Accessory for a plate of a microfluidic testing device with a microfluidic chip, microfluidic testing device plate, and microfluidic testing device

Abstract

The invention relates to an accessory for a plate (2) of a microscope microfluidic testing device comprising at least one sample holder (15) having at least one recess (20) for a microfluidic chip (8) and a series of fluid reservoir openings (21), and at least one collector (17) comprising at least one receptacle (30) open at the top that is arranged to be positioned beneath a first sub-series of openings (21) in the series of openings (21), the receptacle (30) being arranged so as to collect a fluid and enable light to pass through; a plate (2) and a microfluidic testing device.

Description

[0001] ACCESSORY FOR A MICROFLUIDIC CHIP MICROFLUIDIC EXPERIMENT DEVICE BOARD, A MICROFLUIDIC EXPERIMENT DEVICE BOARD, AND A MICROFLUIDIC EXPERIMENT DEVICE

[0002] The invention relates to an accessory for a microfluidic experiment device stage with a microfluidic chip, to a microfluidic experiment device stage and to a microfluidic experiment device.

[0003] Microfluidic experimentation involves conducting experiments involving the flow of fluids through micrometer-sized channels located in a microfluidic chip. The flow of fluids in these channels results in the frictional forces related to viscosity largely outweighing the inertial forces related to the flow. This results in a laminar flow in which the molecules composing the fluid progress while maintaining their relative positions to each other.

[0004] Microfluidic chips thus make it possible to manipulate and analyze tiny volumes of fluids. Multiple functions can be implemented on a single chip. It works by using the principles of fluid mechanics to manipulate and control the flow of fluids, typically in the order of microliters, or even nanoliters or picoliters.

[0005] Microfluidic chips are often made of materials such as glass, silicon, or polymers and are designed to accommodate precise and controlled fluid movements. Through a network of interconnected channels and chambers, fluids are directed and guided to perform various tasks, such as mixing, separation, reaction, and analysis.

[0006] Fluids can be introduced into a microfluidic chip via external sources, such as syringes or pumps, or by capillary action. Valves integrated into the microfluidic chip can regulate the flow of fluids, allowing precise control of the timing and sequencing of different operations. As previously mentioned, the small dimensions of the microfluidic chip's channels and chambers lead to advantageous properties, such as laminar flow (where different fluids flow in parallel layers without mixing). Specifically, laminar flow allows the fluid molecules to circulate while maintaining their relative positions to one another. These characteristics enable fast and efficient processes within the chip.

[0007] These miniature devices enable precise fluid control, enabling numerous applications in life sciences, biotechnology, chemistry, medical diagnostics, drug discovery, genetic analysis, environmental monitoring and point-of-care testing.

[0008] Via microfluidic droplet generators, microfluidic chips can be used to generate and manipulate water droplets in oil or oil droplets in water, both of which are immiscible, with high precision and control.

[0009] Microfluidic droplet generators consist of microchannels forming junctions or constrictions that allow precise control of the size and frequency of the formed droplets. The two immiscible fluids are introduced into the microfluidic chip through separate inlets and flow through a network of channels to the chip. The key element in the generation and manipulation of droplets in microfluidic chips is the presence of specialized structures called microfluidic droplet generators, the appropriate physicochemical property of the channel walls, and the appropriate flow and / or pressure regime. This technique is often referred to as droplet microfluidics, droplet-based microfluidics, or multiphase microfluidics.

[0010] Once formed, droplets can be transported and manipulated within the chip using a variety of techniques. External forces, such as electric fields, magnetic fields, or pneumatic pressures, can be applied to move, merge, split, or sort the droplets. Droplet manipulation can be achieved by changing flow rates, applying electrical potentials, or actuating valves within the chip.

[0011] When the two fluid streams meet at specific junctions within the chip, they break into droplets due to shear forces, surface tension, junction geometry, and flow dynamics. The emulsion droplets can be stabilized by surfactants initially dispersed in the aqueous and / or oil phase (also called the continuous phase). The surfactants form an interface around the droplets to prevent their coalescence. These stabilizing agents reduce the interfacial tension between the immiscible phases and promote the creation of interfaces.

[0012] Once the emulsion is formed, it can be further manipulated within the microfluidic chip. It is also possible to merge, split, or sort droplets based on their properties. This can be achieved by controlling liquid flow rates, pressures applied to the liquids, applying electric or magnetic fields, or actuating valves within the microfluidic chip.

[0013] Microfluidic technology has the advantage of using a small amount of sample. This also reduces reagent consumption.

[0014] The introduction of liquid into a microfluidic chip can be achieved by various methods, such as a flow rate control method, in which a syringe pump imposes a flow rate, or a pressure control method, in which pressure regulators impose pressure on the fluid reservoirs (outside or on the chip).

[0015] Pressure-driven flow is a method of using external pressure sources, such as pressure regulators. This applies positive or negative pressure to fluid reservoirs on the chip or connected to chip inlets via tubing. Using the applied pressure, fluid flows from the reservoir through the tubing into the microfluidic channels.

[0016] There is also a capillary action method: liquid is drawn into the microfluidic channels due to capillary forces.

[0017] In addition, the skilled person is also familiar with electrokinetic methods that require the application of an electric field to the liquid (e.g., electrophoresis and electroosmosis). The idea is to induce flow in the microfluidic channels. Electroosmosis involves the movement of the liquid due to the interaction between the electric field and the charged surfaces of the chip.

[0018] Droplet microfluidics systems therefore involve the generation and manipulation of discrete drops within microfluidic channels. This method produces well-defined drops, ranging in diameter from a micrometer to several hundred micrometers, at a rate of up to twenty thousand drops per second. Thanks to their large surface area to volume ratio, diffusion and mass and heat transfer phenomena are faster, allowing for shorter reaction times. Unlike continuous flow systems, droplet microfluidics systems allow the analysis of each independent droplet, thus generating microreactors that can be individually transported, mixed, and analyzed.

[0019] The ability to handle very small sample volumes is a major advantage of microfluidic analysis. This allows analyses to be performed from a small amount of material, reduces reagent consumption, achieves more rapidly detectable analyte concentrations, and provides faster results.

[0020] The micro-channels constituting the microfluidic chip are connected to each other in order to perform a desired function such as sorting, separation, mixing. This network of micro-channels enclosed in the chip is connected to the outside by inlets and outlets drilled through the chip. It is through these orifices that gases and liquids are injected and evacuated from the chip. Also, to be able to monitor, understand and analyze the phenomena, microfluidic chips are generally placed on a stage of a microfluidic experimental device.

[0021] By stage, we mean any platform of a fluidic experimentation device used to deposit the object to be visualized. The platform is preferably horizontal and often equipped with an XY table allowing its horizontal movement in order to adjust the position of the microfluidic channel to be observed and to the optical beam of the microfluidic experimentation device.

[0022] More generally, a microfluidic experimentation device comprises, but is not limited to, an inverted microscopy module, on either side of a stage, a fluorescence detection module with light excitation comprising one or more excitation sources (for example lasers or photodiodes) and photosensitive sensors (for example photomultiplier tubes), a pneumatic module typically comprising pumps and / or pressure regulators and / or solenoid valves, a fluidic module comprising connection tubes, reservoirs, an electronic module equipped with a power supply for components, signal acquisition and processing means, mechanical parts and supports.

[0023] Depending on the experiments carried out, the operator will need all the modules or only some of them, more or fewer tanks.

[0024] There are microfluidic experimentation devices where the modules are integrated, for example in a box, and typically the modules integrated in the box are the pneumatic modules. The box containing the pneumatic modules is often placed under the stage of the microfluidic experimentation device. In some microfluidic experimentation devices, the pneumatic module is a separate module to be placed on the table near the microfluidic experimentation device. When it comes to the fluidic module, the arrangements are generally varied, some reservoirs can be located in different places depending on what they must contain. Also before carrying out an experiment or an analysis using a microfluidic chip, the operator must then connect the different gas and liquid inlets and outlets with the circuit(s) of the microfluidic chip(s) using connecting tubes.A connecting tube is a flexible pipe generally made of PVC (polyvinyl chloride), FEP (fluorinated ethylene propylene), PTFE (polytetrafluoroethylene) or silicone, for example a tube or capillary.

[0025] When some modules are integrated into a box under the stage, connecting tubes are connected at one end to these modules while the opposite end ideally ends in the experimental area, that is to say above the stage to allow the operator to manipulate it. The connecting tubes thus pass either through the hole in the stage intended to let the light pass through, while other connecting tubes connect bottles, flasks or tubes on the table to the microfluidic chip, arranged above the stage. In other cases, the connecting tubes between a module integrated into a box under the stage and the chip placed in the experimental area bypass the stage which lengthens the connecting tubes.Sometimes the module integrated in a box under the board must be connected to a reservoir to perform an injection under the effect of pressure, and the liquid is then displaced under the effect of this pressure by a tube which connects the contents of the reservoir to the chip.

[0026] As one can easily understand, a microfluidic experiment usually results in a tangle of connecting tubes and an unpleasant clutter of the workspace.

[0027] Unfortunately, the operator cannot really move his bottles and flasks further apart because the distance would lengthen the connecting tubes, which would then create a dead volume, in which analytes of interest can be "lost", which affects precision, and presents a risk of bubbles.

[0028] In fact, the proximity of the reservoirs, and therefore the length of the connecting tubes connecting the reservoirs to the chip, depends on the mechanical system for carrying the reservoirs. The dead volume contained in these connecting tubes is all the more important as the reservoirs are far from the chip. In addition, the assembly is not very robust and is not integral with the chip because sometimes part of the experiment must be carried out under a sterile hood and it is then necessary to bring the chip as well as a series of tubes from the sterile hood to the microfluidic experimentation device. In other cases, part of the fluidic circuit, the chip, the reservoirs, etc. must be sterilized beforehand, which does not easily allow the creation of single-piece circuits and reservoirs.

[0029] Accessories such as those described in US2020 / 240898, US2017 / 014824, US2002 / 146841 were also available. Unfortunately, in these accessories, accessibility to the microfluidic chip and its movement for carrying out experiments or assembly under a hood or at a location remote from the microscope stage remain problematic.

[0030] Also disclosed in WO 2023 / 046783 is an accessory for a microfluidic experimentation device which at least partially solves the problem of tubing congestion.

[0031] Unfortunately, the proximity of connecting tubes carrying fluids, sometimes under pressure, with the electronic and optical elements of the microfluidic experimental device is such that there is a risk of damaging the electronic and optical elements following a leak of pressurized liquid.

[0032] The present invention aims to overcome these drawbacks by providing an accessory for the plate of a microfluidic experimentation device which makes it possible to simplify the handling and the production of the microfluidic / pneumatic circuit, to make the circuit robust while presenting increased security for the microfluidic experimentation device.

[0033] To this end, the present invention provides an Accessory for a plate of a microfluidic microscope experimentation device comprising: at least one sample holder arranged to be connected to said plate and to be housed at least partially in an orifice thereof, said at least one sample holder comprising a wall of a predetermined thickness, said at least one sample holder being detachable from said plate, said at least one sample holder having:

[0034] (i) at least one housing for at least one microfluidic chip, preferably formed in the thickness of said wall and having a bottom wall provided with a light passage orifice, said bottom wall of the housing being arranged to form a support wall for said at least one microfluidic chip,

[0035] (ii) a series of orifices, each orifice being arranged to receive a fluid reservoir at least one collector comprising at least one receptacle open on top, arranged to be disposed under a first sub-series of orifices of said series of orifices, said receptacle being arranged to collect a fluid and allow the passage of light.

[0036] As can be seen, according to the present invention, the accessory for a microfluidic experimentation device comprises a sample holder on which microfluidic reservoirs can be placed in the orifices of the series of orifices. The sample holder also comprises a housing for receiving a microfluidic chip, which brings the microfluidic reservoirs close to the microfluidic chip. This proximity makes it possible to reduce the length of the connecting tubes or tubing between the microfluidic reservoirs and the inlets / outlets of the microfluidic chip.

[0037] Thus, by being on the same sample holder, the connections between the reservoirs and the microfluidic chip can be made elsewhere than on the experimental device, such as, for example, on a laboratory bench or under a fume hood or fume cupboard.

[0038] According to the present invention, the reservoirs are generally pressurized by means of a compressed air inlet whose pressure is regulated by a pressure regulator. The reservoirs may be test tubes (e.g. 5 mL), centrifuge bottles (1.5 - 2 mL), Falcon-type tubes (15 or 50 mL), cryotubes, or other custom-made reservoirs. The reservoir is advantageously pressurized by means of a cover / mechanism connecting it in a sealed manner to an air inlet, and on the other hand to a liquid pipe leading to the chip. The accessory for an experimental device further comprises, according to the present invention, at least one collector which comprises a receptacle arranged to be placed under a first sub-series of orifices of the series of orifices.In this way, if a connection is not perfectly watertight and a connection accident occurs, the fluid is collected by the receptacle located below it while not obstructing the passage of light.

[0039] In this way, the analysis is not disturbed since the collector is arranged to allow the passage of light and the fluid that may have escaped is collected without spilling onto the electronic or optical elements inside the microfluidic experimentation device, which allows maintaining optimal visualization of the experiment occurring in the microfluidic chip and not spoiling the sample which may be very small, due to its rarity, for example.

[0040] Furthermore, after the microfluidic experiment, it is not necessary to disassemble the stage to remove any fluid spills; it is sufficient to clean the collector receptacle, which is accessible once the sample holder is removed, since it is open on top. In this way, the microfluidic experiment is not hindered, but post-experiment cleaning is not excessively burdensome. Not having to disassemble the stage and simply being able to access the collector receptacle also helps preserve the life and good quality of the microfluidic experiment device because in this type of device, any disassembly is a risk of decalibration or misadjustment.

[0041] According to the present invention, the collector is arranged to allow the passage of light, this means that it can for example have a light passage orifice and / or that it can extend under a part of the orifice of the plate, or under the entire plate, or even extend over a surface which is greater than the surface of the orifice of the plate.

[0042] In an advantageous embodiment of the present invention, the stage accessory further comprises a substantially annular interface, connecting said sample holder to said stage.

[0043] Said substantially annular interface has, within the meaning of the present invention, an outer contour described by the outer perimeter of the interface and an inner contour, which forms the perimeter of a hollowed-out portion. The length of the outer contour is greater than the length of the inner contour. The outer contour may describe a shape identical to or different from the shape of the inner contour.

[0044] Preferably, the outer contour describes a shape different from the shape described by the lower contour.

[0045] Preferably, according to an embodiment of the present invention, the substantially annular interface makes it possible to house the sample holder in the orifice of the stage, the annular interface being arranged to surround the sample holder with partial or non-partial overlap. The substantially annular interface can thus be arranged above the surface of the stage or be itself housed in the orifice of the stage, provided that the light passage orifice of the sample holder housed in the substantially annular interface is positioned above the optics of the microscope.

[0046] In yet another preferred embodiment of the present invention, said substantially annular interface comprises a peripheral lip arranged to rest on a shoulder of the plate, preferably on a shoulder forming the circumference of the orifice of the plate, without however being limited thereto.

[0047] More particularly, according to the present invention, said substantially annular interface is arranged to pivot around a vertical axis of rotation, centered at the center of a light beam of the microscope, typically oriented from bottom to top if the microscope is an inverted microscope and from top to bottom if the microscope is a non-inverted microscope.

[0048] Although it is also possible for the sample holder to pivot about a vertical rotation axis, centered at the center of the aforementioned light beam, within the annular interface, it is advantageous for the interface to be arranged to pivot about this rotation axis. Indeed, since the interface is annular, it surrounds the sample holder and can thus be more easily mobilized, either by a hand movement or by a control mechanism. In this latter configuration, the sample holder, once placed in the substantially annular interface, is secured to it under the effect of rotation.For this, the present invention provides that the sample holder is clipped into the substantially annular interface or that the shape of the sample holder, complementary to that of the internal section of the ring formed by the substantially annular interface, surrounding the sample holder is of a shape capable of blocking the rotation of the sample holder in the annular interface. Thus the sample holder will be for example square, rectangular, hexagonal, octagonal, oval, elliptical, partially circular with a non-circular part, such as for example rounded in shape with a non-round part. This non-round part may be curved or rectilinear.

[0049] Advantageously, the external contour of the substantially annular interface is ovoid in shape.

[0050] Equally advantageously, the external contour of the substantially annular interface is of circular shape trimmed on either side in a substantially rectilinear manner on each side of an axis of symmetry at the same distance. Thus the substantially annular interface is inscribed in a circle of diameter equal to the length of the substantially annular interface, but it has a width less than the diameter of the circle in which the interface is inscribed.

[0051] The orifice of the plate of the microfluidic experimentation device has an outline of the hollowed-out part which is of ovoid shape or of circular shape trimmed on either side in a substantially rectilinear manner on each side of an axis of symmetry at the same distance. Thus the hollowed-out part fits into a circle of diameter equal to the length of the hollowed-out part of the plate, but it has a width less than the diameter of the circle in which the hollowed-out part fits.

[0052] The length of the substantially annular interface is 0.1 to 5 mm less than that of the recessed portion of the orifice of the plate, preferably 0.2 to 3 mm less than that of the recessed portion of the orifice of the plate, more particularly 0.3, 0.5, 0.7, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2 mm less than that of the recessed portion of the orifice of the plate.

[0053] The width of the substantially annular interface is 0.1 to 5 mm less than that of the recessed portion of the orifice of the plate, preferably 0.2 to 3 mm less than that of the recessed portion of the orifice of the plate, more particularly 0.3, 0.3, 0.7, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2 mm less than that of the recessed portion of the orifice of the plate.

[0054] On either side of the axis of symmetry of the orifice of the plate, the orifice is widened so as to allow rotation of the substantially annular interface. Thus, the contour of the hollowed-out part of the orifice of the plate has an eccentric part on each side of the axis of symmetry. The distance between each of the most extreme points of the eccentric part and the center of rotation is slightly greater than the radius of the circle in which the orifice of the plate is inscribed.

[0055] The eccentric portion of the plate orifice is arranged to allow rotation of the substantially annular interface.

[0056] More particularly, in an advantageous form of the present invention, said substantially annular interface is arranged to pivot about said vertical axis of rotation when the peripheral lip of said substantially annular interface rests on said shoulder of the orifice of said plate.

[0057] In a preferred embodiment of the present invention, the turntable accessory comprises mutual control means connected to said substantially annular interface, said mutual control means being arranged to be engaged in control means arranged to be arranged on the turntable, and to impart a rotational movement of an amplitude preferably between +30° and -30°, preferably between +20° and -20°, more particularly between +15° and -15°, more particularly between +10° and -10°, even more particularly between +5° and -5° to said substantially annular interface.

[0058] The mutual control means and the control means are provided to engage together directly or via an intermediate part and cause the rotational movement of the substantially annular interface. The mutual control means are connected to the interface, for example they are present or arranged on the substantially annular interface or they are connected to it. Thus, the mutual control means can be chosen from a toothed wheel, a magnet, a side wall of the substantially annular interface, a smooth or notched part on the side wall of the interface .... They can be engaged by the intermediate part when it is present such as a belt, a pad, or any other means of transmitting movement. The control means can be chosen from a toothed wheel, a magnet, a wheel, a lever, a tensioner roller, an actuator.For example, the control means such as a toothed wheel which is arranged on the plate may be engaged in the mutual control means such as a toothed wheel which is present on the accessory. The rotation of the toothed wheel arranged on the plate causes the rotation of the toothed wheel present on the accessory and imparts a rotational movement to the substantially annular interface. Similarly, for example, the control means such as a magnet, linked to a wheel, arranged on the plate interacts with the mutual control means such as a magnet present on the accessory. The rotation of the wheel will move the linked magnet and the latter will, by reaction, exert a force on the magnet present on the accessory and cause the rotation of the substantially annular interface.For example, the intermediate part such as a belt engaged in a control means such as a tensioner roller disposed on the plate and in a mutual control means such as the turn of the substantially annular interface. The rotation of the tensioner roller will cause a rotation of the belt, which will cause a rotation of the substantially annular interface. For example, the control means such as a lever disposed on the plate and which has an intermediate part such as a pad in contact with the mutual control means such as a side wall of the substantially annular interface. When the lever moves, the pad causes the rotation of the substantially annular interface. For example, the control means such as an actuator disposed on the plate can transmit a force, a torque or a displacement to the mutual control means such as the substantially annular interface and cause the rotation thereof.

[0059] The rotational movement thus makes it possible to precisely align the channels of the microfluidic chip in relation to the microscope (in the field of view of the camera, and in relation to laser beams or active objects such as electrodes, magnets, etc.)

[0060] In one embodiment of the present invention, said collector is arranged to be fixed to said substantially annular interface or to said plate and preferably to said substantially annular interface, so as to facilitate its holding in place, but also its disassembly. When the collector is fixed to said substantially annular interface, when the latter is moved in rotation, it thus follows the movement of said interface and therefore of the sample holder which is housed in the substantially annular interface so as to be integral with the substantially annular interface when the interface is moved in a rotary manner.

[0061] Advantageously, according to the present invention, said collector has at least one end-to-end dimension L3 chosen from a width, a length or a diameter and said sample holder has at least one end-to-end dimension L2 chosen from a width, a length or a diameter with L3 > L2. In this way, the collector is larger than the sample holder, so as to be able to collect any fluid that may have accidentally flowed out and spilled onto the sample holder.

[0062] Preferably, L3 is also greater than a dimension selected from a width, a length or a diameter of the internal contour of the substantially annular interface, so that the collector can be easily fixed under the substantially annular interface. Preferably, L3 is also less than a dimension selected from a width, a length or a diameter of the orifice of the plate, so that the removal of the substantially annular interface to which the collector is fixed can be carried out by passing the collector fixed to the interface through the orifice of the plate.

[0063] In an alternative embodiment, the collector is fixed to the substantially annular interface by screws whose heads are located above the plate, for example if L3 is greater than a dimension chosen from a width, a length or a diameter of the orifice of the plate and cannot pass through the orifice of the plate, the removal of the substantially annular interface then requiring prior unscrewing to detach the collector from the substantially annular interface.

[0064] More particularly, in one embodiment, the collector has a surface S3 projected by a normal projection onto a horizontal plane and said sample holder has a surface S2 projected by a normal projection onto a horizontal plane, with S3>S2.

[0065] In a preferred embodiment, the housing for said microfluidic chip has two longitudinal walls which have an intersection with a peripheral of said sample holder so as to form a slide. Preferably, the housing for at least one microfluidic chip has an asymmetry, for example the width of the upper part of the slide is less than the width of the lower part of the slide. In this way, the cassette cannot be inserted in the wrong direction. This asymmetry also makes it possible to limit the degrees of freedom of the cassette within the slide and to secure the assembly.

[0066] In another embodiment according to the present invention, said accessory for a microfluidic experimentation device comprises a connector provided with pins arranged on said sample holder, said pins being arranged to be connected to electrodes for microfluidic chips, possibly through said microfluidic chip, said connector provided with pins being arranged to be pivotally mounted transversely relative to a median plane of said wall.

[0067] The connection between the microfluidic chip and the connector can be made by a connection plate which is clamped between the conductive plate of the electrode and the conductive part of the glass slide by means of a spring.

[0068] The connection between the electrodes of the microfluidic chip and the electrical connector of the board / board accessory can be made by sliding the cassette containing the microfluidic chip and whose electrodes are visible (upper surface of the chip) under the connection plate containing pins / spring interfaces / ... conductive.

[0069] In yet another embodiment according to the present invention, the stage accessory further comprises a cassette arranged to house said microfluidic chip and optionally an electrode or electrodes, said cassette comprising at least one light passage orifice as well as at least one fluid passage orifice arranged to be in fluid communication with a fluid inlet or outlet of a microfluidic chip.

[0070] Advantageously, the receptacle has a vertical dimension greater than the predetermined thickness (e). The receptacle has one or more walls that form a continuous receptacle wall so as to confine a fluid and thus collect it. This continuous wall extends beyond the predetermined thickness (e). The sample holder, the interface and the collector have, when assembled, a thickness (f) that is greater than or equal to said predetermined thickness (e). The continuous wall of the receptacle also advantageously extends beyond the thickness (f). Preferably, the receptacle has a bottom that is arranged to end near the optical parts of the microfluidic microscope experimentation device, under the stage thereof.

[0071] For example, the receptacle extends lower than the sample holder. This allows for an increased receptacle volume and allows for more fluid to be collected. In fluidic experiments, the microfluidic chip may be connected to fluid reservoirs, and these fluids flow in and out of the chip during the experiment. A potential leak may not be directly detected, and it is important to be able to collect a relatively large amount of fluid, typically more than the volume of fluid contained in the microfluidic chip, without the fluid overflowing from the receptacle.

[0072] Other embodiments of the microscope microfluidic experiment device stage accessory are indicated in the appended claims.

[0073] The present invention also relates to a microscope microfluidic experiment device stage comprising an accessory according to the present invention.

[0074] More particularly, the present invention relates to a stage for a microfluidic microscope experimentation device comprising a stage orifice arranged to allow the passage of light, preferably, the stage orifice is a hollowed-out part comprising a peripheral shoulder on which the accessory according to the present invention rests.

[0075] Advantageously, the fluidic experimentation device plate according to the invention comprises an accessory comprising at least one sample holder arranged to be connected to said plate and to be housed at least partially in an orifice thereof, said at least one sample holder comprising a wall of a predetermined thickness (e), said at least one sample holder being detachable from said plate, said at least one sample holder having:

[0076] (i) at least one housing for at least one microfluidic chip preferably, formed in the thickness (e) of said wall and having a bottom wall provided with a light passage orifice, said bottom wall of the housing being arranged to form a support wall for said at least one microfluidic chip,

[0077] (ii) a series of orifices, each orifice being arranged to receive a fluid reservoir, at least one collector comprising at least one receptacle open on top, arranged to be disposed under a first sub-series of orifices of said series of orifices, said receptacle being arranged to collect a fluid and allow the passage of light.

[0078] Preferably, the fluidic experimentation device plate according to the invention comprises an accessory further comprising a substantially annular interface connecting said sample holder to said plate.

[0079] Equally advantageously, the fluidic experimentation device plate according to the invention comprises an accessory in which said substantially annular interface comprises a peripheral lip arranged to rest on a shoulder of said plate, more particularly on a shoulder of said orifice of the plate.

[0080] Preferably, the fluidic experimentation device plate according to the invention comprises an accessory in which said substantially annular interface is arranged to pivot around a vertical axis of rotation, centered at the center of a light beam.

[0081] Advantageously, the fluidic experimentation device plate according to the invention comprises an accessory in which said substantially annular interface is arranged to pivot around said vertical axis of rotation when the peripheral lip of said substantially annular interface rests on said shoulder of the orifice of said plate.

[0082] Preferably, the fluidic experimentation device plate according to the invention comprises an accessory comprising mutual control means connected to said substantially annular interface, said mutual control means being arranged to be engaged in control means arranged to be arranged on the plate, and to impart a rotational movement of an amplitude preferably between +30° and -30°, preferably between +20° and -20°, more particularly between +15° and -15°, to said substantially annular interface.

[0083] Advantageously, the fluidic experimentation device plate according to the invention comprises an accessory in which said collector is arranged to be fixed to said substantially annular interface or to said plate.

[0084] Equally advantageously, the fluidic experimentation device plate according to the invention comprises an accessory in which said collector has at least one end-to-end dimension L3 chosen from a width, a length or a diameter and in which said sample holder has at least one end-to-end dimension L2 chosen from a width, a length or a diameter with L3 > L2.

[0085] Preferably, the fluidic experimentation device plate according to the invention comprises an accessory in which said collector has a surface S3 projected by a normal projection on a horizontal plane and said sample holder has a surface S2 projected by a normal projection on a horizontal plane, with S3>S2.

[0086] Preferably, the fluidic experimentation device plate according to the invention comprises an accessory in which the housing for said microfluidic chip has two longitudinal walls which have an intersection (i) with a periphery of said sample holder so as to form a slide.

[0087] Advantageously, the fluidic experimentation device plate according to the invention comprises an accessory comprising a connector provided with pins arranged on said sample holder, said pins being arranged to be connected to electrodes for microfluidic chips, possibly through said microfluidic chip, said connector provided with pins being arranged to be pivotally mounted transversely relative to a median plane of said wall.

[0088] Preferably, the fluidic experimentation device plate according to the invention comprises an accessory further comprising a cassette (24) arranged to house said microfluidic chip and possibly one or more electrodes, said cassette comprising at least one light passage orifice as well as at least one fluid passage orifice arranged to be in fluid communication with a fluid inlet or outlet of a microfluidic chip.

[0089] Advantageously, the orifice of the plate of the microfluidic experimentation device has an outline of the hollowed-out part which is ovoid in shape.

[0090] Equally advantageously, the outline of the hollowed-out portion is circular in shape, trimmed on either side in a substantially rectilinear manner on each side of an axis of symmetry at the same distance. Thus, the hollowed-out portion fits into a circle of diameter equal to the length of the hollowed-out portion of the plate, but it has a width less than the diameter of the circle in which the hollowed-out portion fits.

[0091] If a shoulder is present, it borders the recessed portion and is a shoulder formed in the thickness of the plate and makes it possible to house the sample holder which then rests on a flat portion of the shoulder or to house the substantially annular interface of the accessory according to the present invention.

[0092] In a variant, the plate of the microfluidic experimentation device comprises, not a shoulder, but a thinned zone which borders the hollowed-out part. Similarly, the thinned zone makes it possible to house the sample holder which then rests on the thinned part bordering the hollowed-out part of the plate or to house the substantially annular interface of the accessory according to the present invention. The length of the recessed portion of the orifice is 0.1 to 5 mm greater than that of the substantially annular interface, preferably 0.2 to 3 mm greater than that of the substantially annular interface, more particularly 0.3, 0.5, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2 mm greater than that of the substantially annular interface.

[0093] The width of the recessed portion of the platen orifice is 0.1 to 5 mm greater than that of the substantially annular interface, preferably 0.2 to 3 mm greater than that of the substantially annular interface, more particularly 0.3, 0.5, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2 mm greater than that of the substantially annular interface.

[0094] On either side of the axis of symmetry of the orifice of the plate, the orifice is widened so as to allow rotation of the substantially annular interface. Thus, the contour of the hollowed-out part of the orifice of the plate has an eccentric part on each side of the axis of symmetry. The distance between each of the most extreme points of the eccentric part and the center of rotation is slightly greater than the radius of the circle in which the orifice of the plate is inscribed.

[0095] The eccentric portion of the plate orifice is arranged to allow rotation of the substantially annular interface.

[0096] More particularly, in an advantageous form of the present invention, said substantially annular interface is arranged to pivot about said vertical axis of rotation when the peripheral lip of said substantially annular interface rests on said shoulder of the orifice or the thinned portion bordering the orifice of said plate.

[0097] In a particular form of the present invention, the stage of the microscope microfluidic experimentation device is connected to an XY displacement table, making it possible to move the stage of said microfluidic experimentation device horizontally, along a Y axis and along an X axis. Typically, a displacement along the X axis is between 1 and 50 (or even 100) mm and a displacement along the Y axis is between 1 and 25 (or even 100) mm.

[0098] More particularly, it is advantageous for said stage to be offset from the XY table, which is operated by control means, electrical or manual, which makes it possible to confine the XY table in a box isolated from the experimental area in which the stage is located and thus, when the experimental device must be used in sterile environments, such as for example under a hood, the mechanical elements remain confined in a box of which only the outer wall must be cleaned and disinfected, thus avoiding having to sterilize the mechanism of the XY table. In addition, the space under the stage is thus cleared, as well as the experimental area.

[0099] Advantageously, the receptacle has a vertical dimension greater than the predetermined thickness (e). The receptacle has one or more walls which form a continuous receptacle wall so as to confine a fluid and thus collect it. This continuous wall extends beyond the predetermined thickness (e).

[0100] The sample holder, the interface and the collector have, when assembled, a thickness (f) which is greater than or equal to said predetermined thickness (e). The continuous wall of the receptacle also advantageously extends beyond the thickness (f). Preferably, the receptacle has a bottom which is arranged to end near the optical parts of the microfluidic microscope experimentation device, under the stage thereof.

[0101] For example, the receptacle extends lower than the sample holder. This allows the receptacle volume to be increased and more fluid to be collected. In fluidic experiments, the microfluidic chip can be connected to fluid reservoirs, and these fluids flow in and out of the chip during the experiment. It is possible that any leakage may not be directly detected, and it is important to be able to collect a relatively large amount of fluid, typically more than the volume of fluid contained in the microfluidic chip, without this fluid overflowing from the receptacle.

[0102] Other embodiments of the microscope microfluidic experiment device stage are indicated in the appended claims.

[0103] The present invention also relates to a microfluidic microscope experimentation device comprising a stage according to the present invention, an accessory according to the present invention, an inverted microscopy module formed of a first part comprising at least one objective arranged under the stage and a second part arranged above the stage, said first part being arranged in a box with a pneumatic module, an electronic module equipped with a power supply for the components and signal acquisition means.

[0104] So, for example, under the sample holder is an inverted microscope, containing one or more microscope objectives. The microscope objectives are mounted on a "spindle" for changing objectives. In one embodiment, the spindle is circular; the objectives must be able to "rotate" under the sample holder without hitting the reservoirs. The objective support could also be a longitudinal support on which the objectives are aligned and changed by translation. The reservoirs and anything protruding under the stage cannot be in the space dedicated to the objectives and their rotation / translation, nor to the electronics, optical parts, etc.

[0105] In a preferred embodiment, the microscope microfluidic experimentation device further comprises, in the box, a fluorescence detection module with light excitation comprising one or more excitation sources (for example lasers or photodiodes) and photosensitive sensors (for example photomultiplier tubes), In a preferred embodiment, in the microscope microfluidic experimentation device, said fluidic module comprises connection tubes, reservoirs, ...?

[0106] In a preferred embodiment, the microscope microfluidic experimentation device further comprises mechanical parts and supports, housed in said box, such as, for example, an XY table making it possible to move the stage of said microfluidic experimentation device horizontally, along a Y axis and along an X axis.

[0107] More particularly, it is advantageous for the XY table to be offset from the stage, which XY table is operated by control means, electrical or manual, which makes it possible to confine the XY table in a box, isolated from the experimental area in which the stage is located and thus, when the experimental device must be used in sterile environments, such as, for example, under a hood, the mechanical elements remain confined in a box.

[0108] In a preferred embodiment, in the microscope microfluidic experimentation device, said pneumatic module typically comprising pumps, pressure regulators, (solenoid valves), ...?

[0109] Other embodiments of the microscope microfluidic experimentation device are indicated in the appended claims.

[0110] Description of the invention

[0111] Other characteristics, details and advantages of the invention will emerge from the description given below, without limitation and with reference to the attached drawings.

[0112] Figure 1 is a perspective view of a microfluidic experimentation device according to the invention.

[0113] Figure 2 is a view of the microfluidic experiment device stage accessory.

[0114] Figure 3 is a view of a cassette for containing a microfluidic chip according to the present invention.

[0115] Figure 4 is an exploded view showing the accessory according to the present invention and the microfluidic experiment device stage. Figure 5 illustrates the interface of the stage accessory housed in a hole of the microfluidic experiment device stage with the manifold.

[0116] In the figures, identical or similar elements bear the same references.

[0117] Figure 1 illustrates a microfluidic experimentation device with an inverted microscope comprising an experimentation zone 1 where there is a stage 2 provided with a stage orifice 3 formed by a hollowed-out part through which light can pass. The microfluidic experimentation device comprises, under the stage, a box 4 in which there are a pneumatic module, an electronic module equipped with a power supply for the components and signal acquisition means, possibly a fluorescence detection module with light excitation comprising one or more excitation sources, for example one or more lasers or photodiodes and photosensitive sensors, for example photomultiplier tubes and mechanical parts and supports, housed in said box, such as for example an XY table making it possible to move the stage of said microfluidic experimentation device horizontally, along a Y axis and along an X axis.

[0118] The microfluidic experimentation device also comprises a rotating cover 5 hinged on the box 4 which covers the experimentation area 1, this allows the cover to be opened to set up the microfluidic experimentation and then to close it during the fluidic experimentation for an experimentation without stray light. In addition, in this way, the experimentation is confined, the user is protected from leaks / jets of liquid, but is also prevented from touching the electrodes during the experimentation when they are in use. Finally, the microfluidic experimentation (connection, etc.) is protected from possible contact or shock by the user, which is all the more useful when the samples tested are very rare.

[0119] The experimental zone 1 is delimited by the plate 2 which serves as its bottom and at the rear of the plate 2 is a wall 6 of the box 4. The wall 6 of the box 4 comprises connectors 7, the exposed part of which on the side of the experimental zone makes it possible to connect connection tubes to inlets or inlet reservoirs of the microfluidic chip 8. The unexposed part is located in the box 4 and makes it possible to connect the connectors to the pneumatic module.

[0120] Thus, in the illustrated embodiment, the XY table is offset from the stage 2 and is located in the box 4, isolated from the experimental zone 1 in which the stage 2 is located and thus, when the experimental device must be used in sterile environments, such as for example under a hood, the mechanical elements remain confined in the box 4.

[0121] The microfluidic experimentation device also comprises a screen 9 and housings 10 for reservoirs 11. The housings 10 for reservoirs 11 are located under the cover 5 so that it can be easily closed while maintaining the connections between them and the inputs and outputs of the chip 8 and to confine the microfluidic experimentation as well as the reservoirs and their connections in the dark while carrying out the experiment. The housings 10 for reservoirs 11 are preferably provided with a solid bottom in order to prevent fluids from spreading into the experimentation zone 1 and into the sensitive components (electronic, optical) contained in the box 4, for example by passing under the plate 2.

[0122] Preferably, the housings 10 for the tanks 11 are also arranged next to the plate 2, but under the cover 5.

[0123] The microfluidic experimentation device also comprises an inverted microscopy module formed of a first part, comprising at least one objective 12, arranged under the stage 2 and a second part 13 arranged above the stage 2, said first part 12 being arranged in the box 4, in such a way that said at least one objective 12 can be aligned under the orifice 3 of the stage 2.

[0124] The second part 13 is a light source which is pivotally mounted so that it can be folded down and not hinder the user during the assembly of the microfluidic experiment. When the second part is in the experimental position, that is to say when the light beam is aligned with an objective of the inverted microscope, a magnet blocks the free rotation of the latter. The second part 13 is fixed to the wall 6 of the box, which is also confined under the cover 5.

[0125] The illustrated experimental device further comprises an accessory 14 for stage 2 comprising at least one sample holder 15 detachable from the stage and arranged to be connected to said stage 2. More precisely, the sample holder is housed at least partially in the orifice 3 of the stage. The accessory in the preferred form illustrated also comprises a substantially annular interface 16 and a collector 17.

[0126] Figure 2 shows the sample holder more precisely, while Figure 4 shows the collector more precisely.

[0127] As can be seen in Figure 2, the sample holder 15 comprises a wall 18 of a predetermined thickness e. The sample holder 15 has at least one housing 20 for at least one microfluidic chip 8. The housing 20 is formed in the thickness e of said wall 18 and has a bottom wall 19 provided with a light passage orifice. The bottom wall 1 of the housing 20 being arranged to form a support wall for said at least one microfluidic chip 8. The sample holder also comprises a series of orifices 21, each orifice 21 being arranged to receive a fluid reservoir.

[0128] Thus, fluidic reservoirs 22 can be placed in the orifices 21 of the series of orifices close to the microfluidic chip 8. This proximity makes it possible to reduce the length of the connecting tubes or tubing between the microfluidic reservoirs 22 and the inlets / outlets of the microfluidic chip 8.

[0129] Thus, by being on the same sample holder, the connections between the reservoirs and the microfluidic chip can be made elsewhere than on the experimental device, such as, for example, on a laboratory bench or under a fume hood.

[0130] As can be seen in Figure 2, the housing 20 for the microfluidic chip 8 has two longitudinal walls 23 which have an intersection i with a periphery of said sample holder 15 so as to form a slide. The stage accessory further comprises a cassette 24 (also illustrated in Figure 3) which is arranged to house a microfluidic chip 8 and possibly an electrode 25. The cassette comprises at least one light passage orifice 26 as well as at least one fluid passage orifice 27 arranged to be in fluid communication with a fluid inlet or outlet of a microfluidic chip 8.

[0131] As can be seen more precisely in Figure 4, the collector 17 of the accessory comprises at least one receptacle 30 open on top, arranged to be placed under a first sub-series of orifices of said series of orifices 21, said receptacle 30 being arranged to collect a fluid and allow the passage of light.

[0132] According to the present invention, the collector 17 is arranged to allow the passage of light, this means that it can for example have a light passage orifice 31 and / or that it can extend under a part of the orifice 3 of the plate 2, or under the entirety of the orifice 3 of the plate 2, or even extend over a surface which is greater than the surface of the orifice 3 of the plate 2. In the illustrated embodiment, the collector 17 is annular in shape, it comprises a hollowed-out part and a receptacle 30 molded in one piece with the annular part. The collector is of a shape complementary to a drip wall 41 on which the hollowed-out part is superimposed.

[0133] The collector 17 illustrated therefore comprises a receptacle 30 open on top at its upper edge 39. An annular horizontal wall 40 extends from the upper edge 39. The horizontal wall 40 is arranged to lie beneath the substantially annular interface 16, without moving the wall 18 of the sample holder 15 considerably away from the objectives. The horizontal wall 40 partially closes the hollowed-out part of the plate 2

[0134] As can be seen in more detail in Figure 5, below the horizontal wall 40 of the collector 17, the collector 17 is connected to, or comprises the drip wall 41, preferably inclined at an angle of between 5 and 30°, from which extends upwards a peripheral edge 42 forming a drip tray. The drip wall 41 is arranged to divert into a peripheral zone 43 any fluids from an area surrounding a relatively central light passage orifice 43. The peripheral edge 42 makes it possible to keep the fluid confined in the drip tray. The drip tray also partially closes the hollowed-out portion of the plate 2, in such a way that the hollowed-out portion of the plate is substantially closed by the horizontal wall 40 and the drip wall 41.

[0135] The horizontal wall 40 is housed in the orifice 3 of the plate 2, under the substantially annular interface 16, the horizontal wall 40 and the substantially annular interface 16 together have a thickness substantially equal to the height of the shoulder, so that when they are placed in the orifice, resting on the shoulder of the plate, the upper wall of the substantially annular interface is flush with the surface of the plate, without presenting any difference in level.

[0136] It can thus be envisaged that from the horizontal annular wall a lip extends outwards, and from the upper edge of the peripheral edge 42, a lip extends outwards. The two lips are arranged to form a wall to be fixed under the substantially annular interface 16.

[0137] In the illustrated embodiment, the drip wall 41 is integral with the plate 2, while the collector assembly 17, substantially annular interface 16, sample holder 15 move together during the translational movement along the X and Y axes. Consequently, the movement of the plate 2, dictated by the XY table, is limited so that the wall of the receptacle 30 does not strike the optics of the box. However, in the box, an empty space is provided to accommodate the receptacle 30 and allow its movement along the X and Y axes.

[0138] The substantially annular interface 16 is illustrated in more detail in Figure 5. As can be seen, it has an outer contour 32 described by the outer perimeter of the interface and an inner contour 33, which forms the perimeter of a recessed portion. The length of the outer contour is greater than the length of the inner contour. The outer contour describes a different shape than the shape of the inner contour.

[0139] The substantially annular interface 16 comprises a peripheral lip 34 arranged to rest on a shoulder 35 of a plate 2, preferably on a shoulder 35 forming the circumference of the orifice of the plate, without however being limited thereto. The substantially annular interface 16 is arranged to pivot about a vertical axis of rotation, centered at the center of a light beam oriented from bottom to top if the beam comes from an inverted microscope and oriented from top to bottom if the beam comes from a non-inverted microscope.

[0140] Indeed, the interface being annular, it surrounds the sample holder and can thus be easily mobilized, either by a movement of the hand, or by a control mechanism. In this latter configuration, the sample holder, once placed in the substantially annular interface, is integral with it under the effect of rotation.

[0141] The external contour 32 of the substantially annular interface is ovoid in shape.

[0142] The orifice 3 of the plate 2 of the microfluidic experimentation device has an outline 36 of the hollowed-out part which is ovoid in shape.

[0143] On either side of an axis of symmetry S of the orifice 3 of the plate 2, the orifice 3 is widened so as to allow the rotation of the substantially annular interface 16. Thus, the outline of the hollowed-out part of the orifice of the plate has an eccentric part 37 on each side of the axis of symmetry S

[0144] The eccentric part 37 of the orifice 3 of the plate 2 is arranged to allow the rotation of the substantially annular interface 16.

[0145] More particularly, in an advantageous form of the present invention, said interface 16 is arranged to pivot around said vertical axis of rotation when the peripheral lip of said substantially annular interface 16 rests on said shoulder 35 of the orifice 3 of said plate 2.

[0146] The plate accessory comprises mutual control means (not visible) connected to said substantially annular interface 16, said mutual control means being arranged to be engaged in control means 38 arranged to be arranged on the plate 2, and to impart a rotational movement of an amplitude preferably between +30° and -30°, preferably between +20° and -20°, more particularly between +15° and -15°, or even between +5° and -5° to said substantially annular interface 16. The collector 17 is fixed to said plate 2, under substantially annular interface 16 in the illustrated embodiment. It is understood that it could also be connected to the substantially annular interface.When the collector 17 is fixed to said substantially annular interface 16, when the latter is moved in rotation, it thus follows the movement of said substantially annular interface 16 and therefore of the sample holder 15 which is housed there so as to be integral in movement with the substantially annular interface 16.

[0147] Advantageously, according to the present invention, said collector has at least one dimension L3 greater than a dimension L2 of the sample holder.

[0148] Preferably, the dimension L3 is also greater than a dimension L1 of the internal contour of the substantially annular interface, so as to be able to fix the collector easily under the substantially annular interface.

[0149] The orifice 3 of the plate 2 of the microfluidic experimental device has an outline of the hollowed-out part which is ovoid in shape.

[0150] The shoulder 2 of the plate borders the hollowed-out portion of the plate 2 and is a shoulder formed in the thickness of the plate. It makes it possible to house the substantially annular interface of the accessory according to the present invention in the illustrated embodiment.

[0151] It is understood that the present invention is in no way limited to the embodiments described above and that many modifications may be made thereto without departing from the scope of the appended claims.

[0152] For example, it is also possible to provide an accessory for a stage of a microfluidic microscope experimentation device comprising: at least one sample holder arranged to be connected to said stage and to be housed at least partially in an orifice thereof, said at least one sample holder comprising a wall of a predetermined thickness, said at least one sample holder being detachable from said stage, said at least one sample holder having:

[0153] (i) at least one housing for at least one microfluidic chip, preferably formed in the thickness of said wall and having a bottom wall provided with a light passage orifice, said bottom wall of the housing being arranged to form a support wall for said at least one microfluidic chip,

[0154] (ii) a series of orifices, each orifice being arranged to receive a fluid reservoir, a substantially annular interface, connecting said sample holder to said plate and, optionally, a collector comprising at least one receptacle open on the top, arranged to be placed under a first sub-series of orifices of said series of orifices, said receptacle being arranged to collect a fluid and allow the passage of light.

Claims

CLAIMS 1. Accessory for a stage (2) of a microfluidic microscope experimentation device comprising at least one sample holder (15) arranged to be connected to said stage (2) and to be housed at least partially in an orifice (3) thereof, said at least one sample holder (15) comprising a wall (18) of a predetermined thickness (e), said at least one sample holder (15) being detachable from said stage (2), said at least one sample holder (15) having: (i) at least one housing (20) for at least one microfluidic chip (8) preferably, formed in the thickness (e) of said wall (18) and having a bottom wall (19) provided with a light passage orifice, said bottom wall (1) of the housing (20) being arranged to form a support wall for said at least one microfluidic chip (8), (ii) a series of orifices (21), each orifice (21) being arranged to receive a fluid reservoir, at least one collector (17) comprising at least one receptacle (30) open on top, arranged to be disposed under a first sub-series of orifices (21) of said series of orifices (21), said receptacle (30) being arranged to collect a fluid and allow the passage of light.

2. Accessory for stage (2) of a microfluidic microscope experimentation device according to claim 1, further comprising a substantially annular interface (16), connecting said sample holder (15) to said stage (2).

3. Accessory for a stage (2) of a microfluidic microscope experimentation device according to claim 2, in which said substantially annular interface (16) comprises a peripheral lip (34) arranged to rest on a shoulder (35) of said plate (2), more particularly on a shoulder (35) of said orifice (3) of the plate (2).

4. Accessory for stage (2) of a microfluidic microscope experimentation device according to claim 2 or claim 3, wherein said substantially annular interface (16) is arranged to pivot around a vertical axis of rotation, centered at the center of a light beam.

5. Accessory for stage (2) of a microfluidic microscope experimentation device according to claims 3 and 4, wherein said substantially annular interface (16) is arranged to pivot about said vertical axis of rotation when the peripheral lip of said substantially annular interface rests on said shoulder of the orifice of said stage.

6. Accessory for a stage (2) of a microfluidic microscope experimentation device according to any one of claims 2 to 5, comprising mutual control means connected to said substantially annular interface (16), said mutual control means being arranged to be engaged in control means (38) arranged to be arranged on the stage (2), and to impart a rotational movement of an amplitude preferably between +30° and -30°, preferably between +20° and -20°, more particularly between +15° and -15°, to said substantially annular interface (16).

7. Accessory for a stage (2) of a microfluidic microscope experimentation device according to any one of the preceding claims, wherein said collector (17) is arranged to be fixed to said substantially annular interface (16) or to said stage (2).

8. Accessory for stage (2) of a microscope microfluidic experimentation device according to any one of the preceding claims, in which said collector (17) has at least one end-to-end dimension L3 chosen from a width, a length or a diameter and in which said sample holder (15) has at least one end-to-end dimension L2 chosen from a width, a length or a diameter with L3 > L2.

9. Accessory for stage (2) of a microfluidic microscope experimentation device according to any one of the preceding claims, in which said collector (17) has a surface S3 projected by a normal projection on a horizontal plane and said sample holder (15) has a surface S2 projected by a normal projection on a horizontal plane, with S3>S2.

10. Accessory for stage (2) of a microfluidic microscope experimentation device according to any one of the preceding claims, in which the housing (20) for said microfluidic chip (18) has two longitudinal walls (23) which have an intersection (i) with a periphery of said sample holder (15) so as to form a slide. 1 1. Accessory for a plate (2) of a microfluidic microscope experimentation device according to any one of the preceding claims, comprising a connector provided with pins arranged on said sample holder (15), said pins being arranged to be connected to electrodes for microfluidic chips (8), possibly through said microfluidic chip (8), said connector provided with pins being arranged to be pivotally mounted transversely relative to a median plane of said wall (18).

12. Accessory for a plate (2) of a microfluidic microscope experimentation device according to any one of the preceding claims, further comprising a cassette (24) arranged to house said microfluidic chip (8) and optionally an electrode (25), said cassette (24) comprising at least one light passage orifice (26) as well as at least one fluid passage orifice (27) arranged to be in fluid communication with a fluid inlet or outlet of a microfluidic chip (8).

13. Plate (2) of a microfluidic microscope experimentation device comprising an accessory according to one of the preceding claims.

14. Stage (2) of a microfluidic experiment device with a microscope according to claim 13, connected to an XY displacement table, making it possible to move the stage (2) of said microfluidic experiment device horizontally, along a Y axis and along an X axis.

15. Stage (2) of a microfluidic microscope experimentation device according to claim 14, in which said stage (2) is offset from the XY table, which is actuated by electrical or manual control means.

16. Microfluidic experimentation device comprising: A plate (2) according to any one of claims 13 to 15, An accessory for a stage (2) according to any one of claims 1 to 12, an inverted microscopy module formed of a first part (12) comprising at least one objective (12) arranged under the stage (2) and a second part (13) arranged above the stage (2), said first part (12) being arranged in a box (4) with a pneumatic module, an electronic module equipped with a power supply for the components and means for acquiring and processing signals.

17. Microfluidic experimentation device according to claim 16, further comprising, in the box (4), a fluorescence detection module with light excitation comprising one or more excitation sources, for example one or more lasers or photodiodes and photosensitive sensors, for example photomultiplier tubes.

18. Microfluidic experimentation device according to claim 16 or claim 17, wherein said fluidic module comprises connecting tubes, reservoirs.

19. Microfluidic experimentation device according to any one of claims 16 to 18, further comprising mechanical parts and supports, housed in said box (4), such as, for example, an XY table, preferably offset from the plate (2), said XY table being actuated by control means, electrical or manual, 20. Microfluidic experimentation device according to any one of claims 16 to 19, wherein said pneumatic module typically comprises pumps and / or pressure regulators and / or solenoid valves.