable member, to open the valve.

In an embodiment, the reservoir body interfacing assembly comprises a pressure delivery manifold head <NUM> (<FIG> and <FIG>) displaceable relative to the cartridge receptacle <NUM> from a non-operating configuration to an operating configuration, in which the bottom face of the manifold head lies against the top face of the reservoir body <NUM>. The manifold head <NUM> comprises a plurality of actuation lines <NUM> disposed to be aligned with the plurality of wells 29a to induce flow of a reagent from one or more wells 29a into the microfluidic chamber <NUM> of the sampling device <NUM>. A sealing gasket <NUM> is arranged against the bottom face of the manifold head <NUM> and is and configured to surround each outlet of the actuation lines <NUM> to ensure that the manifold head is sealingly fitted against the top face of the reservoir body <NUM> when the processing system is in an operating configuration. The actuation lines may provide a constant pressure, whereby the valves <NUM> are individually selectively operable to selectively control flow of reagent in a corresponding inlet channel <NUM>. In a variant, the actuation lines <NUM> may be individually selectively pressurized to selectively induce flow of reagent in a corresponding inlet channel <NUM>.

In an embodiment, the microfluidic cartridge operating system of the biological sample processing system further comprises an external reagent interfacing assembly comprising a reagent delivery manifold head <NUM> operably connected to external sources of reagents. As shown in <FIG>, the reagent delivery manifold head <NUM> comprises a plurality of reagent delivery lines <NUM> containing each a sealing, for instance in the form of an O-ring <NUM>, disposed around the outlet portion of the delivery lines. The sealing may also be provided in the form of a gasket, similar to the configuration of <FIG>, between the manifold head <NUM> and the microfluidic support <NUM>. The delivery lines <NUM> of the reagent manifold head <NUM> are therefore configured to be sealingly coupled to the corresponding reagent inlet couplings 16a of the external reagent inlet section <NUM> of the microfluidic cartridge <NUM>.

The microfluidic cartridge operating system also comprises a clamping actuator <NUM> configured to apply a clamping force against the sample support (e.g. a standard microscope slide) to form an airtight microfluidic chamber for sample processing.

Claim 1:
Microfluidic cartridge (<NUM>) comprising a sampling device (<NUM>) having a sealing ring (<NUM>) arranged to form a microfluidic chamber (<NUM>) when a support containing a biological sample fixed thereon is brought into contact with the sealing ring, and a microfluidic network device (<NUM>) configured to supply reagents to the microfluidic chamber,
the sampling device further comprising inlet and outlet distribution networks (33a, 33b) in fluid communication with the microfluidic chamber and a slide holder (<NUM>) to guide and position said support containing a biological sample on the sampling device,
the microfluidic network device comprising a plurality of reagent inlet channels (<NUM>) fluidly connectable to reagent sources, at least one reagent outlet channel (<NUM>) fluidly connected to the sampling device inlet distribution network (33a), and a plurality of valves (<NUM>) operable to selectively connect the inlet channels to the at least one outlet channel,
wherein the sampling device (<NUM>) and microfluidic network device (<NUM>) are formed on a common microfluidic support (<NUM>) as a single part.