Microfluidic component adapted for characterizing a biological object

Abstract

The invention relates to a microfluidic component used for electrical impedance measurement through a biological object (O), said microfluidic component comprising: A support in which is made a main microfluidic channel (C_1) defining a path for the circulation of a fluid containing the biological object (O), A trapping device positioned in the main microfluidic channel (C_1) on the circulation path of said biological object, At least one first electrode and a second electrode intended to be each set at a distinct electrical potential, in order to perform said impedance measurement, Said trapping device being composed of at least one first central pillar (P_1) and a second central pillar (P_2) positioned inside the microfluidic channel, The first central pillar being configured to form the first electrode and the second central pillar being configured to form the second electrode.Figure to be published with the abbreviation: Figure 2.

Description

Title of the invention: Microfluidic component adapted for characterizing a biological object. Technical field of the invention

[0001] The present invention relates to a microfluidic component used for electrical impedance measurement through a biological object, this component being able to be used to characterize the biological object, in particular for the purpose of studying its viability. State of the art

[0002] Studies are currently underway to better characterize a biological object such as a spheroid formed by a cluster of biological cells. This characterization focuses in particular on the viability of the biological cells that compose the spheroid. Studies show that there may be a correlation between the viability of the cells present in the spheroid and electrical impedance measurements across the spheroid. Transepithelial / transendothelial electrical resistance (TEER) is a widely accepted quantitative technique for measuring the integrity of tight junction dynamics in cell culture models of endothelial and epithelial monolayers. TEER values ​​are good indicators of the integrity of cell barriers before they are evaluated for the transport of drugs or chemicals.TEER measurements can be performed in real time without damaging the cells and are generally based on measuring ohmic resistance or impedance over a wide frequency spectrum.

[0003] In other words, the higher the electrical impedance measured across the spheroid, the more living cells the spheroid would contain. Although this relationship is not yet fully established, numerous studies are attempting to demonstrate it. These studies rely on the use of microfluidic devices for measuring electrical impedance. The following studies are particularly noteworthy: - Wu_20I8 - Electrical impedance tomography for real-time and label- free cellular viability assays of 3D tumor spheroids - Analyst / University of Edinburgh.# - Viswam_2018 - Impedance Spectroscopy and Electrophysiological Imaging of cells with a high-density CMOS microelectrode array System - IEEE Transactions on biomedical circuits and systems / Ecole Polytechnique de Zurich (ETH)# - Heileman_2015 - Microfluidic platform for assessing pancreatic islet functionality through dieletric spectroscopy - Biomicrofluidics / McGill University, Montreal#

[0004] However, the various devices used in these studies are not satisfactory for the following reasons: - The electrodes used are coplanar, and the biological objects to be characterized are either in contact with the electrodes or too far away. In some cases, the field lines produced between the electrodes will not optimally penetrate the biological objects to be characterized. The materials used for integrating electrodes into these fluidic systems are often not transparent (electrode or chamber materials), or the device configuration is not suitable for visualizing and monitoring the biological object. It is often impossible to implement transmission microscopy monitoring, even though this observation method is a standard in biology. - They are not suitable for setting up an infusion of the trapped biological object.

[0005] US patent 8454813B2 describes a cell sorting device (cytometer). This device is not intended to characterize a biological object through measurements. The electrodes are positioned so that the created field forces the cell against the bottom of the well.

[0006] US patent application 2010 / 270176A1 describes a device for characterizing neurons. This device uses coplanar electrodes arranged at the bottom of the cavity. This solution allows the biological object to be pressed against the bottom of the cavity, which is not optimal for characterizing it through measurements.

[0007] Patent EP4147780B1 describes the principle of characterizing a biological object by impedance measurements, using electrodes integrated into the support. The electrodes are made in the form of conductive deposits and are arranged so that the field lines pass through the biological object.

[0008] This latter solution, however, presents certain drawbacks. It does not allow for measurements to be taken very close to the biological object. Its architecture does not allow for perfusion of the trapped biological object. It is also not suitable for monitoring the fluidic environment surrounding the biological object.

[0009] The object of the invention is to provide a microfluidic component that allows for the characterization of a biological object and that is: - Suitable for performing reliable electrical impedance measurements as close as possible to the biological object; - Adapted to allow perfusion of the biological object; - Achievable using already mastered manufacturing technologies; - Possibly adapted to monitor the fluidic environment surrounding the biological object; Description of the invention

[0010] This objective is achieved by a microfluidic component used for measuring electrical impedance across a biological object, said microfluidic component comprising: - A support in which a main microfluidic channel is created, defining a path for the circulation of a fluid containing the biological object, - A trapping device positioned in the main microfluidic channel along the flow path of said biological object, - At least one first electrode and a second electrode, each intended to be placed at a distinct electrical potential, for the purpose of carrying out said impedance measurement, - Said trapping device being composed of at least one first central pillar and a second central pillar positioned inside the microfluidic channel, - The first central pillar is configured to form the first electrode and the second central pillar is configured to form the second electrode.

[0011] According to one particular feature, the first electrode is placed at a first positive or negative electrical potential and the second electrode is placed at a second electrical potential, respectively negative or positive.

[0012] According to another feature, the main microfluidic channel extends lengthwise along a longitudinal axis and has a constant cross-section over at least part of its length, the first central pillar and the second central pillar being positioned symmetrically on either side of said longitudinal axis.

[0013] According to a particular embodiment, the trapping device comprises a third central pillar and a fourth central pillar positioned symmetrically on either side of said longitudinal axis, the third central pillar being located on the same side with respect to the longitudinal axis as the first central pillar and the fourth central pillar on the same side as the second central pillar.

[0014] According to one particular feature, the third central pillar is configured to form a third electrode and the fourth central pillar is configured to form a fourth electrode.

[0015] According to another particular embodiment, the trapping device comprises a fifth central pillar, called the median pillar, positioned along the longitudinal axis, the middle pillar being configured to form a fifth electrode, intended to be brought to a neutral electrical potential.

[0016] According to a particular embodiment, the central pillars of the trapping device are positioned along an arc of a circle.

[0017] According to a particular embodiment, the central pillars of the trapping device each have a circular cross-section.

[0018] According to another particular embodiment, the first central pillar and the second central pillar each have a kidney-shaped cross-section.

[0019] According to another particular embodiment, the support comprises a first lateral channel connected to the main microfluidic channel by a first junction zone and a second lateral channel connected to the main microfluidic channel by a second junction zone, the first junction zone and the second junction zone being located opposite the trapping device.

[0020] According to another particular embodiment, the component comprises a first series of one or more lateral pillars positioned at the level of the first junction zone and a second series of one or more lateral pillars positioned at the level of the second junction zone, each lateral pillar of the first series and of the second series being configured to form a separate electrode intended to be brought to an electrical potential.

[0021] According to another particular embodiment, each lateral pillar of the first series is placed at a first positive or negative electrical potential and each lateral pillar of the second series is placed at a second electrical potential, respectively negative or positive.

[0022] According to a particular feature, each lateral pillar has a triangular cross-section.

[0023] According to a particular feature, each lateral pillar has a hemicylindrical shape.

[0024] According to a particular embodiment, the support comprises an intermediate layer made of a doped silicon-type material, said intermediate layer being configured to make each pillar.

[0025] According to one particular feature, the intermediate layer comprises a body made around said pillars, configured to be electrically insulating.

[0026] The invention also relates to a system for measuring electrical impedance through a biological object comprising a microfluidic component and a potentiostat, the microfluidic component being as defined above, each electrode being connected to said potentiostat to be held at an electrical potential. Brief description of the figures

[0027] Other features and advantages will become apparent in the detailed description that follows, in conjunction with the attached figures listed below: - Fig. 1 illustrates, seen in perspective, the principle of realization of the microfluidic component according to the invention, according to a first example of realization; - Fig. 2 represents, seen from above, the microfluidic component according to the invention in the first embodiment; - Figures 3A to 3F show different configurations of the microfluidic component; - Figures 4A to 4D illustrate, through current density simulations, the targeted area of ​​interest according to several distinct electrical configurations; - Fig. 5 represents an example of the realization of the multilayer structure of the microfluidic component support;

[0028] Detailed description of at least one embodiment

[0029] In the following description, the terms "lower", "upper", "above", "below" or equivalent are to be considered taking into account the position of the microfluidic component on a horizontal support.

[0030] The term "longitudinal" is to be understood in the directions parallel to the horizontal support and the term "transverse" in the directions perpendicular to the horizontal support.

[0031] The invention aims in particular to enable the measurement of electrical impedance through a biological object O.

[0032] The biological object O is, for example, a cell aggregate. According to the invention, a cell aggregate is understood to be the self-assembly of one or more cell types in three dimensions. Such a cell aggregate may, in particular, be called a spheroid, organoid, tumoroid, or neurosphere. This aggregate may also be an islet of Langerhans. In the remainder of this description, the term "biological object," referenced as O, will be used generically to refer to such an aggregate, this term being commonly used in the field of live cell culture. Without limitation, such a biological object O may, for example, have a diameter ranging from a few tens of micrometers to a few hundred micrometers. Microfluidic component

[0033] [Fig.1]

[0034] [Fig.2]

[0035] The microfluidic component of the invention includes a support.

[0036] The support may comprise a multi-layered structure (see below in conjunction with [Fig.5]).

[0037] The microfluidic component support includes a main microfluidic channel C_l.

[0038] This channel advantageously has a rectangular cross-section. It extends in a straight line along a designated longitudinal axis (X). It is designed to form a flow path for the biological object O to be analyzed. It thus comprises an inlet through which the biological object O is introduced, and an outlet.

[0039] The component also includes a biological object trapping device, positioned inside the main microfluidic channel C_l, between its inlet and outlet.

[0040] According to the invention, the trapping device comprises at least two first pillars, referred to as central pillars P_1, P_2, erected in the main microfluidic channel C_1, interposing themselves in the fluidic flow. These central pillars P_1, P_2 are erected (in a transverse direction) in the main microfluidic channel and are positioned so as to block the biological object O when it is injected into the main microfluidic channel along the longitudinal axis (X).

[0041] Advantageously, the two central pillars P_l, P_2 are positioned symmetrically, on either side of the longitudinal axis (X) of the main microfluidic channel C_l.

[0042] In an advantageous embodiment shown in [Fig.1] and [Fig.2], the trapping device comprises four central pillars P_1, P_2. These four central pillars are also advantageously positioned symmetrically, two by two, on either side of the longitudinal axis (X) of the main microfluidic channel.

[0043] In another configuration, it is also possible to integrate a fifth central pillar, called the median pillar P_3, into the trapping device, positioned along the longitudinal axis (X) ([Fig.3F] below).

[0044] According to an advantageous configuration, the central pillars of the trapping device are positioned to form an arc of a circle. The arc of a circle is formed to create a concavity to receive the biological object O as it flows from the inlet to the outlet of the main microfluidic channel C_l.

[0045] According to a particular embodiment, the component can integrate into its support one or more lateral microfluidic channels C_20, C_30, each lateral channel having at least one junction zone Z_20, Z_30 with the main microfluidic channel C_1, through which it communicates with the main microfluidic channel C_1. In Figures 1 and 2, two lateral channels C_20, C_30 are shown. Each lateral microfluidic channel C_20, C_30 is advantageously used to transport a culture medium suitable for the perfusion of the biological object O trapped by the trapping device. According to one embodiment, each junction zone Z_20, Z_30 is thus located opposite the trapping zone of the biological object O.

[0046] According to a particular and advantageous embodiment, the component comprises a series of one or more lateral pillars P_20, P_30 at each junction zone Z_20, Z_30 existing between a lateral microfluidic channel C_20, C_30 and the main microfluidic channel C_1. In other words, with two lateral microfluidic channels, two series of one or more lateral pillars are present at each junction zone. The two series of one or more lateral pillars are positioned symmetrically with respect to the longitudinal axis (X). Without limitation, the first series may comprise five lateral pillars P_20 and the second series may comprise five lateral pillars P_30. The lateral pillars P_20 of the first series and the lateral pillars P_30 of the second series are positioned symmetrically with respect to the longitudinal axis (X). In each series, the lateral pillars are advantageously aligned along a direction parallel to the longitudinal axis (X).

[0047] According to the invention, the component also incorporates several electrodes, used to perform impedance measurements across the biological object O when it is trapped by the trapping device. The electrodes are polarized and are therefore placed, in pairs, at distinct and opposite electrical potentials.

[0048] By opposite electrical potentials, it is understood that the two potentials have the same magnitude but opposite signs (one is positive and the other is negative). For example, the positive electrical potential is set at +10 mV and the negative electrical potential is set at -10 mV. In the measurement technique used, namely electrochemical impedance spectroscopy, a sinusoidal potential is applied that oscillates between +10 and -10 mV.

[0049] According to the invention, each central pillar P_1, P_2 of the trapping device is configured to form a separate electrode.

[0050] In the case where lateral pillars P_20, P_30 are present, these are each configured to form a separate electrode.

[0051] Each electrode of the component can be placed at a distinct electrical potential.

[0052] In the following description, it is thus considered that, since each pillar is configured to form an electrode, it can be placed at a particular electrical potential.

[0053] To set each pillar to an electrical potential, the microfluidic component is connected to a potentiostat, to the terminals of which each electrode of the component is connected. The potentiostat is configured to regulate the electrical potential applied to each electrode. The potentiostat and the component thus form a complete measurement system for performing impedance measurements on the biological object.

[0054] Advantageously, several options can be considered: - The lateral pillars P_20 of the first series are placed at the same electrical potential; - The lateral pillars P_30 of the second series are placed at the same electrical potential; - The lateral pillars P_20 of the first series and the lateral pillars P_30 of the second series are at the same electrical potential or at opposite electrical potentials; - The central pillars P_1, P_2 (with the exception of the middle pillar P_3) are placed at the same electrical potential; - The central pillars are divided into a first series (pillars P_1) at a first electric potential and a second series (pillars P_2) at a second electric potential opposite to the first electric potential; - The central pillar P_3 is placed at a neutral electrical potential;

[0055] By playing with these different options, we can thus change the configuration of the device and focus the analysis on one or more areas of interest.

[0056] Depending on the electrical potentials assigned to each pillar, different field lines are created, thus allowing the characterization of the biological object O and / or its surrounding environment. According to the invention, it is possible to activate each electrical potential independently and to create one or more field lines in the component. The various impedance measurements taken between two pillars are data collected for analysis. A processing unit can be configured to analyze this measurement data and determine properties of the trapped biological object O and / or its surrounding environment. Layout configurations

[0057] Figures 3A to 3F

[0058] In conjunction with the accompanying figures, several configurations can thus be envisaged, without limitation. These configurations are given by way of example and are to be considered in a non-limiting manner.

[0059] First configuration - [Fig. 3A]: This is the simplest configuration, allowing the biological object O to be trapped while measurements are taken as close as possible to it. This configuration thus incorporates only two central pillars P_1, P_2, placed at two distinct and opposite electrical potentials (+10 mV and -10 mV). They are positioned symmetrically with respect to the longitudinal axis.

[0060] Second configuration - [Fig.3B]: this is a configuration with only four central pillars, a first series of two central pillars P_1 located on the same side of the longitudinal axis (X) being at the same first electrical potential (for example +10mV), and a second series of two central pillars P_2 located on the other side of the longitudinal axis (X) at a second electrical potential (for example -10mV), opposite to that of the first electrical potential.

[0061] Third configuration - [Fig.3C]: Four central pillars P_1, P_2 in two series (as in the second configuration) and at least two lateral pillars P_20, P_30, a first lateral pillar P_20 at the level of the first junction zone Z_20 and a second lateral pillar P_30 at the level of the second junction zone Z_30. The two central pillars P_1 of the first series, located on the same side of the longitudinal axis (X), are at the same first electrical potential (for example +10mV), and the two central pillars P_2 of the second series, located on the other side of the longitudinal axis (X), are at the same second electrical potential (for example -10mV), opposite to that of the first electrical potential.

[0062] The two lateral pillars P_20 and P_30 each have a distinct electrical potential, with the two electrical potentials being opposite. The lateral pillar P_20 is at the same electrical potential (+10mV) as the central pillars P_1 of the first series. The lateral pillar P_30 is at the same electrical potential (-10mV) as the central pillars P_2 of the second series.

[0063] Fourth configuration - [Fig. 3D]: This is identical to the third configuration, with several lateral pillars P_20, P_30 for each series. In [Fig. 3D], five lateral pillars are used for each series of lateral pillars. The lateral pillars P_20 of the first series are all at the same electrical potential (e.g., +10mV), and the lateral pillars P_30 of the second series are all at the same electrical potential (e.g., -10mV), opposite to that applied to the pillars of the first series. The pillars (central and lateral) located on the same side of the longitudinal axis (X) are all at the same electrical potential, and the pillars located on the other side of the longitudinal axis (X) are at the opposite electrical potential.

[0064] Fifth configuration - [Fig. 3E]: Its structure is identical to that of the fourth configuration. However, the lateral pillars P_20 of the first series and those (P_30) of the second series are all at the same electrical potential (for example, +10 mV). And the central pillars P_1, P_2 are all at the same electrical potential (for example, -10 mV), opposite to that applied to the lateral pillars.

[0065] Sixth configuration: This configuration is identical to the fourth configuration ([Fig. 3D]), with the addition of the median pillar P_3 located in the axis of the longitudinal channel (X). This pillar is placed at a neutral electrical potential (0mV). Manufacturing principles

[0066] [Fig.5]

[0067] To form an electrode at the level of a pillar of the component, several solutions can be considered.

[0068] One solution would be to apply a metallic coating to each pillar and integrate a via into the support to connect each pillar to the potentiostat. In this case, the intermediate layer incorporating the pillars could be made of silicon and A cavity is drilled into each pillar to allow for the application of a metallic coating. Alternatively, a metallic layer could be deposited directly onto the surface of each pillar. The metal could be replaced by a metal oxide, a conductive material such as graphene, amorphous carbon (DLC), a material like indium oxide (ITO) or molybdenum disulfide (MoS2), or any other biocompatible electrically conductive material.

[0069] Another advantageous solution, illustrated in [Fig. 5], consists of creating the electrodes using a specific intermediate layer L_2 exhibiting conductive properties. For example, this intermediate layer L_2 incorporates the pillars of the component. It is, for instance, made of doped silicon.

[0070] In this configuration of a conductive intermediate layer, the multilayer structure is, for example, as follows: - A first lower layer L_1 advantageously made of an electrically insulating material, such as CGC for Cyclo Olefin Copolymer, COP for Cyclo Olefin polymer, a PMMA (Polymethyl Methacrylate) type material. - A second layer, forming the intermediate layer L_2 made of doped silicon, this second layer being shaped to create the central and lateral pillars (if present) - designated P_X on the [Fig.5]; - A third layer L_3 made of silica (SiO2) integrating the electrical connections 10 to each pillar; - A fourth layer L_4 forming a hood, made of glass and including the electrical tracks 11;

[0071] The manufacturing principle of the glass (L_4)-pillar interface is, for example, as follows: - Deposition by PVD (vapor phase deposition) of a 20nm titanium adhesion layer on the glass layer; - Deposition by PVD of a layer of Platinum on the Titanium layer; - Deposition of the L_2 layer of doped silicon; - Deposition of a mask on the doped silicon layer to protect the areas intended to form the pillars and electrical connections; - Plasma etching of the L_2 layer of doped silicon to form the pillars;

[0072] By way of non-limiting example, the intermediate silicon layer L_2 is N+ doped with arsenic. Its resistivity is given to be less than 3 mohm.cm.

[0073] As indicated above, the electrical connections / tracks are for example made of platinum or gold.

[0074] It should be noted that when the intermediate layer L_2 is made in the form of doped silicon, the entire intermediate layer L_2 is therefore endowed with conductive properties, and thus also the body of the support in which the main microfluidic channel C_1 and the lateral microfluidic channels C_20, C_30 are formed. However, it is also possible to make this volume electrically insulating and to make only the pillars of the structure conductive.

[0075] By way of non-limitation, the central and lateral pillars can take different forms: - The central pillars P_1, P_2 can all be identical and cylindrical; - Two central pillars located closest to the longitudinal axis (X) may have a cross-section in the shape of a bean; - The lateral pillars P_20, P_30 may have a triangular cross-section; - The lateral pillars P_20, P30 may have a semicylindrical shape;

[0076] Any other shape could of course be considered. Generally speaking, it may be relevant to avoid shapes with sharp edges, in order to avoid point effects when creating field lines between the pillars.

[0077] Without limitation, the pillars shall have a suitable height, at most equal to the depth of the microfluidic channel and at least equal to half the largest dimension (e.g., its diameter) of the biological object O, in order to maintain an effective trapping function. The cylindrical central pillars, for example, shall have a cross-section of 100 µm in diameter. The height of the triangular cross-section of the lateral pillars shall also be 100 µm. The electrical connections shall be, for example, thin platinum lines, 50 µm wide. The central pillars shall be spaced, for example, 80 µm apart. And the lateral pillars shall be spaced, for example, 45 µm apart. Functional simulations

[0078] Figures 4A to 4E

[0079] Depending on the chosen geometric and electrical configuration, it is thus possible to observe a specific area of ​​interest (designated Z in the figures). Different configurations are shown below:

[0080] [Fig. 4A]: This is the fourth configuration described above, in which the central pillars p_1, P_2 are chosen to be cylindrical and the lateral pillars p_20, P_30 are semi-cylindrical in shape. The body of the intermediate layer L_2 is electrically insulated. On one side of the longitudinal axis, the two central pillars P_1 and the lateral pillars P_20 are at the same electrical potential (+10 mV) and on the other side of the longitudinal axis, the two other central pillars P_2 and the other lateral pillars P_30 are at the opposite electrical potential (-10mV).

[0081] It is noted that the impedance measurement at 1MHz is concentrated on a zone Z which typically corresponds to the zone where the biological object O is positioned when it is trapped in the component.

[0082] [Fig. 4B]: This is also the fourth configuration described above, in which triangular-sectioned lateral pillars P_20 and P_30 are used. It can thus be seen that it is possible to focus the measurements on a zone Z that corresponds to the trapping zone of the biological object.

[0083] [Fig. 4C]: The same geometric and electrical configuration as in [Fig. 3E] is maintained. All central pillars P_1, P_2 are set to the same electrical potential (e.g., -10 mV), and all lateral pillars P_20, P_30 are set to the opposite electrical potential (+10 mV). Numerical simulations show that, in this configuration, the impedance measurement will preferentially be performed on a zone Z corresponding to that occupied by the surrounding medium, with the exception of the biological object's trapping zone. Such a current distribution is quite useful for performing reference measurements; for example, the solution present in the surrounding medium can be characterized without the biological object O.

[0084] [Fig. 4D]: This is the configuration with five central pillars ([Fig. 3F]), including a central pillar P_3 located on the longitudinal axis and at a neutral electrical potential. The two central pillars P_1 and the lateral pillars P_20 located on the same side of the longitudinal axis (X) are at the same electrical potential (+10 mV), and the two other central pillars P_2 and the other lateral pillars P_30 located on the opposite side of the longitudinal axis (X) are at the opposite electrical potential (-10 mV). The body of the intermediate layer L_2 is electrically isolated. In this configuration, it is possible to study a zone Z, which corresponds to the trapping zone of the biological object.

[0085] [Fig. 4E]: This configuration involves changing the shape of two central pillars P_1, P_2, one pillar from each series, located closest to the longitudinal axis (X). These are shaped into a bean-like form. The lateral pillars P_20, P_30 are chosen with a semi-cylindrical shape. The body of the intermediate layer L_2 is electrically insulated. Electrically, the central pillars P_1 and the lateral pillars P_20 are at the same electrical potential (+10mV), and the central pillars P_2 and the lateral pillars P_30 are at opposite electrical potentials (-10mV). In this configuration, it can be observed that one can focus on a zone Z, which corresponds to the trapping zone of the biological object. Furthermore, less loss is observed with the semi-cylindrical shape of the lateral pillars P_20, P_30.

[0086] The solution of the invention thus makes it possible to fulfill the function of trapping the biological object O as well as the function of impedance measurement, by allowing it to get as close as possible to the trapped biological object O.

[0087] In addition, the different possible connection configurations allow targeting, as desired, different areas of interest, including the biological object or its surrounding environment.

[0088] Finally, manufacturing using an intermediate layer L_2 in doped silicon, this intermediate layer integrating the pillars, simplifies the manufacturing process.

Claims

Demands

1. A microfluidic component used for measuring electrical impedance through a biological object (0), said microfluidic component comprising: - A support in which a main microfluidic channel (C_1) is formed, defining a path for the flow of a fluid containing the biological object (0), - A trapping device positioned in the main microfluidic channel (C_1) on the flow path of said biological object, - At least one first electrode and one second electrode, each intended to be held at a distinct electrical potential, for the purpose of performing said impedance measurement, - Characterized in that: - Said trapping device is composed of at least one first central pillar (P_1) and a second central pillar (P_2) positioned inside the microfluidic channel,- The first central pillar is configured to form the first electrode, and the second central pillar is configured to form the second electrode.

2. Component according to claim 1, characterized in that the first electrode is set at a first positive or negative electrical potential and in that the second electrode is set at a second electrical potential, respectively negative or positive.

3. Component according to any one of claims 1 or 2, characterized in that the main microfluidic channel (C_1) extends lengthwise along a longitudinal axis (X) and in that it has a constant cross-section over at least part of its length, the first central pillar (P_1) and the second central pillar (P_2) being positioned symmetrically on either side of said longitudinal axis.

4. Component according to claim 3, characterized in that the trapping device comprises a third central pillar and a fourth central pillar positioned symmetrically on either side of said longitudinal axis (X), the third central pillar being located on the same side with respect to the longitudinal axis (X) as the first pillar central and the fourth central pillar on the same side as the second central pillar.

5. Component according to claim 4, characterized in that the third central pillar is configured to form a third electrode and the fourth central pillar is configured to form a fourth electrode.

6. Component according to claim 4 or 5, characterized in that the trapping device comprises a fifth central pillar, called median pillar (P_3), positioned along the longitudinal axis (X), the median pillar being configured to form a fifth electrode, intended to be placed at a neutral electrical potential.

7. Component according to any one of claims 1 to 6, characterized in that the central pillars (P_1, P_2, P_3) of the trapping device are positioned along an arc of a circle.

8. Component according to any one of claims 1 to 7, characterized in that the central pillars (P_1, P_2, P_3) of the trapping device each have a circular cross-section.

9. Component according to any one of claims 1 to 7, characterized in that the first central pillar (P_1) and the second central pillar (P_2) each have a kidney-shaped cross-section.

10. Component according to any one of claims 1 to 9, characterized in that the support comprises a first lateral channel (C_20) connected to the main microfluidic channel (C_1) by a first junction zone (Z_20) and a second lateral channel (C_30) connected to the main microfluidic channel (C_1) by a second junction zone (Z_30), the first junction zone and the second junction zone being located opposite the trapping device.

11. Component according to claim 10, characterized in that it comprises a first series of one or more lateral pillars (P_20) positioned at the level of the first junction zone (Z_20) and a second series of one or more lateral pillars (P_30) positioned at the level of the second junction zone (Z_30), each lateral pillar (P_20, P_30) of the first series and of the second series being configured to form a separate electrode intended to be brought to an electrical potential.

12. Component according to claim 11, characterized in that each lateral pillar (P_20) of the first series is set to a first positive or negative electrical potential and each lateral pillar (P_30) of the second series is put at a second electrical potential, respectively negative or positive.

13. Component according to claim 11 or 12, characterized in that each lateral pillar (P_20, P_30) has a triangular cross-section.

14. Component according to claim 11 or 12, characterized in that each lateral pillar (P_20, P_30) has a semicylindrical shape.

15. Component according to any one of claims 1 to 14, characterized in that the support comprises an intermediate layer (L_2) made of a doped silicon-type material, said intermediate layer (L_2) being configured to perform each pillar (P_1, P_2, P_3, P_20, P_30).

16. Component according to claim 15, characterized in that the intermediate layer (L_2) comprises a body made around said pillars, configured to be electrically insulating.

17. Electrical impedance measurement system through a biological object comprising a microfluidic component and a potentiostat, characterized in that the microfluidic component is as defined in any one of claims 1 to 16 and in that each electrode is connected to said potentiostat to be brought to an electrical potential.

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