In vivo fluid collection capsule and fluid collection system

Abstract

The present application relates to an in vivo liquid collection capsule, which includes a shell, and an electrowetting control module, a liquid inlet cavity, and a liquid storage cavity housed in the shell. The liquid inlet cavity is connected to the liquid storage cavity, and the liquid inlet cavity is provided with a liquid inlet tube, which is connected to the shell. The shell is also provided with a coating, which covers the opening of the liquid inlet tube before the in vivo liquid collection capsule reaches the designated position, and dissolves to expose the opening of the liquid inlet tube after the in vivo liquid collection capsule reaches the designated position; the electrowetting control module is arranged corresponding to the liquid inlet cavity, and the electrowetting control module changes the surface tension in the liquid inlet cavity by forming an electric field, thereby driving the liquid entering the liquid inlet cavity from the liquid inlet tube to flow into the liquid storage cavity, and the liquid storage cavity is used to store the liquid to be extracted. The present application improves the controllability and airtightness of the in vivo liquid collection capsule by setting an electrowetting control module to control the liquid collection operation process. The present application also provides a liquid collection system including the aforementioned in vivo liquid collection capsule.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to an in vivo fluid collection capsule and a fluid collection system comprising the in vivo fluid collection capsule. Background Art

[0002] Gastrointestinal diseases are common and frequently occurring. During diagnosis and treatment, it is sometimes necessary to remove gastrointestinal fluid for analysis to facilitate treatment decisions. With the advancement of society, greater automation and patient comfort are becoming increasingly important in the process of collecting fluids. Consequently, the use of capsules for collecting fluids has emerged as an alternative to catheter-based endoscopy and other techniques.

[0003] Existing capsules for in vivo fluid collection, on the one hand, rely on pneumatic control to collect fluid, which is not very sensitive and difficult to control. On the other hand, the capsule relies on a tight closure during excretion, which can be inadequately airtight, leading to the risk of contamination of the collected fluid, which can affect analytical results. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of the present application is to provide an in vivo fluid collection capsule and a fluid collection system comprising the in vivo fluid collection capsule, so as to improve the controllability and airtightness of the in vivo fluid collection capsule.

[0005] In the first aspect, the present application provides an in vivo liquid collection capsule, comprising a shell, and an electrowetting control module, a liquid inlet cavity and a liquid storage cavity housed in the shell; the liquid inlet cavity is connected to the liquid storage cavity, and the liquid inlet cavity is provided with a liquid inlet tube, which is connected to the shell, and the shell is also provided with a coating, which covers the opening of the liquid inlet tube before the in vivo liquid collection capsule reaches the designated position, and dissolves to expose the opening of the liquid inlet tube after the in vivo liquid collection capsule reaches the designated position; the electrowetting control module is arranged corresponding to the liquid inlet cavity, and the electrowetting control module changes the surface tension in the liquid inlet cavity by forming an electric field, thereby driving the liquid entering the liquid inlet cavity from the liquid inlet tube to flow into the liquid storage cavity, and the liquid storage cavity is used to store the liquid to be extracted.

[0006] The in vivo liquid collection capsule of the present application significantly reduces the volume of the liquid collection device by placing the electrowetting control module, liquid inlet cavity, and liquid storage cavity within a housing and then inserting the housing into the subject's body, thereby facilitating liquid collection operations. By connecting the liquid inlet cavity to the liquid storage cavity, it is ensured that the collected liquid can flow into the liquid storage cavity for storage. Furthermore, by providing a liquid inlet tube in communication with the housing within the liquid inlet cavity, in vivo liquid can flow from the subject's body into the liquid inlet cavity through the liquid inlet tube.

[0007] By applying a coating to the shell, the coating can shield the opening of the liquid inlet tube before the in vivo liquid collection capsule reaches the designated location in the subject's body, preventing other liquids from entering the liquid inlet cavity. After the in vivo liquid collection capsule reaches the designated location in the subject's body, the coating dissolves to expose the opening of the liquid inlet tube, allowing the liquid to be extracted to enter the liquid inlet cavity through the liquid inlet tube, thereby achieving targeted liquid collection.

[0008] The in-vivo liquid collection capsule of the present application also employs an electrowetting control module positioned at the corresponding position of the liquid inlet cavity to generate an electric field that modulates the surface tension within the cavity, reducing the contact angle between the liquid and the inner wall of the cavity. This in turn drives the liquid flowing from the liquid inlet tube into the liquid storage cavity for sealed storage. By providing the electrowetting control module, the present application extracts and stores liquid when the electrowetting control module is active and terminates liquid extraction and storage when the electrowetting control module is disconnected, thereby improving the controllability of the liquid collection capsule.

[0009] In one embodiment, the electrowetting control module includes an upper electrode plate and a lower electrode plate, and a dielectric layer located between the upper electrode plate and the lower electrode plate; the upper electrode plate is located on the side of the liquid inlet chamber away from the liquid storage chamber, and the lower electrode plate is located on the side of the liquid inlet chamber close to the liquid storage chamber. The dielectric layer is used to achieve insulation between the upper electrode plate and the lower electrode plate, and the upper electrode plate and the lower electrode plate are used to form an electric field in the liquid inlet chamber.

[0010] In this embodiment, upper and lower plates are installed in the electrowetting control module to form an electric field and generate Maxwell stress. Under the action of Maxwell stress, the surface tension balance between the liquid in the liquid inlet chamber and the upper and lower plates is disrupted, thereby changing the contact angle between the liquid and the upper and lower plates, causing the liquid's shape to change.

[0011] By positioning the upper electrode plate on the side of the liquid inlet chamber away from the liquid storage chamber and the lower electrode plate on the side of the liquid inlet chamber closer to the liquid storage chamber, the surface tension between the liquid in the liquid inlet chamber and the lower electrode plate changes, allowing the liquid to enter the liquid storage chamber connected to the liquid inlet chamber. Furthermore, a dielectric layer is provided between the upper and lower electrodes to provide insulation between the upper and lower electrodes, forming an electrowetting system and preventing the liquid in the liquid inlet chamber from being ionized when the electrowetting control module is turned on, thereby improving the reliability of liquid extraction.

[0012] In one embodiment, the electrowetting control module further includes a control unit and a wire. The control unit is located on the side of the upper plate away from the liquid inlet chamber. The control unit is electrically connected to the upper plate and the lower plate through the wire to form an electric field.

[0013] In this embodiment, a control unit is provided on the side of the upper plate facing away from the liquid inlet chamber to control the on / off circuit of the electrowetting control module, thereby achieving controllable liquid extraction. Wires connect the upper plate, the control unit, and the lower plate in sequence, forming an electrical path and an electric field between the upper and lower plates.

[0014] In one embodiment, the control unit comprises a power supply for providing voltage to the control circuit.

[0015] In this embodiment, the control unit is configured to include a power supply, so that the power supply can provide a voltage of 6V to 36V to form an electric field between the upper and lower plates.

[0016] In one embodiment, the control unit includes a radio frequency receiving module for receiving signals.

[0017] In this embodiment, the control unit is configured to include a radio frequency receiving module, so that the control unit performs corresponding control operations through signals received by the radio frequency receiving module.

[0018] In one embodiment, the conductive wire includes a connector, which is located between the upper electrode plate and the lower electrode plate and is used to connect and fix the conductive wire to the lower electrode plate.

[0019] In this embodiment, by providing a wire including a connector located between the upper plate and the lower plate, the control unit can be connected to the lower plate through the wire and the connector, and the connector can also fix the wire, thereby improving the reliability of the control circuit.

[0020] In one embodiment, the dielectric layer is attached to the bottom plate.

[0021] In this embodiment, a dielectric layer is placed in contact with the lower plate, insulating the liquid in the liquid inlet chamber from the lower plate, thereby forming an electrowetting system. Furthermore, by making the dielectric layer hydrophobic, the surface resistance of liquid drive can be reduced, contact angle hysteresis can be minimized, and a smooth and stable droplet flow can be ensured as it enters the liquid reservoir.

[0022] In one embodiment, a protective layer is provided on the outer wall of the liquid inlet cavity, and the protective layer is used to seal the liquid inlet cavity and fix the control unit.

[0023] In this embodiment, a protective layer is provided on the outer wall of the liquid inlet chamber to seal the chamber, preventing liquid from entering other areas and damaging components such as the control unit. The protective layer also serves to secure the control unit, thereby improving the reliability of the in vivo liquid collection capsule.

[0024] In one embodiment, the in vivo liquid collection capsule provided in the present application further includes a plurality of infusion capillaries, each of which is connected between the liquid inlet cavity and the liquid storage cavity, and the liquid in the liquid inlet cavity flows into the liquid storage cavity through each infusion capillary.

[0025] In this embodiment, multiple infusion capillaries connecting the liquid inlet and liquid storage chambers are provided. This allows liquid in the liquid inlet chamber to flow into the liquid storage chamber. Furthermore, the use of smaller diameter capillaries reduces the overall size of the in vivo fluid collection capsule, minimizing discomfort for the patient and facilitating fluid collection. Furthermore, the structure of the infusion capillaries facilitates unidirectional flow of liquid toward the liquid storage chamber.

[0026] In one embodiment, the inner wall of each infusion capillary tube includes a hydrophobic section and a hydrophilic section, and the hydrophilic section is located between the hydrophobic section and the liquid storage cavity.

[0027] In this embodiment, the inner wall of the infusion capillary is configured with a hydrophobic section and a hydrophilic section, with the hydrophilic section positioned between the hydrophobic section and the liquid reservoir. This allows liquid delivered to the hydrophilic section to flow rapidly into the reservoir. Furthermore, when the electrowetting control module is disconnected, the hydrophobic section of the infusion capillary repels liquid, forcing it to flow out of the hydrophobic section. This creates an air gap in the hydrophobic section, which reliably seals and preserves the liquid within the reservoir.

[0028] In one embodiment, a chamfer is provided at the opening of the infusion capillary tube connected to the liquid inlet cavity, so as to reduce the required voltage and promote the liquid in the liquid inlet cavity to flow into the infusion capillary tube.

[0029] In this embodiment, the chamfer provided at the opening where the infusion capillary is connected to the liquid inlet cavity can, on the one hand, reduce the voltage required to be provided by the power supply; on the other hand, it can guide the liquid in the liquid inlet cavity, so that the liquid in the liquid inlet cavity can flow more easily into the infusion capillary.

[0030] In one embodiment, the chamfer may be rounded or have other shapes with a certain angle, so that the energy barrier that the liquid needs to overcome to enter the infusion capillary is reduced, thereby facilitating the liquid to flow into the infusion capillary.

[0031] In one embodiment, the liquid inlet pipe includes a plurality of liquid inlet capillaries, and the wide-diameter ends of the liquid inlet capillaries face the outside of the shell.

[0032] In this embodiment, by configuring the liquid inlet tube as a capillary tube, the overall volume of the liquid collection capsule is reduced, thereby reducing discomfort for the subject. Furthermore, the wide-bore end of the capillary tube is positioned toward the exterior of the housing. This allows the subject's body fluid to flow through the wide-bore end of the capillary tube into the liquid inlet cavity under the action of Laplace pressure. Furthermore, the narrow-bore end of the capillary tube limits the flow of fluid from the subject's body, preventing excessive fluid from entering the inlet cavity, which could lead to excessive pressure within the cavity and damage the air space formed in the hydrophobic section, thereby compromising the sealing effect on the liquid within the liquid storage cavity.

[0033] In a second aspect, the present application also provides a liquid collection system, comprising a wireless controller and an in vivo liquid collection capsule as provided in any of the above embodiments, wherein the wireless controller is used to send instructions from outside the body to the electrowetting control module of the in vivo liquid collection capsule to control the in vivo liquid collection capsule to form an electric field.

[0034] The liquid collection system of the present application utilizes the in vivo liquid collection capsule of the present application in conjunction with a wireless controller, and the wireless controller sends instructions from outside the body to the electrowetting control module to control the liquid collection operation of the in vivo liquid collection capsule. It can be understood that the liquid collection system provided by the second aspect of the present application, because it utilizes the in vivo liquid collection capsule provided by the first aspect of the present application, has a high degree of controllability and good sealing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a working diagram of the liquid extraction system for this application;

[0036] Figure 2 This is a schematic diagram of the cross-sectional structure of an in vivo fluid collection capsule in one embodiment of the present application;

[0037] Figure 3 for Figure 2 A schematic cross-sectional view of an embodiment of a CEC wetting control module;

[0038] Figure 4 for Figure 2 A schematic cross-sectional view of the through hole for connecting the liquid inlet cavity and the liquid storage cavity;

[0039] Figure 5 is a schematic diagram of the cross-sectional structure of an embodiment of an infusion capillary tube;

[0040] Figure 6 is a schematic diagram of the cross-sectional structure of another embodiment of an infusion capillary tube;

[0041] Figure 7 Schematic diagram of the cross-sectional structure of the liquid inlet pipe. DETAILED DESCRIPTION

[0042] To facilitate understanding of the present application, a more comprehensive description of the present application will be provided below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present application.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0044] The specific structure and working process of the in vivo liquid extraction capsule of the present application are described in detail below with reference to the accompanying drawings.

[0045] See also Figure 1 The working diagram of the liquid extraction system 200 of the present application is shown.

[0046] like Figure 1 As shown, the liquid collection system 200 provided by the present application includes a wireless controller 201 and an in vivo liquid collection capsule 100, wherein the in vivo liquid collection capsule 100 can enter the human body, and the wireless controller 201 is located outside the human body. The in vivo liquid collection capsule 100 and the wireless controller 201 are connected wirelessly. The in vivo liquid collection capsule 100 can be used to extract gastrointestinal fluid from the human body. After the liquid collection operation is completed, the in vivo liquid collection capsule 100 can be discharged from the body through the digestive system. By analyzing the liquid extracted by the liquid collection system 200 of the present application, the patient's diagnosis and treatment plan can be determined.

[0047] The internal fluid collection capsule 100 enters the human stomach through the esophagus. In one embodiment, B-mode ultrasound can be used to monitor whether the internal fluid collection capsule 100 has reached the stomach. Furthermore, in this embodiment, the internal fluid collection capsule 100 is equipped with a signal receiving unit, such as a radio frequency receiving module (not shown), which can receive signals sent from the wireless controller 201 outside the human body.

[0048] It is understandable that the liquid collection system 200 of the present application can be used to collect liquid at different locations in the body, typically in the digestive tract. It should be noted that the liquid collection system 200 can be used to extract trace amounts of liquid from living or non-living bodies.

[0049] See also Figure 2 A schematic cross-sectional view of the structure of the in vivo fluid collection capsule 100 provided in one embodiment of the present application.

[0050] like Figure 2As shown, the in vivo liquid collection capsule 100 provided by the present application includes a shell 10, and an electrowetting control module 20, a liquid inlet cavity 30, and a liquid storage cavity 40 housed in the shell 10. At the same time, a liquid inlet pipe 31 is provided on one side wall of the liquid inlet cavity 30, and the liquid inlet pipe 31 is connected to the shell 10. The shell 10 is also provided with a coating 11. It should be noted that the coating 11 covers the opening of the liquid inlet pipe 31 before the in vivo liquid collection capsule 100 reaches the designated position in the subject's body to prevent other liquids from entering the liquid inlet cavity 30, thereby affecting the composition of the extracted liquid and causing diagnostic and treatment errors. After the in vivo liquid collection capsule 100 reaches the designated position, the coating 11 dissolves to expose the opening of the liquid inlet pipe 31, so that the liquid to be extracted enters the liquid inlet cavity 30. Due to this setting, liquid collection only begins after the coating 11 dissolves when the in vivo liquid collection capsule 100 enters the designated position in the subject's body, thereby achieving directional liquid collection.

[0051] It can be understood that after the in vivo liquid collection capsule 100 of the present application enters the body of the subject and is in a liquid environment but no liquid is collected, the pressure inside the in vivo liquid collection capsule 100 is lower than the liquid environment pressure. When the coating 11 dissolves, under the action of Laplace pressure, the liquid can flow from the subject's body into the liquid inlet cavity 30 through the liquid inlet tube 31.

[0052] On the one hand, the material of the coating 11 of the present application can be tailored to the specific environment of the liquid to be extracted. For example, when extracting liquid from the subject's stomach, the coating 11 can be configured as an acidic film coating. After the liquid extraction capsule 100 enters the stomach, the coating 11 dissolves under the action of the acidic gastric fluid, exposing the liquid inlet tube 31. Gastric fluid then flows into the liquid inlet cavity 30 through the liquid inlet tube 31 under the action of Laplace pressure. On the other hand, the coating 11 can be provided only at the opening of the liquid inlet tube 31, or it can be provided to cover the entire shell 10.

[0053] At the same time, the liquid inlet cavity 30 is communicated with the liquid storage cavity 40 to ensure that the liquid entering the liquid inlet cavity 30 from the subject's body can flow into the liquid storage cavity 40 for storage.

[0054] In this embodiment, the electrowetting control module 20 is positioned corresponding to the liquid inlet chamber 30. The electrowetting control module 20 generates an electric field at a corresponding position in the liquid inlet chamber 30, thereby changing the surface tension between the liquid in the liquid inlet chamber 30 and the inner wall of the liquid inlet chamber 30. This reduces the contact angle between the liquid and the inner wall of the liquid inlet chamber 30, thereby driving the liquid entering the liquid inlet chamber 30 through the liquid inlet tube 31 into the liquid storage chamber 40, which is used to store the liquid to be extracted.

[0055] In another embodiment, a portion of the structure of the electrowetting control module 20 and the housing 10 together form the liquid inlet cavity 30 , and the electrowetting control module 20 can also form an electric field in the liquid inlet cavity 30 to achieve the same effect.

[0056] It can be understood that by setting up the electrowetting control module 20, when the electrowetting control module 20 is connected, the in vivo liquid collection capsule 100 extracts and stores liquid based on the action of the electric field; when the electrowetting control module 20 is disconnected, the action of the electric field disappears and the extraction and storage of the liquid is terminated, thereby improving the sensitivity and controllability of the in vivo liquid collection capsule 100.

[0057] See also Figure 3 FIG. 1 is a schematic diagram of the cross-sectional structure of an electrowetting control module 20 in one embodiment of the present application.

[0058] like Figure 3 As shown, in one embodiment, the electrowetting control module 20 includes an upper plate 21, a lower plate 22, and a dielectric layer 23. The upper plate 21 is located on the side of the liquid inlet chamber 30 away from the liquid storage chamber 40, the lower plate 22 is located on the side of the liquid inlet chamber 30 close to the liquid storage chamber 40, and the dielectric layer 23 is located between the upper plate 21 and the lower plate 22. The upper plate 21 and the lower plate 22 form an electric field at the position corresponding to the liquid inlet chamber 30, and generate Maxwell stress, thereby breaking the equilibrium state of the surface tension between the liquid in the liquid inlet chamber 30 and the upper plate 21 and the lower plate 22, causing the shape of the liquid to change.

[0059] At the same time, based on the connection between the liquid inlet chamber 30 and the liquid storage chamber 40, after the equilibrium state of the surface tension between the liquid in the liquid inlet chamber 30 and the lower electrode plate 22 changes, the contact angle between the liquid in the liquid inlet chamber 30 and the lower electrode plate 22 decreases, and the liquid is able to enter the liquid storage chamber 40 under the action of Maxwell stress.

[0060] A dielectric layer 23 is provided between the upper electrode plate 21 and the lower electrode plate 22 to achieve insulation between the upper electrode plate 21 and the lower electrode plate 22, thereby preventing the liquid in the liquid inlet chamber 30 from being ionized when the electrowetting control module 20 is turned on, preventing the extracted liquid composition from changing, and improving the reliability of liquid extraction.

[0061] In one embodiment, a dielectric layer 23 is provided to adhere to the lower electrode plate 22 , that is, the dielectric layer 23 covers the side of the lower electrode plate 22 away from the liquid storage chamber 40 , so that the liquid in the liquid inlet chamber 30 is insulated from the lower electrode plate 22 to form an electrowetting system.

[0062] In one embodiment, the dielectric layer 23 is configured to be hydrophobic, which can reduce the surface resistance of liquid driving, reduce the contact angle hysteresis phenomenon, and ensure that the droplet is smooth and stable when entering the liquid storage chamber 40.

[0063] It is understood that in this embodiment, the material of the dielectric layer 23 can be a polydimethylsiloxane (PDMS) film. In other embodiments, the material of the dielectric layer is not limited to the PDMS film, but can also be any other dielectric film, including but not limited to the PDMS film.

[0064] exist Figure 3 In one illustrated embodiment, the electrowetting control module 20 further includes a control unit 24 and a conductor 25. The control unit 24 is located on the side of the upper plate 21 facing away from the liquid inlet chamber 30 and is used to control the on / off state of the electrowetting control module 20, thereby achieving controllable liquid extraction. The control unit 24 also connects the upper plate 21 and the lower plate 22 via a conductor 25, forming an electrical path.

[0065] In one embodiment, a power supply (not shown) is provided in the control unit 24 to provide a voltage to form an electric field between the upper plate 21 and the lower plate 22. It is understood that the power supply can be a built-in 6V to 36V fixed power supply, so that the voltage of the control circuit is less than 36V, a human safety voltage. The power supply can be a battery.

[0066] In one embodiment, a radio frequency receiving module (not shown) is provided in the control unit 24 for receiving signals from the external wireless controller 201 , so that the control unit 24 can perform circuit-opening and circuit-breaking control operations based on the signals.

[0067] In one embodiment, the wire 25 is provided with a connector 251, so that the wire 25 and the connector 251 of the control unit 24 are connected to the lower electrode plate 22. At the same time, the connector 251 can be positioned between the liquid inlet chamber 30 and the housing 10, and located on the side of the liquid inlet chamber 30 opposite the liquid inlet tube 31, so as to facilitate the fixing of the wire 25, thereby improving the reliability of the control circuit.

[0068] like Figure 4 As shown, in one embodiment, one or more rows of through holes 231 are provided on the dielectric layer 23 and the lower electrode plate 22, so that the liquid inlet chamber 30 and the liquid storage chamber 40 are connected through the through holes 231. It is understood that the radial cross-section of the through holes 231 can be circular, square, or other shapes. At the same time, the number of through holes 231 can also be specifically set according to needs.

[0069] Please look back Figure 3In one embodiment, a protective layer 32 is provided on the outer wall of the liquid inlet cavity 30 to seal the liquid inlet cavity 30. This arrangement enables the liquid inlet cavity 30 to be sealed by the protective layer 32 except for the liquid inlet tube 31 connected to the liquid environment in the subject's body and the structure connected to the liquid storage cavity 40. In this way, the liquid in the liquid inlet cavity 30 can be prevented from entering other areas and damaging electrical components such as the control unit 24. At the same time, the protective layer 32 can also be used to fix the wire 25 between the control unit 24 and the upper electrode 21 to improve the reliability of the in vivo liquid collection capsule 100. The material of the protective layer 32 can be insulating to prevent the electrowetting control circuit from short-circuiting, thereby affecting the liquid collection operation. For example, it can be prepared using PDMS or epoxy resin.

[0070] It is understood that in other embodiments, the protective layer 32 may be located on the side of the upper electrode plate 21 facing away from the liquid inlet chamber 30, as well as on both sides of the liquid inlet chamber 30 adjacent to the upper electrode plate 21. The protective layer 32 may also extend through the entire cross-section of the housing 10. In other words, the protective layer 32 only needs to ensure that the electrical components within the housing 10 function normally in an environment containing liquid.

[0071] Please look back Figure 2 In one embodiment, the in vivo fluid collection capsule 100 provided herein further includes a plurality of infusion capillaries 50. Each infusion capillary 50 is connected between the liquid inlet cavity 30 and the liquid storage cavity 40. This allows the infusion capillaries 50 to communicate with the liquid inlet cavity 30 and the liquid storage cavity 40, allowing the liquid in the liquid inlet cavity 30 to flow into the liquid storage cavity 40. Furthermore, the relatively small diameter of the infusion capillaries 50 reduces the overall volume of the in vivo fluid collection capsule 100, reducing discomfort for the subject and facilitating fluid collection.

[0072] At the same time, the small size of the in vivo fluid collection capsule 100 can also enter deeper and narrower spaces in the subject's body to perform fluid collection operations, thereby improving the practicality of the in vivo fluid collection capsule 100. Furthermore, because the infusion capillary tube 50 has a large end and a small end, that is, the infusion capillary tube 50 has a variable cross-section in the planar direction, it can facilitate the unidirectional flow of liquid toward the liquid storage chamber 40.

[0073] See also Figure 5 The figure shows a schematic cross-sectional structure diagram of an infusion capillary 50 in one embodiment of the present application.

[0074] like Figure 5 As shown, in one embodiment, the inner wall of each liquid infusion capillary 50 includes a hydrophobic section 51 and a hydrophilic section 52. The hydrophilic section 52 is disposed between the hydrophobic section 51 and the liquid storage chamber 40. When the electrowetting control module 20 is in contact, liquid can be transported from the liquid inlet chamber 30 through the hydrophobic section 51 to the hydrophilic section 52 based on the effect of electrowetting, and the liquid can quickly flow into the liquid storage chamber 40 under the attraction of the hydrophilic section 52.

[0075] When the electrowetting control module 20 is disconnected, the electrowetting effect disappears. At this point, the hydrophobic segment 51 of the infusion capillary 50 repels the liquid, forcing it to flow out of the segment 51, forming an air gap in the area of the segment 51. In other words, the segment 51 is filled with air. Because of the air gap, the liquid at both ends of the segment 51 cannot come into contact with each other, and the liquid inlet chamber 30 and the liquid storage chamber 40 are no longer connected, thus ensuring the reliable and sealed storage of the liquid in the liquid storage chamber 40.

[0076] It is understood that in this embodiment, the hydrophobic section 51 and the hydrophilic section 52 of the infusion capillary 50 can be prepared by injection molding capillaries. In other embodiments, other methods can also be used, such as fluorination of the capillary by reactive ion etching (RIE) or etching by micro-nano processing.

[0077] At the same time, in order to clearly show the structure of the infusion capillary 50, Figure 5 The positions and lengths of the hydrophobic section 51 and the hydrophilic section 52 are merely illustrative and do not represent the actual structure and shape of the infusion capillary tube 50. That is, in other embodiments of the present application, the positions and lengths of the hydrophobic section 51 and the hydrophilic section 52 can be adjusted based on the actual scenario. Alternatively, only the hydrophobic section 51 may be provided, sufficing to simply deliver the liquid in the liquid inlet chamber 30 to the liquid storage chamber 40.

[0078] See also Figure 6 The figure shows a schematic cross-sectional structure diagram of an infusion capillary 50 in another embodiment of the present application.

[0079] like Figure 6 As shown, in one embodiment, a chamfer 53 is provided at the opening of each infusion capillary tube 50 connecting to the liquid inlet cavity 30. That is, the chamfer 53 is provided on the surface of the dielectric layer 23 of the infusion capillary tube 50 facing the liquid inlet cavity 30. On the one hand, the chamfer 53 can reduce the energy barrier that the liquid must overcome when entering the infusion capillary tube 50, thereby reducing the voltage required by the power supply. On the other hand, the chamfer 53 can guide the liquid in the liquid inlet cavity 30 to flow more easily from the liquid inlet cavity 30 into the infusion capillary tube 50.

[0080] It can be understood that the opening of the infusion capillary 50 forms an edge in the dielectric layer 23. The sharper the edge, the more obvious the pinning effect is, and the higher the energy barrier that the liquid needs to cross. In other words, the greater the resistance that the liquid in the liquid inlet cavity 30 needs to overcome to enter the infusion capillary 50, the greater the required electrowetting control voltage. Conversely, the smoother the edge, the more subtle the pinning effect is, and the lower the energy barrier that the liquid needs to cross. In other words, the smaller the resistance that the liquid in the liquid inlet cavity 30 needs to overcome to enter the infusion capillary 50, the smaller the required electrowetting control voltage. The provision of the chamfer 53 can reduce the sharpness of the edge of the opening of the infusion capillary 50, thereby reducing the required electrowetting voltage.

[0081] It should be noted that in other embodiments, it can also be set to a rounded corner or other shape with a certain angle, that is, the rounded corner or other shape at this location can be used as long as the energy barrier for the liquid to enter the infusion capillary 50 on the contact surface of the lower electrode 22 is reduced, which is conducive to the liquid flowing into the infusion capillary 50.

[0082] See also Figure 7 The figure shows a schematic cross-sectional structure diagram of the liquid inlet pipe 31 in one embodiment of the present application.

[0083] like Figure 7 As shown, in one embodiment, the liquid inlet tube 31 includes multiple liquid inlet capillaries 311, which reduces the overall size of the internal fluid collection capsule 100, thereby reducing discomfort for the subject and facilitating fluid collection. Furthermore, the small size of the internal fluid collection capsule 100 allows it to enter deeper and narrower spaces within the subject's body for fluid collection, thereby improving the practicality of the internal fluid collection capsule 100.

[0084] It is understood that before the electrowetting control module 20 begins to function, the pressure within the liquid inlet chamber 30 is lower than the pressure within the subject's body. The liquid inlet capillary 311 is configured to have a variable cross-section in the planar direction, with the wide end facing the outside of the housing 10. On the one hand, under the action of the pressure differential, the liquid within the subject's body can flow from the wide end of the liquid inlet capillary 311 into the liquid inlet chamber 30.

[0085] On the other hand, the narrow-diameter end of the liquid inlet capillary 311 can limit the flow rate of the liquid in the subject's body to avoid excessive liquid entering the liquid inlet cavity 30 when the liquid in the liquid storage cavity 40 is sealed and preserved, causing the pressure in the liquid inlet cavity 30 to be too high and destroying the air segment formed in the hydrophobic segment 51, thereby destroying the sealing preservation effect of the liquid in the liquid storage cavity 40.

[0086] It can be understood that in order to clearly show the structure of the liquid inlet pipe 31, Figure 7 The size and number of the liquid inlet capillaries 311 are merely illustrative and do not represent the actual structure and shape of the liquid inlet capillaries 311 .

[0087] In another embodiment, the internal fluid collection capsule 100 may not be provided with a unit for receiving external signals. In other words, the internal fluid collection capsule 100 does not require the wireless controller 201 to send signals. Instead, a timing module may be provided within the internal fluid collection capsule 100. By calculating the time it takes for the internal fluid collection capsule 100 to enter the human stomach, the timing module can be used to calculate the time it needs to set to activate and deactivate the control unit 24, thereby controlling the liquid collection operation of the internal fluid collection capsule 100 and achieving controllability of the internal fluid collection capsule 100.

[0088] It should be understood that the above-mentioned embodiments can be applied individually or in combination. The above is the preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications are also considered to be within the scope of protection of the present application.

Claims

1. A capsule for extracting fluid from the body, characterized in that: It comprises a shell, and an electrowetting control module, a liquid inlet cavity and a liquid storage cavity accommodated in the shell; The liquid inlet cavity is in communication with the liquid storage cavity, and the liquid inlet cavity is provided with a liquid inlet tube, and the liquid inlet tube is in communication with the shell. The shell is further provided with a coating, and the coating shields the opening of the liquid inlet tube before the in vivo liquid collection capsule reaches a designated position, and dissolves to expose the opening of the liquid inlet tube after the in vivo liquid collection capsule reaches the designated position; The electrowetting control module is disposed corresponding to the liquid inlet cavity. The electrowetting control module generates an electric field to change the surface tension in the liquid inlet cavity, thereby driving the liquid entering the liquid inlet cavity from the liquid inlet pipe to flow into the liquid storage cavity. The liquid storage cavity is used to store the liquid to be extracted. The electrowetting control module includes an upper plate and a lower plate, wherein the upper plate is located on a side of the liquid inlet chamber away from the liquid storage chamber, and the lower plate is located on a side of the liquid inlet chamber close to the liquid storage chamber. The upper plate and the lower plate are used to form an electric field, and a through hole is provided on the lower plate, and the through hole enables the liquid inlet chamber to communicate with the liquid storage chamber. The electrowetting control module also includes a plurality of infusion capillaries, each of which is connected between the liquid inlet cavity and the liquid storage cavity, and the liquid in the liquid inlet cavity flows into the liquid storage cavity through each of the infusion capillaries; the inner wall of each of the infusion capillaries includes a hydrophobic section and a hydrophilic section, and the hydrophilic section is located between the hydrophobic section and the liquid storage cavity.

2. The in vivo fluid collection capsule according to claim 1, characterized in that: The electrowetting control module includes a dielectric layer located between the upper plate and the lower plate; the dielectric layer is used to achieve insulation between the upper plate and the lower plate.

3. The in vivo fluid collection capsule according to claim 2, characterized in that: The electrowetting control module further includes a control unit and a wire. The control unit is located on the side of the upper electrode plate away from the liquid inlet chamber. The control unit is electrically connected to the upper electrode plate and the lower electrode plate through the wire to form an electric field.

4. The in vivo fluid collection capsule according to claim 2, characterized in that: The dielectric layer is adhered to the lower electrode plate, and the dielectric layer is hydrophobic.

5. The in vivo fluid collection capsule according to claim 3, characterized in that: The outer wall of the liquid inlet cavity is provided with a protective layer, and the protective layer is used to seal the liquid inlet cavity and fix the control unit.

6. The in vivo fluid collection capsule according to any one of claims 1 to 5, characterized in that: The opening of the infusion capillary tube connected to the liquid inlet cavity is chamfered to reduce the required voltage and promote the liquid in the liquid inlet cavity to flow into the infusion capillary tube.

7. The in vivo fluid collection capsule according to any one of claims 1 to 5, characterized in that: The liquid inlet pipe includes a plurality of liquid inlet capillaries, and the wide-diameter end of the liquid inlet capillary is directed toward the outside of the shell.

8. A liquid collection system, characterized in that: It comprises a wireless controller and an in vivo fluid collection capsule according to any one of claims 1 to 7, wherein the wireless controller is used to send instructions from outside the body to the electrowetting control module of the in vivo fluid collection capsule to control the in vivo fluid collection capsule to form an electric field.

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