Device and method for drying a probe

Abstract

The invention relates to a device (1) for drying a probe, the device (1) comprising a cylindrical well (11), about a central axis (Δ), opening out at an opening (12) such that the probe can be introduced into and removed from the well; the device being such that: - the well is delimited by an internal wall (14) made from a capillary material (15), the capillary material being configured to perform capillary drainage of a liquid; - the capillary material is connected, via a suction channel (19), to a pump (20); - such that when the probe is introduced into the well, while being brought close to the internal wall (14), the capillary material makes it possible to collect, by capillary drainage, a drop of the liquid extending over the surface of the probe, the pump being configured to draw the liquid flowing through the capillary material through the suction channel.

Description

[0001] Device and method for drying a probe

[0002] Description

[0003] TECHNICAL FIELD

[0004] The technical field of the invention is a device for drying a probe, the intended applications being for example the drying of an electrochemical probe.

[0005] EARLIER ART

[0006] Some probes have membranes designed to be placed in contact with a sample. This type of probe can be used in the analysis of samples, such as biological, food, or industrial samples. Examples include pH measuring electrodes, electrodes for measuring dissolved oxygen in a liquid, or ion-selective electrodes, such as Na+ electrodes. + K + or Ca 2+ Depending on the application, the membrane can be made of glass, polymer, or solid crystal.

[0007] Handling membrane electrodes can be tricky, especially in automated processes where the same electrode is used for successive analyses of different samples. Between each analysis, the electrode must be washed and dried, or calibrated.

[0008] Drying a membrane electrode is a delicate process, as the membrane is fragile and may require maintaining a thin layer of moisture. Therefore, excessive drying must not be achieved to avoid over-dehydration of the membrane. Drying should be as uniform as possible and carried out quickly, compatible with industrial measurement speeds.

[0009] The invention described below makes it possible to carry out a uniform drying of an electrode, quickly and gently, while allowing sufficient hydration to be maintained on the membrane, without direct contact with an external body.

[0010] DESCRIPTION OF THE INVENTION

[0011] A first object of the invention is a device for drying a probe, the device comprising a cylindrical well, extending around a central axis, opening onto an opening so that the probe can be introduced and removed from the well, through the opening; the device being such that: - the well is delimited by an internal wall, from which extends a capillary material, the capillary material being configured to perform capillary drainage of a liquid;

[0012] - the capillary material is in fluidic contact with a suction channel, the capillary material extending between the suction channel and the well, the suction channel being configured to be connected to a pump;

[0013] - so that when the probe is introduced into the well, by approaching the inner wall, the capillary material allows to collect, by capillary drainage, a drop of the liquid extending on the surface of the probe, the pump being configured to aspirate the liquid flowing through the capillary material through the suction channel.

[0014] According to one possibility, the capillary material forms an extension, extending around the opening, so as to allow capillary drainage of the fluid when the probe is brought close to the extension.

[0015] According to one possibility, the well extends between a bottom and the opening, the bottom being formed of capillary material.

[0016] The device may include several secondary channels, extending between the suction channel and the capillary material, each secondary channel being configured to ensure fluidic contact between the capillary material and the suction channel.

[0017] Depending on one possibility, the system includes:

[0018] - a base, through which the suction channel extends, the base delimiting a hollow cavity, in fluidic contact with the suction channel;

[0019] - a removable capillary module, comprising the capillary material delimiting the well, the capillary module being intended to be inserted into or removed from the hollow cavity.

[0020] According to one possibility, the capillary material is a hydrophilic material.

[0021] In one possibility, the capillary material has microchannels opening onto its inner surface, extending between the inner surface and the suction channel. In another possibility, the device includes a pump connected to the suction channel. The pump can be configured to:

[0022] aspirate the liquid present in the suction channel at a nominal suction rate, when the probe is not inserted into the well; - when the probe is inserted into the well, do not aspirate the liquid present in the suction channel, or aspirate the liquid present in the suction channel at a suction rate lower than the nominal suction rate.

[0023] According to one possibility, the device includes a gripping unit, configured to hold the probe and move the probe so as to insert or remove it from the well.

[0024] A second object of the invention is a method for drying a probe, on the surface of which a liquid is spread, using a device according to the first object of the invention, the suction channel being connected to a pump, the method comprising:

[0025] a) introduction of the probe into the well, through the opening;

[0026] b) placement of the probe close to the inner wall, so as to allow drainage of the liquid through the capillary material;

[0027] c) removal of the probe;

[0028] d) following step c), activation of the pump, so as to aspirate the liquid collected in the capillary material.

[0029] During steps a) to c), drainage is preferably carried out without contact between the probe and the capillary material.

[0030] Preferably, during steps a) to c), the pump is not activated, or is activated at a pumping rate lower than the pumping rate during step d).

[0031] According to one possibility:

[0032] - the probe extends, perpendicularly to a longitudinal axis, along a first diameter; - the well extends along a second diameter;

[0033] - the second diameter is greater, by at least 1 mm, than the first diameter, so as to avoid contact between the probe and the capillary material.

[0034] According to one possibility:

[0035] - the device includes an extension, as previously described;

[0036] - before step a) or after step c), the probe is applied close to the extension, so as to allow capillary drainage of the fluid through the capillary material forming the extension, preferably without contact between the probe and the extension.

[0037] According to one possibility:

[0038] - the device includes a gripping unit, as previously described;

[0039] - the probe is guided by the gripping unit during steps a) to c).

[0040] A third object of the invention is a probe processing system, comprising: - the device according to the first object of the invention, comprising a gripping unit, as previously described;

[0041] - a pump, connected to the suction channel of the device

[0042] - an enclosure configured to expose the probe to a liquid;

[0043] - the gripping unit is configured to hold the probe and move it into the enclosure so that the probe is exposed to the liquid, then into the well of the device, so as to dry the liquid by bringing the probe close to the inner wall, so that the liquid, extending over the surface of the probe, is drained by the capillary material.

[0044] The probe may be, in particular, an electrochemical probe, of the electrode type, for example, an electrode for measuring pH. The invention may be applied to an element other than a probe.

[0045] The invention will be better understood by reading the explanation of the examples of embodiment presented, in the continuation of the description, in connection with the figures listed below.

[0046] FIGURES

[0047] Figures IA and IB represent a device according to a first embodiment of the invention. Figure IB is a cross-sectional view.

[0048] Figures IC and 1D are cross-sectional views illustrating the movement of a probe in the device described in relation to figures IA and IB.

[0049] Figure 2 shows a cross-sectional view showing the device being used with a small diameter probe.

[0050] Figures 3A and 3B schematically illustrate an embodiment in which the device includes a removable capillary module. Figure 3B is a cross-sectional view.

[0051] Figures 4A and 4B represent a device according to a second embodiment of the invention.

[0052] Figure 5 is a capillary module of a device according to the second embodiment of the invention.

[0053] Figure 6 illustrates the main steps in implementing the invention.

[0054] Figure 7 schematically illustrates a probe treatment system implementing a drying device according to the invention.

[0055] PRESENTATION OF SPECIFIC IMPLEMENTATION METHODS

[0056] Figures IA and IB illustrate a first embodiment of a device 1 according to the invention. In this example, the device is designed to receive a probe 2, of the membrane electrode type, in order to dry it. The probe 2 is, for example, a pH probe. The probe is delimited by a peripheral casing 2', for example, made of glass, metal, or organic material. The probe 2 extends around a longitudinal axis Z to one end. The membrane is located at or near the end.

[0057] The probe 2 has been previously washed by exposing it to a liquid, either by soaking or spraying. In the following example, the liquid is water, but not limited to these applications. Water, like most aqueous solutions, has a high surface tension. Some of the liquid remains on the electrode's contours in the form of droplets 3 formed on the peripheral casing. It is necessary to remove as many of these droplets as possible before using the probe by placing it in a sample. This is to avoid diluting the sample, especially when the sample volume is small.

[0058] Drying is a delicate step: excessive drying, or contact with an external object, can damage the probe and compromise measurement accuracy. As previously stated, a certain level of moisture must remain on the membrane. Exposure to a blown gas stream (e.g., air) is therefore unsuitable, as it can lead to excessive drying of certain parts of the membrane. This is especially true if the distribution of droplets on the membrane is not uniform. Furthermore, exposure to a gas stream can cause droplets to disperse into the probe's surroundings, which can lead to a risk of contamination.

[0059] It is also best to avoid exposing the probe to high temperatures, due to the risk of membrane degradation.

[0060] Another constraint is that the probe can be fragile, particularly when the 2' casing is thin and / or made of a shock-sensitive material. Therefore, any friction of the probe against solid surfaces must be limited or avoided.

[0061] Device 1 is designed to dry probe 2, preventing any contact between the probe and a solid surface. The device comprises a base 10, in which a cylindrical well 11 is formed, extending around a central axis A. The central axis is shown in Figure IC. The well opens into an aperture 12, through which probe 2 can be inserted into or removed from the well. Well 11 has a cylindrical geometry, with the base of the cylinder being circular or polygonal. The diameter or longest diagonal of the well can be between 0.7 mm and 2 cm, and is most often equal to 1 cm ± 30%. Probe 2 is connected to a gripping unit 30, allowing probe 2 to be inserted into well 11 through the aperture 12, as well as withdrawn from the well. The gripping unit 30 is preferably a robotic unit, programmed to move the probe with precision.The gripping unit 30 is configured to allow translation of the probe 2 along the central axis A. The well 11 is delimited by an inner wall 14, from which extends a capillary material 15. The capillary material 15 is defined as a material configured to perform capillary drainage of the liquid forming the droplets 3. It may be a porous material, particularly one with open porosity, or a material containing microchannels. The capillary material is preferably hydrophilic. In the example shown, the capillary material is a nylon-type polymer, traversed by microchannels with diameters ranging from 0.1 mm to 1.5 mm, for example, 0.6 mm. The polymer material is, for example, formed by 3D printing. The device relies on the drainage of the droplets 3, formed on the surface of the probe 2, by the capillary material 15, while preventing contact between the probe 2 and the inner wall 14.Avoiding contact between the probe and the inner wall 14 prevents breakage and contamination of the probe. The probe is dried without contact and without exposing it to a gas flow. Furthermore, the probe can be dried at room temperature.

[0062] The device includes a suction channel 19, configured to be connected to a pump 20. The suction channel 19 is in fluidic contact with the capillary material 15. When the pump is activated, under the effect of suction, the liquid drained in the capillary material 15 is aspirated and flows through the suction channel 19, towards the pump 20.

[0063] The suction channel may open onto the capillary material 15, and / or be in fluidic communication with the capillary material 15 by means of secondary channels 18, the latter extending between the capillary material and the suction channel 19.

[0064] Thus, when the probe 2 is introduced into the well 11, by being brought close to the inner wall 14, the capillary material allows to collect, by capillary drainage, the drops of the liquid 3 extending on the surface of the probe, the pump 20 being configured to aspirate the liquid flowing through the capillary material through the suction channel.

[0065] Figures IC and 1D depict the insertion of probe 2 into well 11, with the longitudinal axis of probe Z parallel, and preferably coaxial, to the central axis A of the well. During its insertion into well 11, probe 2 is kept away from the inner wall 14 to avoid direct contact between probe 2 and the inner wall 14. The gap between probe 2 and the inner wall 14 is preferably on the order of 500 µm to a few mm, for example 2 or 3 mm, so that any droplets 3 present on the surface of probe 2 will lick the capillary material 15. By capillary action, the droplets 3 are then drained through the capillary material 15 from the inner wall 14.

[0066] In the example shown, the well 11 extends between a bottom 13 and the opening 12. Preferably, the bottom is formed of the capillary material 15. The bottom 13 can conform to the shape of the casing 2' of the probe 2, so as to be in contact with droplets 3 arranged at the end of the casing 2'. The distance between the bottom 13 and the opening 12 depends on the geometry of the probe.

[0067] Well 11 extends along a diameter <t>greater than the diameter D of probe 2. The diameter <t>is preferably at least 1 mm larger than the diameter D of probe 2.

[0068] Figure 2 represents a configuration in which the gap between the diameter <t>of well 11 and the diameter D of probe 2 is larger. Probe 2 can be translated, in well 11, perpendicular to the central axis A, so as to be sufficiently close to the inner wall 14 so that the droplets 3 touch the capillary material 15 at the bottom 13. Probe 2 can thus be moved along the inner wall 14, while being sufficiently far from it to avoid direct contact.

[0069] The capillary material 15 may contain metal ions, for example Ag 2+ , having an antimicrobial effect.

[0070] Figures 3A and 3B illustrate an advantageous configuration in which the well and the capillary material form a capillary module 17 that is removable from the base 10. In this configuration, a hollow cavity 10' is provided in the base 10. The suction channel 19 is in fluidic communication with the cavity 10', either directly or via a secondary channel 18. The capillary module 17 is formed from the capillary material 15, which delimits the well 11. The capillary module 17 is intended to be inserted into the hollow cavity 10' during the use of the device 1. The capillary module 17 is intended to be removed after the use of the device 1, so that it can be cleaned or replaced. The replacement of the capillary module 17 can be periodic, for example, after a predetermined number of uses.

[0071] Figures 4A and 4B illustrate an embodiment in which the capillary material 15 extends into an extension 16, arranged around the opening 12, so as to allow capillary drainage of the liquid when the probe 2 is brought near the extension. The extension extends to a distance of at least 1 cm, or even at least 2 cm, from the opening 12. The advantage of the extension 16 is that it allows the tip of the probe 2 to be brought near the capillary material 15, either before or after the probe is inserted into the well 11. The probe 2 is then brought near the extension 16 so that a droplet 3 of liquid at its tip is in contact with the capillary material 15. This allows drainage of the droplet 3 through the capillary material 15 to the suction channel 19. Figure 5 shows a removable capillary module 17 comprising such an extension.

[0072] Regardless of the embodiment, the advantage of the invention is to allow rapid and uniform drying of a probe, with a few minutes being sufficient to allow such drying.

[0073] It is preferable that the pump 20 not be activated, or only negligibly so, when the probe 2 is inserted into the well. This prevents the probe 2 from being exposed to an airflow, which could lead to excessive drying or unwanted displacement of the probe 2 within the well 11. Thus, preferably, the pump is only activated when the probe 2 is removed from the well 11. Alternatively, the pump 20 is activated at its nominal flow rate when the probe 2 is inserted into the well 11, and at a flow rate lower than the nominal flow rate when the probe is removed from the well, so that the probe 2's exposure to the airflow is negligible. Figure 6 illustrates the main steps in implementing a device according to the invention for drying a probe.

[0074] - Step 100: introduction of probe 2 into well 11, through opening 12;

[0075] - Step 110: positioning the probe near the inner wall 14, so as to allow drainage of the liquid through the capillary material 15, keeping the probe away from the inner wall to avoid contact between the probe and the capillary material;

[0076] - Step 120: Removal of probe 2;

[0077] - Step 130: activation of pump 20, so as to aspirate the liquid collected in the capillary material 15.

[0078] The process may be preceded or followed by a disposition of probe 2 in the vicinity of extension 16 as described in connection with figures 5A and 5B.

[0079] Figure 7 depicts an analysis system 1', comprising a drying device 1 as previously described. In this example, the drying device has four aligned wells 11, allowing for the simultaneous drying of four probes 2. Each probe 2 is handled by an automated gripping unit 30, enabling automated translational movement of each probe 2 along three axes. The system includes a washing tank 4, in which each probe can be placed for washing by immersion or spraying.

[0080] Following washing, each probe is moved to device 1, so that it can be dried by non-contact capillary drainage.

[0081] Following drying, each probe can be moved to tubes 5 containing calibration solutions and / or to samples 6 arranged on a well plate.

[0082] Although described in connection with an electrochemical measuring probe, the invention can be implemented with an element for which one wishes to have uniform, rapid drying at room temperature, without exposure to a gas flow and without contact with a solid surface.< / t> < / t> < / t>

Claims

DEMANDS 1. Device (1) for drying a probe (2), the device comprising a cylindrical well (11), extending around a central axis (0), opening onto an opening (12) so that the probe can be introduced and removed from the well, through the opening; the device being such that: - the well is delimited by an internal wall (14), from which extends a capillary material (15), the capillary material being configured to perform capillary drainage of a liquid; - the capillary material is in fluidic contact with a suction channel (19), the capillary material extending between the suction channel and the well, the suction channel being configured to be connected to a pump (20); - so that when the probe is introduced into the well, by approaching the inner wall (14), the capillary material allows a drop of the liquid extending over the surface of the probe to be collected by capillary drainage, the pump being configured to draw the liquid flowing through the capillary material through the suction channel 2. Device according to claim 1, wherein the capillary material (15) forms an extension (16), extending around the opening (12), so as to allow capillary drainage of the liquid when the probe is brought near the extension.

3. Device according to any one of the preceding claims, in which the well (11) extends between a bottom (13) and the opening (12), the bottom being formed of the capillary material.

4. Device according to any one of the preceding claims, comprising several secondary channels (18), extending between the suction channel (19) and the capillary material (15), each secondary channel being configured to ensure fluidic contact between the capillary material and the suction channel.

5. A device according to any one of the preceding claims, comprising: - a base (10), through which the suction channel extends, the base delimiting a hollow cavity (10'), in fluidic contact with the suction channel; - a removable capillary module (17), comprising the capillary material delimiting the well, the capillary module being intended to be inserted into the hollow cavity or removed from the hollow cavity.

6. Device according to any one of the preceding claims, wherein the capillary material (15) is a hydrophilic material.

7. Device according to any one of the preceding claims, wherein the capillary material (15) comprises microchannels opening at the level of the inner face, the microchannels extending between the inner face and the suction channel.

8. A device according to any one of the preceding claims, comprising a pump (20) connected to the suction channel (19), and wherein the pump is configured to: - aspirate the liquid present in the suction channel (19) according to a nominal suction flow rate, when the probe is not introduced into the well; - when the probe is introduced into the well, do not aspirate the liquid present in the suction channel (19), or aspirate the liquid present in the suction channel (19) at a suction flow rate lower than the nominal suction flow rate.

9. Device according to any one of the preceding claims, comprising a gripping unit (30), configured to hold the probe and move the probe so as to introduce or remove it from the well.

10. A method for drying a probe, over the surface of which a liquid is spread, using a device according to any one of the preceding claims, the suction channel being connected to a pump, the method comprising: a) introduction of the probe into the well, through the opening; b) placement of the probe close to the inner wall, so as to allow drainage of the liquid through the capillary material; c) removal of the probe; d) following step c), activation of the pump, so as to aspirate the liquid collected in the capillary material.

11. A method according to claim 11, wherein during steps a) to c), drainage is carried out without contact between the probe and the capillary material.

12. A method according to any one of claims 10 or 11, wherein during steps a) to c), the pump is not activated, or is activated at a pumping rate lower than the pumping rate during step d).

13. A method according to any one of claims 10 to 12, wherein: the probe (2) extends, perpendicularly to a longitudinal axis (Z), along a first diameter (D); the well extends along a second diameter the second diameter is greater, by at least 1 mm, than the first diameter, so as to avoid contact between the probe and the capillary material.

14. A method according to any one of claims 10 to 13, wherein: the device is a device according to claim 2; before step a) or after step c), the probe is applied close to the extension, so as to allow capillary drainage of the fluid through the capillary material forming the extension, preferably without contact between the probe and the extension.

15. A method according to any one of claims 10 to 14, wherein the device is a device according to claim 9; the probe is guided by the gripping unit during steps a) to c).

16. Probe processing system (1'), comprising: the device (1) according to claim 9; a pump (20), connected to the suction channel of the device; an enclosure (4), configured to expose the probe to a liquid; the gripping unit (30) being configured to hold the probe and move it into the enclosure, so that the electrode is exposed to the liquid, then into the well (11) of the device, so as to dry the liquid by bringing the probe close to the inner wall, so that the liquid, extending over the surface of the probe, is drained by the capillary material.

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