Cell-encapsulated oxygen generation device and its application

Abstract

This invention proposes a cell-encapsulated oxygen generation device and its application, belonging to the field of implantable medical device technology. The cell-encapsulated oxygen generation device includes: a raw material storage module for storing hydrogen peroxide solution; a diffusion control module disposed between the raw material storage module and the cell encapsulation module, including a catalytic chamber and an isolation structure. The catalytic chamber contains a catalyst for catalyzing the generation of oxygen from hydrogen peroxide molecules; the isolation structure includes a first isolation membrane and a second isolation membrane. The first isolation membrane is located between the raw material storage module and the catalytic chamber, controlling the diffusion of hydrogen peroxide molecules into the catalytic chamber; the second isolation membrane is located between the catalytic chamber and the cell encapsulation module, controlling the diffusion of oxygen into the cell encapsulation module; the cell encapsulation module contains a cell-containing encapsulation matrix for receiving oxygen and supplying oxygen to the cells. This cell-encapsulated oxygen generation device can control the oxygen generation rate and match the oxygen consumption requirements of cells, effectively avoiding the risks of hydrogen peroxide toxicity and catalyst migration, and exhibits excellent biosafety.

Description

Technical Field

[0001] At least one embodiment of the present invention relates to the field of implantable medical device technology, and more particularly to a cell encapsulation oxygen generation device and its application. Background Technology

[0002] Cell transplantation therapy is a promising treatment strategy for diseases such as type 1 diabetes. In clinical applications, encapsulation structures are typically used to isolate the transplanted cells from the host's immune system to reduce the risk of immune rejection and minimize the long-term use of immunosuppressive drugs. However, while achieving immune isolation, encapsulation structures inevitably increase resistance to the transport of substances such as oxygen. Oxygen has low solubility and limited effective diffusion distance in tissues, making it prone to persistent hypoxia within the encapsulation cavity in the early stages of cell transplantation. This can lead to decreased cell viability, functional decline, and even necrosis, thus limiting the long-term efficacy of encapsulated cell therapy.

[0003] To alleviate early hypoxia in transplanted cells, various oxygen delivery strategies have been explored to enhance local oxygen supply, including but not limited to: using highly oxygen-permeable materials and thin-film structures, exogenous oxygen supply or oxygen-carrying materials, and integrating oxygen-generating modules into encapsulation systems. However, these methods generally suffer from insufficient controllability, complex device structures, the need for frequent oxygen source replenishment in some methods, or difficulty in maintaining a stable oxygen flux that matches cellular oxygen consumption over extended periods. Summary of the Invention

[0004] In view of this, the main objective of the present invention is to provide a cell encapsulation oxygen generation device and its application, in order to at least partially solve at least one of the aforementioned technical problems.

[0005] In one aspect of the present invention, a cell encapsulation oxygen generation device is provided, comprising: a raw material storage module, a diffusion control module, and a cell encapsulation module.

[0006] The raw material storage module is used to store hydrogen peroxide solution.

[0007] The diffusion control module is located between the raw material storage module and the cell encapsulation module. The diffusion control module includes a catalytic chamber and an isolation structure.

[0008] The catalytic chamber is suitable for receiving hydrogen peroxide solution diffused from the raw material storage module; the interior of the catalytic chamber is equipped with a catalyst, which is used to catalyze the hydrogen peroxide molecules entering the catalytic chamber to generate oxygen.

[0009] The isolation structure includes a first isolation membrane and a second isolation membrane; the first isolation membrane is disposed between the raw material storage module and the catalytic chamber to control hydrogen peroxide molecules to enter the catalytic chamber by diffusion; the second isolation membrane is disposed between the catalytic chamber and the cell encapsulation module to control the generated oxygen to enter the cell encapsulation module by diffusion.

[0010] The cell encapsulation module contains a cell encapsulation matrix containing cells. The cell encapsulation module is used to receive oxygen diffused by the diffusion control module and to supply oxygen to the cells within the cell encapsulation matrix.

[0011] In another aspect of the present invention, an implantable medical device is provided, which includes the above-described cell encapsulation oxygen generation device.

[0012] The cell-encapsulated oxygen generation device of this invention uses hydrogen peroxide solution as the oxygen supply raw material. Its diffusion flux into the catalytic chamber is controlled by a first isolation membrane, thereby regulating the oxygen generation rate through diffusion parameters. This allows the oxygen consumption of the cell encapsulation matrix to be matched, ensuring a continuous and adaptive oxygen supply to the cells. The catalyst within the catalytic chamber catalyzes the decomposition of hydrogen peroxide molecules, synergizing with the physical barriers of the first and second isolation membranes. This enables hydrogen peroxide molecules to be efficiently converted into oxygen during the diffusion path, reducing the probability of residual hydrogen peroxide leakage and avoiding the risk of catalyst migration. Structurally, this blocks direct contact between hydrogen peroxide and cells, improving the biosafety of the cell-encapsulated oxygen generation device. The cell encapsulation module stably accommodates the cell encapsulation matrix, receiving and transferring oxygen, ensuring a uniform oxygen supply to the cells within the matrix and alleviating the problem of decreased cell activity caused by localized hypoxia.

[0013] The cell encapsulation oxygen generation device of this invention, when used in implantable medical devices, enables precise, safe, and continuous oxygen production and supply, enhancing its clinical application value in cell transplantation therapy. This device effectively addresses hypoxia in the early stages of transplantation after device implantation, stably matching the oxygen consumption needs of encapsulated cells and ensuring cell viability and function. The synergistic design of catalytic decomposition and dual isolation within the device mitigates the toxicity and migration risks of hydrogen peroxide. Furthermore, the device features a modular integrated design, a compact structure, and flexibly adjustable parameters, adapting to the needs of implantable in vivo applications. Each component is adapted to the in vivo physiological environment, providing a reliable oxygen supply guarantee for the long-term efficacy of cell encapsulation transplantation therapy, combining functionality and clinical applicability. Attached Figure Description

[0014] Figure 1 The diagram below is a schematic diagram of the cell encapsulation oxygen generation device provided by the present invention. In this diagram, A is a schematic diagram of the assembled cell encapsulation oxygen generation device; B is a physical image of the cell encapsulation oxygen generation device; and C is a schematic diagram of the structure of the cell encapsulation oxygen generation device.

[0015] Figure 2A schematic diagram of the mass transfer path of the cell encapsulation oxygen generation device provided by the present invention;

[0016] Figure 3 A schematic cross-sectional view of the cell encapsulation oxygen generation device provided by the present invention;

[0017] Figure 4 The graphs show the diffusion performance of hydrogen peroxide in polydimethylsiloxane (PDS) membranes of different thicknesses. A represents the diffusion performance of 30 wt% hydrogen peroxide in PDS membranes of different thicknesses; B represents the daily average diffusion of 30 wt% hydrogen peroxide through PDS membranes of different thicknesses; C represents the daily average diffusion of different concentrations of hydrogen peroxide through a 1 mm thick PDS membrane; and D represents the daily average diffusion of 6 wt% hydrogen peroxide through a 1 mm thick PDS membrane under different catalyst loading conditions.

[0018] Figure 5 A graph showing the change in oxygen partial pressure in the cell-side region of the cell-encapsulated oxygen generation device provided by the present invention over time under simulated physiological conditions.

[0019] Figure 6 The results of cytotoxicity detection of low-dose cell-encapsulated lactate dehydrogenase in the cell-encapsulated oxygen-generating device provided by the present invention;

[0020] Figure 7 The images show hematoxylin-eosin staining micrographs of low-dose cell encapsulation in the cell encapsulation oxygen generation device provided by the present invention. Among them, A is a staining micrograph of the hydrogen peroxide hypoxia control group, B is a staining micrograph of the phosphate buffer hypoxia control group, C is a staining micrograph of the experimental group, and D is a staining micrograph of the phosphate buffer normoxic control group.

[0021] Figure 8 The graph shows the quantitative detection results of cell activity and toxicity of high-dose cell encapsulation using the cell encapsulation oxygen generation device provided by the present invention. In the graph, A represents the result of lactate dehydrogenase cytotoxicity detection, and B represents the result of cell activity detection using the Cell Counting Kit-8 (CCK-8).

[0022] Figure 9 These are hematoxylin-eosin staining micrographs of cells encapsulated with high doses by the cell encapsulation oxygen generation device of the present invention. Among them, A is a staining micrograph of the hydrogen peroxide-deficient control group, B is a staining micrograph of the phosphate buffer-deficient control group, C is a staining micrograph of the experimental group, and D is a staining micrograph of the phosphate buffer-normative control group. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0024] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this invention.

[0025] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0026] It should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. The terms "installed," "connected," and "linked" should be interpreted broadly, for example, they can be fixed connections, detachable connections, or integral connections; they can be mechanical connections or electrical connections; they can be direct connections or indirect connections through an intermediate medium; they can be internal connections between two elements. The terms "parallel," "perpendicular," and "equal" include the described situation and situations similar to the described situation, where the range of similarity is within an acceptable deviation range, which is determined by those skilled in the art taking into account the measurement under discussion and the errors associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] In cell encapsulation and transplantation therapy, the lack of neovascularization in the early stages of transplantation and persistent local hypoxia are major problems restricting cell survival and affecting treatment efficacy. Therefore, various oxygen generation strategies have become a key research focus. Among these strategies, hydrogen peroxide-based peroxide oxygen generation systems have attracted widespread attention due to their high oxygen source density and outstanding oxygen supply potential. However, existing hydrogen peroxide oxygen generation schemes generally face several problems: the decomposition rate of hydrogen peroxide is significantly affected by diffusion processes, catalytic interfaces, and environmental conditions, leading to an early-stage high oxygen flux followed by a decline or fluctuation, which cannot match the oxygen consumption requirements of cells; at the same time, hydrogen peroxide has strong oxidative toxicity to cells, and leakage or incomplete conversion resulting in local residues can directly damage cells; furthermore, how to ensure complete hydrogen peroxide conversion and prevent its penetration into cell cavities while achieving predictable, adjustable, and long-term stable control of the oxygen generation rate remains a technical challenge for the in vivo application of hydrogen peroxide-encapsulated oxygen generation devices.

[0028] Based on this, the present invention proposes a cell encapsulation oxygen production device and its application. Through the synergistic design of raw material storage, diffusion control, and the cell encapsulation module, combined with the functional coupling of diffusion rate limiting, cavity catalysis, and dual isolation, the toxicity risks and oxygen production controllability issues of the hydrogen peroxide oxygen production system are addressed, achieving safe, stable, and controllable oxygen supply in the early stages of cell encapsulation and transplantation. The present invention sets up a raw material storage module to store hydrogen peroxide solution. By placing a diffusion control module between the raw material storage module and the cell encapsulation module, the catalytic cavity and the first and second isolation membranes are integrated into this module. The first isolation membrane controls the diffusion of hydrogen peroxide into the catalytic cavity, achieving precise regulation of the hydrogen peroxide supply flux and controlling the basic oxygen production rate from the source. Relying on the catalyst inside the catalytic cavity, the incoming hydrogen peroxide is efficiently catalytically decomposed into oxygen. The oxygen is then controlled by the second isolation membrane to diffuse to the cell encapsulation module, where it is finally received by the cell encapsulation module containing the cell encapsulation matrix, supplying oxygen to the cells. Through the above-mentioned modular and functional structural design, this invention achieves an organic combination of hydrogen peroxide diffusion rate limiting, in-process catalytic decomposition, directional oxygen delivery, and dual physical isolation. This ensures that the oxygen production rate matches the oxygen consumption requirements of cells, while effectively avoiding the risks of hydrogen peroxide leakage toxicity and catalyst migration, thus meeting the in vivo application requirements of cell encapsulation and transplantation.

[0029] Figure 1 The diagram below is a schematic diagram of the cell encapsulation oxygen generation device provided by the present invention. In the diagram, A is a schematic diagram of the cell encapsulation oxygen generation device after assembly; B is a physical image of the cell encapsulation oxygen generation device; and C is a schematic diagram of the structure of the cell encapsulation oxygen generation device.

[0030] This invention proposes a cell-encapsulated oxygen-generating device, such as... Figure 1 As shown, it includes: a raw material storage module, a diffusion control module, and a cell encapsulation module.

[0031] The raw material storage module is used to store hydrogen peroxide solution.

[0032] The diffusion control module is located between the raw material storage module and the cell encapsulation module. The diffusion control module includes a catalytic chamber and an isolation structure.

[0033] The catalytic chamber is designed to receive hydrogen peroxide molecules diffused from the raw material storage module. Inside the catalytic chamber is a catalyst used to catalyze the hydrogen peroxide molecules entering the catalytic chamber to generate oxygen.

[0034] The isolation structure includes a first isolation membrane and a second isolation membrane; the first isolation membrane is disposed between the raw material storage module and the catalytic chamber to control hydrogen peroxide molecules to enter the catalytic chamber by diffusion; the second isolation membrane is disposed between the catalytic chamber and the cell encapsulation module to control the generated oxygen to enter the cell encapsulation module by diffusion.

[0035] The cell encapsulation module contains a cell encapsulation matrix containing cells. The cell encapsulation module is used to receive oxygen diffused by the diffusion control module and to supply oxygen to the cells within the cell encapsulation matrix.

[0036] According to an embodiment of the present invention, the shape of the raw material storage module can be box-shaped, cylindrical, or other sealed container structure, and its cavity volume can be 0.1~1 mL, which can be adjusted according to the target oxygen supply time; the cavity wall thickness can be 0.5~3 mm.

[0037] The cavity materials of the raw material storage module include, but are not limited to: any one of the following: medical-grade polymer materials, metallic materials, and inorganic materials, as well as their composite materials. Among them, medical-grade polymer materials include polyetheretherketone (PEEK), polyphenylene sulfone / polysulfone / polyethersulfone (PPSU / PSU / PES), polycarbonate (PC), polymethyl methacrylate (PMMA), polypropylene (PP), polyethylene / ultra-high molecular weight polyethylene (PE / UHMWPE), polyethylene terephthalate / polybutylene terephthalate (PET / PBT), polyamide (PA), polyoxymethylene (POM), thermoplastic polyurethane / thermoplastic elastomer (TPU / TPE), and silicone rubber. The following materials are included: polydimethylsiloxane (PDMS), fluorosilicone rubber, and fluorinated polymers such as perfluoroethylene propylene / perfluoroalkoxy resin / ethylene-tetrafluoroethylene copolymer / polyvinylidene fluoride / polytetrafluoroethylene (FEP / PFA / ETFE / PVDF / PTFE), cyclic olefin copolymers / cyclic olefin polymers (COC / COP), and medical-grade photocurable resins; metallic materials include titanium / titanium alloys and 316L stainless steel; inorganic materials include glass and alumina / zirconia ceramics.

[0038] The cavity of the raw material storage module can be prepared by three-dimensional (3D) printing, injection molding and other processes. Its outer surface can be further coated with a barrier / protective coating, such as any one of parylene coating, fluorinated coating, epoxy / polyurethane coating, etc. The raw material storage module can also be encapsulated with an external encapsulation layer to improve structural sealing and biocompatibility. The material of the encapsulation layer can be polydimethylsiloxane (PDMS) or other elastomers, and the thickness of the encapsulation layer can be 0.5~2 mm.

[0039] According to embodiments of the present invention, the cell encapsulation oxygen generation device, through the modular collaborative design of the raw material storage module, diffusion control module and cell encapsulation module, combined with the functional coupling of diffusion rate limiting, cavity catalysis and dual isolation, solves the problems of early hypoxia in cell encapsulation transplantation, long-term toxicity risks of the oxygen generation system and controllability of oxygen generation, and achieves the unity of oxygen supply efficiency, biosafety and clinical adaptability.

[0040] This cell encapsulation oxygen generation device uses hydrogen peroxide solution stored in the raw material storage module as the oxygen source, and places a diffusion control module between the raw material storage module and the cell encapsulation module. The first isolation membrane in the diffusion control module controls the flux of hydrogen peroxide to the catalytic chamber from the source through diffusion rate limiting, allowing the oxygen generation rate to be primarily regulated by diffusion parameters. This enables flexible matching of the dynamic oxygen consumption needs of different types and sizes of cells, effectively avoiding problems such as initial oxygen supply overshoot, later attenuation, or flux fluctuations that are common in traditional oxygen generation schemes. It ensures that before angiogenesis occurs in the early stages of transplantation, the cell encapsulation matrix receives a continuous oxygen supply adapted to its own oxygen consumption, thereby alleviating the problems of decreased cell activity, functional decline, and even necrosis caused by persistent hypoxia.

[0041] The diffusion parameters include: the equivalent length / thickness of the diffusion path of the first isolation membrane, its effective diffusion area, and its equivalent diffusion coefficient; the equivalent length / thickness of the diffusion path of the second isolation membrane, its effective diffusion area, and its equivalent diffusion coefficient; and the hydrogen peroxide concentration difference between the raw material storage module and the catalytic chamber. These parameters collectively constitute the mass transfer control system of the cell-encapsulated oxygen generation device: the equivalent length / thickness of the diffusion path of the first isolation membrane, its effective diffusion area, and its equivalent diffusion coefficient are used to control the supply rate of hydrogen peroxide into the catalytic chamber; the equivalent length / thickness of the diffusion path of the second isolation membrane, its effective diffusion area, and its equivalent diffusion coefficient are used to regulate the transfer efficiency of the generated oxygen to the cell encapsulation area; and the hydrogen peroxide concentration difference between the raw material storage module and the catalytic chamber provides the driving force for the entire diffusion process. By individually or synergistically adjusting these parameters, the oxygen consumption requirements of different cell types and encapsulation scales can be precisely matched, achieving stable, controllable, and adaptable in-situ oxygen supply.

[0042] The catalytic chamber and dual-membrane structure create a synergistic effect of multiple protections and conversions, structurally mitigating the oxidative toxicity of hydrogen peroxide and the risk of catalyst migration. The catalytic chamber is positioned within the hydrogen peroxide diffusion path, and the internal catalyst efficiently decomposes the incoming hydrogen peroxide into oxygen. This allows for relatively complete conversion of hydrogen peroxide during its migration towards the cell side, reducing the probability of residual unreacted hydrogen peroxide leaking into the cell encapsulation module. The dual-membrane design of the isolation structure constructs a double physical protective barrier. The first membrane physically separates the hydrogen peroxide from the catalyst, while the second membrane effectively blocks the catalyst from the cell encapsulation matrix. This allows oxygen to diffuse freely into the cell encapsulation module while preventing catalyst particles from migrating there and causing cell damage. It also blocks the path of hydrogen peroxide directly contacting the cells, improving the biosafety and reliability of the cell encapsulation oxygen generation device.

[0043] As the cell-carrying unit, the cell encapsulation module stably contains the cell-containing encapsulation matrix, creating a suitable microenvironment for cell growth. It also receives oxygen from the diffusion control module and ensures uniform oxygen distribution within the cell encapsulation matrix, guaranteeing the cells' oxygen supply and preventing localized hypoxia. Furthermore, the cell encapsulation oxygen generation device employs a modular integrated design, achieving miniaturization and integration of the overall structure. This allows it to adapt to the in vivo application requirements of implantable medical devices, and the parameters of each module can be flexibly adjusted to suit different cell transplantation scenarios, transplantation sites, and cell oxygen consumption needs, combining functionality and clinical applicability.

[0044] According to an embodiment of the present invention, the working process of the cell encapsulation oxygen generation device includes the following steps 1 to 4.

[0045] Step 1: Oxygen source loading

[0046] Hydrogen peroxide solution is added to the raw material storage module. After filling, the raw material storage module is sealed to form a stable oxygen source with a preset concentration and quantity, providing a material basis for subsequent continuous and stable oxygen production.

[0047] Step 2: Rate-limited diffusion migration

[0048] Driven by the hydrogen peroxide concentration difference between the feedstock storage module and the catalytic chamber, the hydrogen peroxide solution in the feedstock storage module migrates to the diffusion control module, forming a restricted diffusion flux through the first isolation membrane, which can limit the amount of hydrogen peroxide entering the catalytic chamber within a preset range.

[0049] Step 3: Catalytic decomposition to produce oxygen

[0050] Hydrogen peroxide molecules diffuse into the catalytic chamber and undergo a decomposition reaction under the action of the catalyst inside the chamber, producing oxygen and water. The specific reaction equation is as follows: .

[0051] Wherein, H2O2 is hydrogen peroxide, H2O is water, and O2 is oxygen. The amount of oxygen generated and the amount of hydrogen peroxide consumed satisfy the quantitative relationship of the following equation (I).

[0052] (I)

[0053] in, The amount of oxygen produced. The quantitative relationship, which represents the amount of hydrogen peroxide consumed, can be used to predict the scale of oxygen production, thus facilitating the adaptation to the oxygen consumption needs of cells.

[0054] Step 4: Oxygen diffusion and transfer

[0055] The oxygen generated by the catalytic reaction diffuses from the catalytic chamber to the second isolation membrane of the diffusion control module, and then further enters the grooved encapsulation cavity of the cell encapsulation module, providing sufficient oxygen for the cells in the cell encapsulation matrix within the cavity. The catalytic chamber and the cell side are physically isolated by the second isolation membrane, effectively preventing catalyst particles from migrating to the cell side and causing cell damage. The risk of residual hydrogen peroxide on the cell side is mainly reduced by increasing the catalytic conversion rate of hydrogen peroxide. A residual raw material removal layer can also be added as needed to further enhance the biosafety of the cell encapsulation oxygen generation device.

[0056] Figure 2 This is a schematic diagram of the mass transfer path of the cell encapsulation oxygen generation device provided by the present invention.

[0057] like Figure 2As shown, the mass transfer path of the cell encapsulation oxygen generation device runs longitudinally from bottom to top. The specific mass transfer process is as follows: Driven by the hydrogen peroxide concentration difference between the raw material storage module and the catalytic chamber, the hydrogen peroxide solution in the raw material storage module diffuses upwards. It first undergoes controlled rate-limited mass transfer through the first isolation membrane, precisely regulating the hydrogen peroxide flux entering the catalytic chamber region and preventing uncontrolled leakage. The rate-limited diffused hydrogen peroxide enters the catalytic chamber and rapidly decomposes under the action of the catalyst, converting into oxygen and water. The generated oxygen continues to diffuse upwards, passing through the second isolation membrane and finally reaching the upper cell encapsulation module, providing a continuous and stable oxygen supply to the cells in the cell encapsulation matrix. Simultaneously, the double-layer isolation membrane coupled with the intermediate catalytic layer of this invention achieves dual physical isolation between the hydrogen peroxide raw material, the catalyst, and the cell side. It also significantly reduces the risk of residual hydrogen peroxide exposure on the cell side through along-process catalytic conversion, ensuring the biosafety of the device while achieving controllable and stable oxygen supply.

[0058] According to an embodiment of the present invention, the thickness of the first separator is 0.1~2 mm, and the surface area is 50~300 mm². 2 The second separator has a thickness of 0.05~2mm and a surface area of ​​80~400 mm². 2 .

[0059] In some specific embodiments, the thickness of the first separator can be, for example, 0.1 mm, 0.3 mm, 0.5 mm, 0.7 mm, 1 mm, 1.5 mm, 1.7 mm, 2 mm, etc., and the surface area can be, for example, 50 mm². 2 100mm 2 150mm 2 200mm 2 250mm 2 300 mm 2 The thickness of the second separator can be, for example, 0.05mm, 0.1mm, 0.3mm, 0.5mm, 0.7mm, 1mm, 1.5mm, 1.7mm, 2mm, etc., and the surface area can be, for example, 80mm². 2 100mm 2 150mm 2 200mm 2 250mm 2 300mm 2 400mm 2 wait.

[0060] According to embodiments of the present invention, the thickness and surface area of ​​the isolation membrane can regulate mass transfer efficiency and barrier performance, achieving a balance between hydrogen peroxide diffusion rate limiting and effective oxygen transfer: the thickness and surface area of ​​the first isolation membrane determine the hydrogen peroxide transfer flux, preventing excessively rapid hydrogen peroxide solution supply that could lead to subsequent oxygen production fluctuations; the second isolation membrane, with a thinner thickness range and a suitable surface area, can effectively block catalyst migration while reducing oxygen diffusion resistance, ensuring that the generated oxygen is effectively transferred to the cell encapsulation module to meet the cell's oxygen supply needs. The coordinated dimensional parameters of the first and second isolation membranes enable the oxygen production rate to match the cell's oxygen consumption requirements, balancing oxygen supply controllability and transfer efficiency, and improving the overall oxygen supply stability of the cell encapsulation oxygen production device.

[0061] The materials of the first and second separators are independently selected from at least one of polydimethylsiloxane, fluorosilicone rubber, polyurethane, thermoplastic polyurethane, polyether block amide, polyethylene, polypropylene, polytetrafluoroethylene, expanded polytetrafluoroethylene, fluorinated ethylene propylene, perfluoroalkoxyalkane, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polyethersulfone, polysulfone, nylon, polycarbonate, polyacrylonitrile, and cellulose.

[0062] According to embodiments of the present invention, the materials of the first and second isolation membranes both possess good gas permeability and suitable liquid barrier properties, which can respectively meet the diffusion rate limit of hydrogen peroxide and the mass transfer requirements of oxygen transfer; at the same time, the materials of the isolation membranes are adaptable to in vivo application scenarios, have good biocompatibility, no obvious cytotoxicity, can reduce the host immune response, and the materials have certain mechanical strength and formability, which can adapt to the sealing and assembly requirements of cell-encapsulated oxygen generation devices, taking into account both functionality and practicality, and ensuring the long-term stable operation of cell-encapsulated oxygen generation devices in complex in vivo environments.

[0063] Specifically, the first and second separators differ in their location and function, leading to different material selections and structural designs. The first separator, being closer to the raw material storage module and in constant contact with the hydrogen peroxide solution, prioritizes membrane materials or composite structures with stronger oxidation resistance. This ensures rate limiting and stable supply of hydrogen peroxide diffusion, regulating the flux of hydrogen peroxide to the catalytic chamber and laying the foundation for controllable oxygen production rates. The second separator, closer to the cell encapsulation module, needs to balance oxygen transfer and structural protection. Therefore, it prioritizes membrane materials or composite structures with high oxygen transfer capacity and mechanical stability to achieve physical isolation between the catalyst and the cell encapsulation matrix, while simultaneously ensuring efficient diffusion of catalytically generated oxygen to the cell side, meeting the cell's oxygen supply requirements.

[0064] In some specific implementations, the thickness, effective area, and fixing method of the first and second isolation membranes can be designed separately according to their respective functional requirements, and do not need to be consistent. The materials of the first and second isolation membranes can be the same or different according to actual needs, so that the first and second isolation membranes work together to ensure the controllability, safety, and efficiency of oxygen production in the device.

[0065] In some specific embodiments, when using a higher concentration of hydrogen peroxide (e.g., close to 30 wt%), a protective film (e.g., a fluorinated polymer film or other oxidation-resistant protective layer) can be added between the raw material storage module and the first separator membrane to reduce the chemical effect of the high-concentration hydrogen peroxide solution in the raw material storage module on the first separator membrane material and reduce undesirable decomposition. The protective film can be fixed to adjacent structures by sealing without changing the way hydrogen peroxide diffuses into the catalytic chamber. The material of the protective film is preferably any one of perfluoroethylene propylene (FEP), perfluoroalkoxy resin (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), and polytetrafluoroethylene (PTFE), and the thickness is preferably 10~200 μm.

[0066] According to embodiments of the present invention, the initial concentration of the hydrogen peroxide solution is 0.1 wt% to 30 wt%, for example, it can be 0.1 wt%, 1 wt%, 5 wt%, 10 wt%, 20 wt%, 30 wt%, etc. Preferably, it is 10 wt%. This concentration range can cover the oxygen supply requirements of different cell encapsulation scales and transplantation scenarios. By adjusting the initial concentration of the hydrogen peroxide solution, the oxygen production rate can be synergistically controlled with the diffusion membrane parameters and catalyst loading amount. While avoiding the risk of oxidative toxicity caused by leakage of excessively high concentrations (greater than 30 wt%) of hydrogen peroxide, the oxygen supply capacity of the device in the early target period of transplantation is ensured to match the oxygen consumption requirements of the cells. The conversion efficiency η of the hydrogen peroxide solution is preferably 0.8 to 1, more preferably ≥0.95. A higher conversion efficiency (η≥0.95) can ensure that hydrogen peroxide is fully decomposed in the catalytic chamber, reducing the probability of residual hydrogen peroxide on the cell side, further avoiding the risk of oxidative toxicity, improving the biosafety of the device, and ensuring the activity and function of the cells after encapsulation and transplantation.

[0067] According to an embodiment of the present invention, the thickness of the catalytic chamber is 0.1~2 mm, and the volume is 10~800 mm². 3The lateral dimensions can range from 3 to 20 mm. The design of the catalytic chamber size parameters provides a suitable reaction space for the catalytic decomposition of hydrogen peroxide, achieving synergy between catalytic efficiency, oxygen production regulation, and device miniaturization. This ensures sufficient contact area and reaction time between hydrogen peroxide and the catalyst, guaranteeing the effective catalytic decomposition reaction, while also adapting to the overall miniaturized design of cell-encapsulated oxygen production devices to meet the space requirements of implantable applications. Furthermore, this size range can be matched with the initial hydrogen peroxide concentration and the mass transfer parameters of the isolation membrane. By adjusting the chamber volume, the catalyst loading can be controlled, thereby synergistically regulating the oxygen production rate and ensuring that the oxygen production flux matches the oxygen consumption demand of the cells. A reasonable chamber size can also prevent local accumulation of hydrogen peroxide, further reducing the risk of residual leakage and improving the overall operational stability and biosafety of the device.

[0068] In some specific embodiments, the thickness of the catalytic chamber can be 0.1 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, etc., the width can be 3 mm, 5 mm, 7 mm, 10 mm, 15 mm, 17 mm, 20 mm, etc., and the volume can be 10 mm³. 3 50mm 3 100mm 3 200mm 3 500mm 3 600 mm 3 800 mm 3 The catalytic chamber can be a cavity structure formed by a combination of an elastomer cavity, a rigid shell and an elastic seal, or a porous carrier-filled cavity structure loaded with catalyst.

[0069] The catalyst is disposed inside the catalyst chamber in any of the following forms: powder filling, particle filling, porous bulk filling, or immobilized coating, with a packing amount of 0.1~5 g / cm³. 3 The preferred particle size of the catalyst is 1~300 μm.

[0070] The catalyst includes at least one of inorganic catalysts, noble metal supported catalysts, and enzyme catalysts. Specifically, the inorganic catalyst can be selected from any one of manganese dioxide (MnO2), ferric oxide (Fe2O3), cobalt tetroxide (Co3O4), and copper oxide (CuO); the noble metal in the noble metal supported catalyst can be selected from any one of platinum (Pt), palladium (Pd), ruthenium (Ru), and iridium (Ir), and the noble metal is combined with any feasible supported form on any one of carbon materials, alumina, and silica; the enzyme catalyst can be selected from any one of catalase and peroxidase.

[0071] The catalyst can be immobilized in the catalytic chamber on any one or a combination of two or more of the following supports: porous supports, microspheres, gels, or membrane surfaces. The supports can be selected from: porous ceramics, glass / silicone microspheres, carbon materials (activated carbon, carbon cloth, graphene, etc.), porous polymers (polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyethersulfone (PES), polyurethane (PU) sponge, etc.), hydrogel supports, etc.

[0072] According to embodiments of the present invention, the oxygen flux of the cell encapsulation oxygen generation device can be designed and adjusted through diffusion parameters to adapt to differences in oxygen consumption among different cell types, encapsulation sizes, and transplantation environments. This provides adaptive oxygen supply to cells in the early stages of transplantation, ensuring cell viability. The specific adjustment principle, formula derivation, and parameter design are as follows.

[0073] To facilitate understanding of the regulation mechanism of oxygen production flux, this invention derives the diffusion process of the first isolation membrane based on the assumption that the isolation membrane is rate-limited and diffusion is dominant (e.g., it can be approximated as one-dimensional steady-state diffusion), wherein the hydrogen peroxide diffusion flux can be approximated by the following equation (II).

[0074] (II)

[0075] in, Hydrogen peroxide molar flux (mol / (m)) 2 ·s)); The equivalent diffusion coefficient (m) of the first isolation membrane 2 / s), which is related to the material; Hydrogen peroxide concentration (mol / m³) on the storage module side 3 ); The hydrogen peroxide concentration at the inlet of the catalytic region (mol / m 3 Under fully catalytic conditions, the value can approach a lower value; L1 is the equivalent length (m) of the first separator.

[0076] If the effective diffusion area of ​​the first isolation membrane is A1 (m 2 Then the molar flow rate of hydrogen peroxide is... It can be calculated using the following formula: .

[0077] Considering the actual conversion rate of hydrogen peroxide within the catalytic chamber, and introducing the hydrogen peroxide conversion efficiency η (0 ≤ η ≤ 1), the oxygen generation rate is: .

[0078] in η represents the oxygen generation rate (mol / s). The closer η is to 1, the more complete the conversion and the lower the risk of residual unreacted hydrogen peroxide.

[0079] The oxygen transfer capacity of the second separator can be characterized by its material and geometric parameters (e.g., the equivalent diffusion coefficient of the second separator). The equivalent length of the second isolation membrane is L2; ​​the effective diffusion area of ​​the second isolation membrane is A2, etc., and the material used for the second isolation membrane is not required to be the same as that of the first isolation membrane, so that the oxidation resistance and oxygen supply flux can be optimized respectively.

[0080] To meet the oxygen consumption requirements of cells, the design target can be set to meet them within a target time window: .

[0081] in, The total oxygen consumption rate of the encapsulated cells (which can be estimated from the oxygen consumption per unit cell and the number of cells). This is achieved by adjusting diffusion parameters and catalytic activity. and Matching to alleviate hypoxia in the early stages of transplantation.

[0082] In a preferred embodiment, oxygen flux regulation and matching can be achieved through the following parameter combination: first isolation membrane diffusion path length / membrane thickness L1: preferably 0.1~2 mm; first isolation membrane effective diffusion area A1: preferably 80~300 mm²; first isolation membrane material and microstructure (affecting D) 1,eff ): Such as the type, thickness, and degree of cross-linking of the first separator material; catalytic chamber parameters: chamber volume, catalyst filling amount / fixation method, effective catalytic area and catalytic activity (affecting η and C). r Maintenance level); oxygen transfer parameters of the second separator (affecting D) 2,eff (L2, A2); initial concentration and quantity of hydrogen peroxide: the preferred concentration is 1~30wt%, to cover different oxygen supply durations and safety requirements.

[0083] By designing the above structure and diffusion parameters, an efficient match between oxygen production flux and cellular oxygen consumption demand can be achieved, minimizing the risk of residual hydrogen peroxide while improving cell survival rate in the early stages of transplantation and subsequent functional maintenance.

[0084] According to embodiments of the present invention, the cell encapsulation matrix is ​​a hydrogel encapsulating cells; the hydrogel includes at least one of the following: alginate hydrogel, agarose hydrogel, polyethylene glycol diacrylate hydrogel, polyethylene glycol hydrogel, methacrylamide gelatin, hyaluronic acid hydrogel, fibrin hydrogel, chitosan hydrogel, dextran hydrogel, polyvinyl alcohol hydrogel, and Prönkel hydrogel. The above-mentioned hydrogels exhibit good biocompatibility and cell affinity, have no significant cytotoxicity, and can achieve uniform encapsulation and gentle fixation of cells, ensuring cell viability and function. Multiple hydrogel types can flexibly adapt to the growth requirements of different transplanted cells and suit the physiological environment of in vivo transplantation.

[0085] In some specific embodiments, porous scaffolds, such as porous sponges or microspheres, can also be introduced into the hydrogel to improve the mechanical stability and mass transfer performance of the cell encapsulation matrix.

[0086] According to an embodiment of the present invention, the cell encapsulation module includes a grooved encapsulation cavity for containing the cell encapsulation matrix. The grooved structure can physically limit and fix the cell encapsulation matrix, preventing the cell encapsulation matrix from shifting or scattering in vivo, and ensuring the stability of the cell microenvironment after transplantation.

[0087] The groove depth of the recessed encapsulation cavity is 0.5~10mm, and the effective volume is 50~2000μL. The dimensional parameters of this recessed encapsulation cavity can be adapted to the loading requirements of different cell encapsulation matrices, providing uniform and sufficient oxygen supply for the encapsulated cells.

[0088] According to an embodiment of the present invention, one end of the recessed encapsulation cavity is provided with an opening, and a sealing film is also provided at the opening for sealing the recessed encapsulation cavity. The sealing film is a semi-permeable membrane with a pore size of 50-500 nm and a thickness of 10-200 μm. The pore size of the semi-permeable membrane of 50-500 nm can effectively prevent host immune cells, large molecular proteins, etc. from entering the recessed encapsulation cavity and forming immune rejection, while allowing oxygen, nutrients, and cell metabolites to pass freely, ensuring the material exchange needs of the encapsulated cells and balancing immune isolation and mass transfer efficiency. The thickness of the sealing film of 10-200 μm can reduce oxygen mass transfer resistance while ensuring structural strength, so as to achieve smooth oxygen delivery.

[0089] Semi-permeable membranes are made of at least one of the following materials: polytetrafluoroethylene (PTFE), expanded PTFE, polyethersulfone (PES), polyvinylidene fluoride (PVDF), polyacrylonitrile (PAF), polycarbonate, nylon, cellulose, and polyurethane. These materials possess excellent biocompatibility, chemical stability, and mechanical properties. They are resistant to corrosion from the in vivo physiological environment, non-cytotoxic, and adaptable to various sealing and fixation methods. They enable reliable connection between the sealing membrane and the recessed encapsulation cavity, effectively sealing the cavity, preventing cell encapsulation matrix from scattering or shifting, and blocking external impurities from entering, thus ensuring the stability of the cellular microenvironment. The sealing membrane can be fixed using methods such as compression sealing rings, medical-grade adhesive sealing, thermoforming / thermal welding, ultrasonic welding, or mechanical locking structures.

[0090] Specifically, the materials used for sealing film bonding / sealing include, but are not limited to, any one of the following: medical-grade silicone adhesive, medical-grade epoxy, ultraviolet (UV) curable acrylic adhesive, polyurethane adhesive, hot melt adhesive, or solvent welding system (which must meet biocompatibility and oxidation resistance requirements).

[0091] According to an embodiment of the present invention, the cell encapsulation oxygen generation device further includes at least one of the following: a gas buffer structure, a liquid supply interface, and a residual raw material removal layer, which further optimizes the working stability and practicality of the cell encapsulation oxygen generation device.

[0092] A gas buffer structure is disposed between the second isolation membrane and the cell encapsulation module or embedded in the second isolation membrane to buffer gas pressure fluctuations during the process of hydrogen peroxide molecules generating oxygen.

[0093] According to embodiments of the present invention, the gas buffer structure can be achieved by setting at least one of a gas buffer space, a controlled pressure release structure, or a pressure-bearing structure, thereby completing the temporary storage and uniform release of oxygen, reducing the risk of pressure fluctuations, second membrane bulging, or flux fluctuations caused by local gas accumulation between the second isolation membrane and the cell encapsulation module. The gas buffer structure does not change the basic mechanisms of hydrogen peroxide rate-limiting diffusion, cavity catalytic oxygen production, and oxygen diffusion and transfer.

[0094] For example, to alleviate pressure fluctuations and structural deformation caused by gas accumulation during oxygen production, a stainless steel mesh can be embedded in the second isolation membrane near the cell side to enhance mechanical support and slow down local expansion and deformation; an oxygen buffer chamber or flexible buffer structure can also be set up to achieve temporary storage, uniform distribution and controlled release of oxygen.

[0095] The liquid replenishment interface, located on the raw material storage module, is configured as a disposable sealed interface or a reusable replenishment interface, used to fill or replenish hydrogen peroxide solution into the raw material storage module to ensure continuous oxygen supply to the cell encapsulation oxygen generation device.

[0096] In some specific embodiments, the inner diameter of the liquid inlet can be 0.3~3 mm, and the outer diameter can be 0.8~6 mm; the sealing method can be a one-time curing seal, or it can be repeatedly replenished through a self-sealing injection port (rubber stopper / silicone stopper), thereby extending the oxygen supply time of the device, reducing the overall replacement frequency, and improving the convenience of clinical use.

[0097] A residual material removal layer, disposed between the second isolation membrane and the cell encapsulation module, is used to capture and decompose residual unreacted hydrogen peroxide molecules, further enhancing the biosafety of the cell encapsulation oxygen generation device. For example, this residual material removal layer can be configured as an immobilized removal component layer or a replaceable removal sheet.

[0098] In some specific embodiments, the thickness of the residual raw material removal layer can be 0.05~2 mm, and it can be any one of the immobilized catalyst layer, replaceable sheet layer, or porous filling layer. The materials of the residual raw material removal layer include, but are not limited to: manganese dioxide (MnO2), iron / cobalt (Fe / Co) based metal oxides, platinum / palladium (Pt / Pd) and other noble metal catalysts, immobilized catalase / peroxidase, reducing scavenging materials, or combinations thereof. The residual raw material removal layer can be fixed to the surface of the second isolation membrane or the cavity wall between the second isolation membrane and the cell encapsulation module, or it can be set as an independent module. Different fixation methods can flexibly adapt to the overall structural design of the cell encapsulation oxygen generation device.

[0099] According to embodiments of the present invention, the cell-encapsulated oxygen-generating device can be any of the following shapes: sheet-like, disc-like, or strip-like. This diverse structural design allows for flexible adaptation to the physiological spatial characteristics of different in vivo transplantation sites, facilitating implantation and fixation. The cell-encapsulated oxygen-generating device has a height of 2-20 mm and a lateral dimension of 10-60 mm. This satisfies the functional layout and working space requirements of the raw material storage, diffusion control, and cell encapsulation modules, ensuring oxygen production and transfer efficiency, while avoiding tissue damage due to excessive size, thus balancing functionality and clinical applicability.

[0100] Figure 3 This is a cross-sectional structural diagram of the cell encapsulation oxygen generation device provided by the present invention.

[0101] According to embodiments of the present invention, such as Figure 3 As shown, the preparation process of the cell encapsulation oxygen generation device can be carried out step by step according to the module assembly, as detailed below.

[0102] A raw material storage module (3D-printed cavity) fabricated by 3D printing is provided with an outward-extending interface at one end. This interface is connected to a polyurethane tube, which serves as the liquid inlet for the raw material storage module. The module is immersed in polydimethylsiloxane (PDMS). After the PDMS cures, a PDMS shell layer is formed on the outside of the raw material storage module, and simultaneously, a first PDMS diffusion film (i.e., the first isolation film) is formed. Subsequently, a grooved catalytic cavity structure is fabricated using PDMS, and the catalyst is loaded into the catalytic cavity. Then, another PDMS diffusion film (i.e., the second isolation film) is used to seal the catalytic cavity and fix it by adhesive bonding, thereby forming a diffusion control module.

[0103] The prepared raw material storage module was sealed to the diffusion control membrane to ensure good sealing performance, so that hydrogen peroxide molecules in the raw material storage module could only enter the catalytic chamber by diffusion through the first isolation membrane. At the same time, a PDMS groove structure was separately prepared as a groove-type encapsulation cavity for the cell encapsulation module to contain the cell encapsulation matrix (cell encapsulation hydrogel).

[0104] The diffusion control module and the cell encapsulation module are sealed together to ensure that the oxygen generated by catalysis can pass smoothly through the second isolation membrane of the diffusion module and diffuse into the recessed encapsulation cavity of the cell encapsulation module. After the connection is completed, hydrogen peroxide solution is filled into the raw material storage module through the liquid filling port. After filling, the liquid filling port is sealed using PDMS thermosetting to form a one-time sealing structure to prevent hydrogen peroxide solution leakage.

[0105] During operation of the cell-encapsulated oxygen generation device, hydrogen peroxide molecules in the raw material storage module, driven by the hydrogen peroxide concentration difference between the raw material storage module and the catalytic chamber, diffuse in a controlled manner through the first isolation membrane of the diffusion control module into the catalytic chamber. There, under the action of the catalyst, they undergo a decomposition reaction to generate oxygen. The generated oxygen then diffuses through the second isolation membrane of the diffusion module into the cell encapsulation module, providing oxygen for subsequently inserted cells. After the cell-encapsulated oxygen generation device has been running for a period of time and the oxygen generation state has stabilized, the hydrogel containing cells is placed into the groove of the cell encapsulation module. Finally, the opening of the groove is sealed with a sealing film, thus completing the assembly of the entire cell-encapsulated oxygen generation device.

[0106] According to another aspect of the present invention, an implantable medical device is provided, which includes the above-described cell encapsulation oxygen generation device.

[0107] According to embodiments of the present invention, implantable medical devices utilizing the cell-encapsulated oxygen generation device of the present invention can regulate the mass transfer process of hydrogen peroxide through rate-limited diffusion via an isolation membrane, achieving an adaptation between the oxygen generation rate and the oxygen consumption requirements of the encapsulated cells. Combined with a synergistic protective design of catalytic decomposition and dual isolation, this effectively solves the problems of local hypoxia and unstable oxygen supply in the early stages of transplantation that may exist in existing implantable cell therapy devices, improving the survival rate and functional maintenance capacity of cells in the early stages of transplantation, and enhancing clinical treatment efficacy. The dual isolation and catalytic conversion design of the cell-encapsulated oxygen generation device can effectively avoid the leakage toxicity of hydrogen peroxide and the risk of catalyst migration, meeting the in vivo biosafety requirements of implantable devices. Simultaneously, the oxygen generation flux can be flexibly adjusted through the parametric design of the cell-encapsulated oxygen generation device, exhibiting strong adaptability; the modular and compact structure can adapt to the miniaturization requirements of implantable medical devices, enabling long-term stable operation in vivo and providing reliable support for the clinical translation of implantable cell therapy.

[0108] To verify the oxygen supply rate regulation capability, oxygen production stability, biosafety, and cell protection effect of the cell-encapsulated oxygen generation device and the implantable medical device containing it of the present invention, performance tests and in vitro verification experiments were conducted on the cell-encapsulated oxygen generation device provided by the present invention. The specific process and results are as follows.

[0109] (a) Hydrogen peroxide permeation / rate-limited supply characteristic test

[0110] The permeation / rate-limited supply characteristics of hydrogen peroxide were tested to verify the rate-limited diffusion control effect of the separator membrane on hydrogen peroxide. The influence of key parameters such as membrane thickness, initial hydrogen peroxide concentration, and catalyst dosage on hydrogen peroxide diffusion flux was clarified, and a suitable parameter window with "rate-limited supply and controllable leakage" was selected. The specific test process is as follows.

[0111] 1. Preparation of the isolation membrane: Polydimethylsiloxane (PDMS) prepolymer (Sylgard184) and curing agent were mixed at a mass ratio of 10:1 to obtain a casting solution. The casting solution was poured into a horizontally placed 100mm petri dish, and after degassing, it was cured at 60℃ for 1h. PDMS isolation membranes with different film thicknesses L1 (0.5mm, 1mm, 1.5mm) were prepared by controlling the amount of casting solution poured. After curing, the PDMS isolation membrane was cut into circular pieces with the same effective diffusion area A1 for later use.

[0112] 2. Diffusion test system setup: Experimental groups with different membrane thicknesses L1, different initial hydrogen peroxide concentrations, and different catalyst dosages were set up. A dual-chamber diffusion cell (divided into donor and acceptor sides by a PDMS separator membrane) was used to clamp and seal the PDMS separator membrane under test to ensure that the effective diffusion area A1 was constant and there was no bypass leakage. Hydrogen peroxide solution was added to the donor side and deionized water was added to the acceptor side. The temperature was controlled at 37℃ throughout the test, and the hydrogen peroxide solution was kept gently stirred.

[0113] 3. Sampling and Quantitative Detection: Samples were taken from the receptor side at fixed time intervals, and the hydrogen peroxide concentration on the receptor side was determined using the titanium sulfate colorimetric method. Specific procedure: 50 μL of hydrogen peroxide sample was mixed with 50 μL of titanium sulfate working solution (the working solution can be prepared according to a predetermined method). The absorbance was measured at 405 nm using a microplate reader (Tecan Infinite 200Pro), and the hydrogen peroxide concentration was calculated using a standard curve.

[0114] 4. Data processing: Plot the hydrogen peroxide concentration-time curve on the receptor side, calculate the hydrogen peroxide permeation flux and equivalent permeability coefficient, compare the differences in diffusion performance under different parameter conditions, and determine the appropriate parameter window.

[0115] Figure 4 The graphs show the diffusion performance of hydrogen peroxide in polydimethylsiloxane (PDS) membranes of different thicknesses. Specifically, A represents the diffusion performance of 30 wt% hydrogen peroxide in PDS membranes of different thicknesses; B represents the daily average diffusion of 30 wt% hydrogen peroxide through PDS membranes of different thicknesses; C represents the daily average diffusion of different concentrations of hydrogen peroxide through a 1 mm thick PDS membrane; and D represents the daily average diffusion of 6 wt% hydrogen peroxide through a 1 mm thick PDS membrane under different catalyst loading conditions.

[0116] like Figure 4 As shown in Figure A, it can be observed that under the same membrane thickness, the diffusion amount of hydrogen peroxide is basically positively correlated with the test time, indicating that the diffusion process of hydrogen peroxide in the PDMS membrane conforms to the steady-state diffusion law; the test results of Figure B show that under the same hydrogen peroxide concentration, the smaller the PDMS membrane thickness, the greater the daily average diffusion amount of hydrogen peroxide. The daily average diffusion amount of the 0.5 mm thick membrane is about twice that of the 1 mm thick membrane and three times that of the 1.5 mm thick membrane, verifying the regulatory effect of membrane thickness (equivalent length of diffusion path) on hydrogen peroxide flux, providing support for the rate-limited diffusion design of cell encapsulation oxygen generation devices; the test results of Figure C show that under the condition that the PDMS membrane thickness is fixed at 1 mm, the higher the initial concentration of hydrogen peroxide, the greater its daily average diffusion amount, verifying that the hydrogen peroxide concentration difference can act as a diffusion driving force to positively regulate the hydrogen peroxide flux, providing experimental basis for the design of cell encapsulation oxygen generation devices to adapt to different cell oxygen consumption needs by adjusting the hydrogen peroxide concentration; the test results of Figure D show that 6 When wt% hydrogen peroxide passes through a 1 mm thick PDMS membrane, the residual hydrogen peroxide content that permeates through the membrane decreases significantly with increasing catalyst dosage, verifying the catalyst's removal effect on residual hydrogen peroxide and providing support for the structural design of this invention to reduce the risk of hydrogen peroxide toxicity and improve biosafety.

[0117] (II) Testing of oxygen production capacity and stability of cell encapsulation oxygen generation device

[0118] The overall oxygen production performance, oxygen supply adjustability, and long-term stability of the assembled cell-encapsulated oxygen generation device were tested, and the biosafety of the device was verified. The specific testing and verification process is as follows.

[0119] 1. Assembly and pretreatment of cell encapsulation oxygen generation device: Assemble the cell encapsulation oxygen generation device according to the method of this embodiment of the invention, fill the raw material storage module with hydrogen peroxide solution of a preset concentration and complete the sealing.

[0120] 2. Test conditions: The cell-encapsulated oxygen generation device was placed in a sealed test chamber filled with deionized water, and the temperature was controlled at 37°C throughout the test to simulate the physiological environment. Dissolved oxygen sensors (oxygen electrodes, OX-N, Unisense) were placed in the cell-side (cell encapsulation module) region of the device, and the changes in oxygen partial pressure in this region over time were continuously recorded.

[0121] 3. Parameter evaluation: Experimental groups with different diffusion and catalytic parameters were set up, and the steady-state oxygen supply flux, initial oxygen overshoot and subsequent decay trend of the cell-encapsulated oxygen generation device were compared to evaluate the adjustability and stability of the oxygen supply of the cell-encapsulated oxygen generation device.

[0122] 4. Safety Joint Testing: While testing oxygen production performance, the residual concentration of hydrogen peroxide in the cell-side (cell encapsulation module) region is simultaneously detected to verify the effectiveness of the isolation structure (second isolation membrane) and along-process catalytic conversion in reducing the risk of hydrogen peroxide leakage on the cell side.

[0123] Figure 5 The graph shows the change in oxygen partial pressure in the cell-side region of the cell-encapsulated oxygen generation device provided by the present invention over time under simulated physiological conditions.

[0124] like Figure 5 As shown, the cell encapsulation oxygen generation device of the present invention can maintain a stable oxygen supply state within a preset time, without significant initial overshoot or subsequent attenuation, and has the potential to meet the stable oxygen supply requirements of cell encapsulation transplantation applications; at the same time, no obvious hydrogen peroxide residue was detected on the cell side, verifying the biosafety of the cell encapsulation oxygen generation device.

[0125] (III) In vitro validation of low / high dose cell encapsulation

[0126] In a simulated hypoxic environment during the early stages of in vivo transplantation, the survival protection effect of the cell encapsulation oxygen generation device of this invention on cells with different encapsulation doses was verified, clarifying the practical application value of the cell encapsulation oxygen generation device. The specific test process is as follows.

[0127] 1. Cell encapsulation preparation

[0128] Low-dose cell encapsulation preparation: A 0.5% (w / v) calcium sulfate (CaSO4) / ethanol suspension was added dropwise to the recessed encapsulation cavity of the cell encapsulation module in the cell encapsulation oxygen generation device. After CaSO4 was deposited on the surface of the recessed encapsulation cavity, the ethanol was evaporated and removed. Approximately 1.5 × 10⁻⁶ ppm of the solution was then added. 6 Mouse insulinoma cells (MIN6 cells) were premixed with 200 μL of sodium alginate solution and injected into a grooved encapsulation cavity. Calcium chloride (CaCl2) aqueous solution was added dropwise for cross-linking for 5 min. After removing excess liquid from the surface, the grooved encapsulation cavity was immersed in 10 mL of culture medium. The culture medium used was Dalberg modified Eagle medium (DMEM) containing 5.5 mM glucose, supplemented with 10% fetal bovine serum, 1% penicillin-streptomycin, 1% L-glutamine, and 0.001% (v / v) β-mercaptoethanol.

[0129] High-dose cell encapsulation: Approximately 2.1 × 10⁻⁶ cells are encapsulated in 200 μL of hydrogel. 7 The preparation process involved MIN6 cells, with corresponding adjustments to the thickness of the diffusion isolation membrane and the amount of catalyst. The remaining preparation steps were consistent with those for low-dose cell encapsulation.

[0130] 2. Grouping and cultivation conditions

[0131] The experiment consisted of four groups: the experimental group (the raw material storage module was filled with 6 wt% hydrogen peroxide solution, and a catalyst layer was installed in the device, enabling normal catalytic oxygen production), the hydrogen peroxide (H2O2) hypoxia control group (the raw material storage module was filled with 6 wt% hydrogen peroxide solution, and no catalyst layer was installed in the device, resulting in no catalytic oxygen production capacity), the phosphate-buffered saline (PBS) hypoxia control group (the raw material storage module was filled with 1×PBS, and no catalyst layer was installed in the device, resulting in no external oxygen supply capacity), and the PBS normoxic control group (the raw material storage module was filled with 1×PBS, and no catalyst layer was installed in the device, serving as a blank control for normal cell growth). The experimental group, the hydrogen peroxide hypoxia control group, and the PBS hypoxia control group were cultured under hypoxic conditions (1% oxygen (O2), 5% carbon dioxide (CO2)) to simulate the hypoxic environment in vivo during the early stages of transplantation; the PBS normoxic control group was cultured under normal oxygen (21% O2) conditions. The target oxygen partial pressure in the hypoxia incubator was achieved by controlling the flow rate of carbon dioxide / nitrogen (CO2 / N2) gas.

[0132] 4. Detection Indicators and Methods

[0133] Hematoxylin-eosin (H&E) staining: After culturing for 48 h, encapsulated cells from the four groups were removed, fixed with 4% paraformaldehyde, sectioned, and stained with H&E. The integrity of the cell structure was observed under a microscope.

[0134] Lactate dehydrogenase (LDH) cytotoxicity assay: Centrifuge the culture medium after culture, extract the supernatant, and use a lactate dehydrogenase cytotoxicity assay kit for detection; Specific operation: Take 120 μL of supernatant from each well into a 96-well plate, add 60 μL of LDH colorimetric reagent (a mixture of lactate solution, enzyme solution, p-iodonitroxytetrazolium violet (INT) dilution and INT solution (10×) in a volume ratio of 10:10:9:1), incubate at room temperature in the dark for 30 min, and measure the absorbance at a wavelength of 490 nm using a microplate reader, with 600 nm as the reference wavelength for dual-wavelength measurement.

[0135] Cell viability assay using Cell Counting Kit-8 (CCK-8): Prepare a DPBS solution containing 3.4 mg / mL sodium alginate enzyme. Place a hydrogel sheet in a centrifuge tube, add 500 μL of enzyme solution to each sheet, and incubate at 37°C for 15 min until the hydrogel is basically dissolved. After mixing, transfer 100 μL to each well of a 96-well plate, add 10 μL of CCK-8 reagent (Beyotime), and continue incubation for 1 h. Measure the absorbance at 450 nm.

[0136] Figure 6 The results of cytotoxicity detection of low-dose cell-encapsulated lactate dehydrogenase in the cell-encapsulated oxygen-generating device provided by the present invention.

[0137] like Figure 6As shown, in the oxygen-generating experimental group using the cell-encapsulated oxygen-generating device of the present invention, the LDH release was significantly lower than that of the hydrogen peroxide-deficient control group and the phosphate-buffered saline (PBS)-deficient control group, and close to the level of the PBS normoxic control group. This indicates that the oxygen-generating device of the present invention can improve cell damage caused by hypoxia and reduce cytotoxicity by providing stable in-situ oxygen supply, thus exhibiting good cell protection effects.

[0138] Figure 7 These are hematoxylin-eosin staining micrographs of low-dose cell encapsulation in the cell encapsulation oxygen generation device provided by this invention. In the images, A is a staining micrograph of the hydrogen peroxide-deprived control group, B is a staining micrograph of the phosphate buffer-deprived control group, C is a staining micrograph of the experimental group, and D is a staining micrograph of the phosphate buffer-normative control group.

[0139] like Figure 7 As shown, in the cell encapsulation oxygen generation device of the present invention, the cells in the experimental group and the PBS normoxic control group had intact overall structure and normal morphology, while only a small number of cells in the hydrogen peroxide hypoxia control group and the PBS hypoxia control group had intact structure and obvious morphological damage. This verifies that the stable oxygen supply of the cell encapsulation oxygen generation device of the present invention can effectively maintain the integrity of cell structure under hypoxic conditions.

[0140] Figure 8 The graph shows the quantitative detection results of cell activity and toxicity of high-dose cell encapsulation using the cell encapsulation oxygen generation device provided by the present invention. In the graph, A represents the result of lactate dehydrogenase cytotoxicity detection, and B represents the result of cell activity detection using the Cell Counting Kit-8 (CCK-8).

[0141] like Figure 8 As shown, LDH detection results indicated that the LDH release in the experimental group of the cell-encapsulated oxygen-generating device of the present invention was significantly lower than that in the hypoxic control groups and close to the level in the PBS normoxic control group; CCK-8 detection results showed that the absorbance value of the experimental group was significantly higher than that of the control groups, indicating a higher cell viability. Both results jointly validate the stable oxygen supply effect and good cell protection effect of the cell-encapsulated oxygen-generating device of the present invention.

[0142] Figure 9 These are hematoxylin-eosin staining micrographs of cells encapsulated with a high dose of oxygen-generating cells using the cell encapsulation device of the present invention. In the images, A is a staining micrograph of the hydrogen peroxide-deprived control group, B is a staining micrograph of the phosphate buffer-deprived control group, C is a staining micrograph of the experimental group, and D is a staining micrograph of the phosphate buffer-normative control group.

[0143] like Figure 9As shown, the cells in the experimental group of the cell encapsulation oxygen generation device of the present invention and the PBS normoxic control group have intact structures and uniform distribution. The cells in the hydrogen peroxide hypoxia control group and the PBS hypoxia control group have poor cell integrity and obvious damage and structural destruction. This indicates that the cell encapsulation oxygen generation device of the present invention still has good oxygen supply capacity and cell protection effect under high-dose cell encapsulation scenarios.

[0144] In summary, the cell encapsulation oxygen generation device and its application provided by the present invention have at least one or a portion of the following beneficial effects.

[0145] 1. To alleviate early transplantation hypoxia, the oxygen flux of the cell encapsulation oxygen generation device of this invention is dominated by diffusion parameters, which can precisely match the oxygen consumption demand of the cells: a diffusion rate-limiting path is set between the raw material storage module and the catalytic chamber, and the parameters in the path are controlled, including the equivalent length / thickness of the first isolation membrane (L1), the effective diffusion area (A1), and the equivalent diffusion coefficient (D). 1,eff This diffusion rate limiting design controls the flux of hydrogen peroxide (H2O2) into the catalytic chamber. It transforms the hydrogen peroxide supply rate from an uncontrolled leakage mode to one controlled by L1, A1, and D2. 1,eff The determined controllable diffusion flux mode allows for the directional design and stable, repeatable achievement of the hydrogen peroxide molecular molar flow rate entering the catalytic chamber. The oxygen production flux can be flexibly adjusted according to diffusion parameters, thereby enabling the oxygen supply capacity of the cell encapsulation oxygen production device to be designed to be on the same order of magnitude as the total oxygen consumption rate of the cell, fundamentally alleviating the persistent hypoxia problem in the early stages of cell encapsulation transplantation and before angiogenesis.

[0146] 2. Enhancing oxygen supply stability through a coupled design of diffusion rate limiting and catalytic chamber to avoid excessively rapid initial oxygen supply followed by insufficient supply: A first and second isolation membrane are incorporated into the diffusion control membrane module. The first isolation membrane primarily supplies hydrogen peroxide (H2O2) via diffusion, while the second isolation membrane primarily transfers oxygen (O2) via diffusion. The rate-limiting design of the first isolation membrane smooths out flux fluctuations of hydrogen peroxide entering the catalytic chamber, which rapidly converts incoming hydrogen peroxide molecules into oxygen. The second isolation membrane, primarily for oxygen diffusion, uniformly diffuses the oxygen generated within the catalytic chamber to the cell encapsulation module in a slow-release manner. This coupled design ensures that the oxygen supply to the cell encapsulation oxygen generation device is no longer dominated by instantaneous reaction conditions such as local convection and transient fluctuations in hydrogen peroxide concentration. Instead, it is stably regulated by both diffusion flux and catalytic capability, ultimately achieving a smoother oxygen supply curve. This significantly reduces the risk of oxygen supply mismatch caused by initial oxygen overshoot and subsequent oxygen supply attenuation, improving the long-term stability of encapsulated cell function.

[0147] 3. Reducing the risk of hydrogen peroxide oxidation toxicity through rate-limited supply, catalytic consumption, and isolation structure: This invention achieves safety control through a triple protection design. First, physical isolation between hydrogen peroxide and the catalyst: the stored hydrogen peroxide solution does not mix directly with the catalyst, but enters the catalytic chamber in a controlled manner via diffusion. Second, physical isolation between the catalyst and the cell: an isolation structure (such as a second isolation membrane) is set between the catalytic chamber and the cell encapsulation module to prevent catalyst migration into the cell encapsulation module. Third, functional conversion design: the catalytic chamber fully consumes and converts the incoming hydrogen peroxide, ensuring that the medium output to the cell encapsulation module is mainly oxygen, significantly reducing the content of residual unreacted hydrogen peroxide. Simultaneously, rate-limited supply reduces the amount of hydrogen peroxide entering the catalytic chamber per unit time, the catalytic chamber provides sufficient reaction capacity for full conversion, and the isolation structure prevents catalyst migration and maintains structural stability. These three elements work synergistically to maximize the conversion of hydrogen peroxide before it reaches the cell encapsulation module. Compared to methods that directly place hydrogen peroxide or peroxide materials near the encapsulated cell system, this invention can reduce the probability of exposure to residual hydrogen peroxide in the vicinity of cells, reduce the risk of decreased cell activity and functional decline caused by oxidative stress, and significantly improve the biosafety of the device.

[0148] 4. By adjusting diffusion parameters and catalytic capacity, the oxygen generation rate can be precisely matched with the total oxygen consumption rate of the cell, ensuring efficient oxygen delivery to the cellular region. The cell encapsulation oxygen generation device of this invention is adaptable to various cell encapsulation scenarios, such as pancreatic islets, and can achieve suitable oxygen supply configurations under different cell oxygen consumption levels, different encapsulation volumes, and different transplantation environments, significantly improving the device's versatility.

[0149] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A cell-encapsulated oxygen-generating device, characterized in that, The cell encapsulation oxygen generation device includes: a raw material storage module, a diffusion control module, and a cell encapsulation module, wherein... The raw material storage module is used to store hydrogen peroxide solution; The diffusion control module is disposed between the raw material storage module and the cell encapsulation module. The diffusion control module includes a catalytic chamber and an isolation structure. The catalytic chamber is designed to receive hydrogen peroxide molecules diffused from the raw material storage module; the interior of the catalytic chamber is provided with a catalyst, which is used to catalyze the hydrogen peroxide molecules entering the catalytic chamber to generate oxygen. The isolation structure includes a first isolation membrane and a second isolation membrane; the first isolation membrane is disposed between the raw material storage module and the catalytic chamber, and is used to control the hydrogen peroxide molecules to enter the catalytic chamber by diffusion; the second isolation membrane is disposed between the catalytic chamber and the cell encapsulation module, and is used to control the generated oxygen to enter the cell encapsulation module by diffusion. The cell encapsulation module contains a cell encapsulation matrix. This module receives oxygen diffused from the diffusion control module and supplies oxygen to the cells within the cell encapsulation matrix. The oxygen flux of the cell encapsulation oxygen generation device is regulated by diffusion parameters, including: the equivalent diffusion path length / film thickness, effective diffusion area, and equivalent diffusion coefficient of the first isolation membrane; the equivalent diffusion path length / film thickness, effective diffusion area, and equivalent diffusion coefficient of the second isolation membrane; and the hydrogen peroxide concentration difference between the raw material storage module and the catalytic chamber. The thickness of the first separator is 0.1~2mm, and the surface area is 50~300 mm². 2 ; The second separator has a thickness of 0.05~2mm and a surface area of ​​80~400 mm². 2 ; The initial concentration of the hydrogen peroxide solution is 0.1 wt% to 30 wt%. The thickness of the catalytic chamber is 0.1~2 mm, and the volume is 10~800 mm². 3 ; The catalyst is packed at a rate of 0.1~5 g / cm³. 3 .

2. The cell encapsulation oxygen generation device according to claim 1, characterized in that, The materials of the first and second separators are independently selected from at least one of polydimethylsiloxane, fluorosilicone rubber, polyurethane, polyethylene, polypropylene, polytetrafluoroethylene, fluorinated ethylene propylene, perfluoroalkoxyalkane, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polysulfone, nylon, polycarbonate, polyacrylonitrile, and cellulose.

3. The cell encapsulation oxygen generation device according to claim 1, characterized in that, The catalyst is disposed inside the catalytic cavity in any one of the following forms: powder filling, particle filling, porous bulk filling, or immobilized coating. The catalyst includes at least one of inorganic catalysts, noble metal supported catalysts, and enzyme catalysts.

4. The cell encapsulation oxygen generation device according to claim 1, characterized in that, The cell encapsulation matrix is ​​a hydrogel encapsulating cells; The hydrogel includes at least one of the following: alginate hydrogel, agarose hydrogel, polyethylene glycol diacrylate hydrogel, polyethylene glycol hydrogel, methacrylamide gelatin, hyaluronic acid hydrogel, fibrin hydrogel, chitosan hydrogel, dextran hydrogel, polyvinyl alcohol hydrogel, and Prönkel hydrogel.

5. The cell encapsulation oxygen generation device according to claim 1, characterized in that, The cell encapsulation module includes a recessed encapsulation cavity for accommodating the cell encapsulation matrix; The groove depth of the groove-type encapsulation cavity is 0.5~10mm, and the effective volume is 50~2000μL.

6. The cell encapsulation oxygen generation device according to claim 5, characterized in that, One end of the grooved encapsulation cavity is provided with an opening, and a sealing film is also provided at the opening to seal the grooved encapsulation cavity; The sealing film is a semi-permeable membrane with a pore size of 50~500nm and a thickness of 10~200 μm; The semipermeable membrane is made of at least one of polytetrafluoroethylene, polyethersulfone, polyvinylidene fluoride, polyacrylonitrile, polycarbonate, nylon, cellulose, and polyurethane.

7. The cell encapsulation oxygen generation device according to claim 1, characterized in that, The cell-encapsulated oxygen generation device further includes at least one of the following: a gas buffer structure, a liquid supply interface, and a residual raw material removal layer. The gas buffer structure is disposed between the second isolation membrane and the cell encapsulation module or embedded in the second isolation membrane, and is used to buffer the gas pressure fluctuations during the process of hydrogen peroxide molecules generating oxygen. The liquid replenishment interface is located on the raw material storage module and is configured as a disposable sealed interface or a replenishment interface that can be repeatedly opened and closed, for filling or replenishing hydrogen peroxide solution into the raw material storage module. The residual raw material removal layer is disposed between the second isolation membrane and the cell encapsulation module, and is used to capture and decompose unreacted hydrogen peroxide molecules.

8. The cell encapsulation oxygen generation device according to claim 1, characterized in that, The shape of the cell-encapsulated oxygen-generating device includes any one of sheet-like, disc-like, or strip-like structures; The height of the cell-encapsulated oxygen-generating device is 2-20 mm, and the lateral dimension is 10-60 mm.

9. An implantable medical device, characterized in that, The implantable medical device includes the cell encapsulation oxygen generation device according to any one of claims 1 to 8.

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