CN-122011871-A - Biosensor polymer outer membrane and preparation method thereof

CN122011871ACN 122011871 ACN122011871 ACN 122011871ACN-122011871-A

Abstract

The invention belongs to the technical field of medical instruments, and discloses a biosensor polymer outer membrane, a preparation method thereof and a biosensor comprising the outer membrane. The outer membrane structure comprises a double-layer structure of an inner membrane and a surface membrane, wherein the inner membrane and the surface membrane form an integral structure in a chemical crosslinking mode, the inner membrane is of a continuous compact structure or a micropore structure, the thickness is 10-100 mu m, the thickness of the surface membrane is 1-20 mu m, and the hydration performance, the anti-interference performance, the biocompatibility and the like of the current biosensor can be effectively improved.

Inventors

LI YANJUN
HUANG TAO
ZHANG SHUMENG
XU CONG
HAN JIANG
CHEN JINGHUA
XU FAN

Assignees

深圳希沃康医疗科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260415

Claims (10)

1. The outer membrane of the biosensor is a double-layer structure comprising an inner membrane and a surface membrane, the inner membrane and the surface membrane form an integral structure in a chemical crosslinking mode, the inner membrane is of a continuous compact structure or a micropore structure, the thickness is 10-100 mu m, the thickness of the surface membrane is 1-20 mu m, Wherein the inner layer film has a polymer structure represented by the following formula 1: General formula 1 Wherein the subscripts x, y, z and m are the molar contents of the individual blocks and do not represent the positional relationship of the blocks in the polymer molecule, x: y: m is 1-10: 1-10: 0-1, z is less than x, wherein when the structure is In the absence, z is zero, when the structure When not present, m is zero; The group A is selected from a 5-12 membered heterocyclic group containing 1-3 nitrogen atoms or a substituted C2-C6 alkenyl group, and in the substituted C2-C6 alkenyl group, the substitution refers to containing 1-3 substituents, and the substituents are selected from amino groups, carboxyl groups, hydroxyl groups, ester groups, acid anhydrides, mercapto groups and isocyanate groups, and when the group A is positioned in the middle of a molecular chain, the group A is a corresponding subunit structure; the group B is selected from C2-C6 alkenyl containing 1-3 substituents selected from carboxyl, sulfonic, phosphoric and sulfinic groups; the group C is selected from a brominated polyacid alkane structure, a cyclic sultone structure or a copolymer of a small molecular compound; the top film has a polymer structure represented by the following structural formula 2: General formula 2 Wherein, the Subscripts x, y, and z are the molar content of each block and do not represent the positional relationship of the blocks in the polymer molecule, and x: y: z is 1-10:1-10:0-1, when the structure is In the absence, z is zero; the group O is selected from C2-C6 alkenyl groups containing active groups; the group P is selected from groups containing betaine structures; the group Q is selected from hydrophilic olefinic structures.
2. The biosensor outer film according to claim 1, wherein, In formula 1: subscript x is y, m is 4-8, 1-9, 0-1; The group A is selected from a 5-12 membered heterocyclic group containing 1 or 2 nitrogen atoms or a substituted C2-C4 alkenyl group, and in the substituted C2-C4 alkenyl group, the substitution means that the substituted C2-C4 alkenyl group contains 1 or 2 substituents, and the substituents are selected from amino groups, carboxyl groups, hydroxyl groups, ester groups, acid anhydrides, mercapto groups and isocyanate groups; Or group a is selected from pyridine, bipyridine, imidazole, biimidazole, maleic anhydride, allylamine, butenamine, allyl alcohol, propenol, butenol, fumaric acid, itaconic acid, allyl mercaptan, 3-mercapto acrylic acid, vinyl isocyanate, isocyanate ethyl acrylate; The group B is selected from C2-C4 alkenyl containing 1 or 2 substituents selected from carboxyl, sulfonic, phosphoric and sulfinic groups; or the group B is selected from C2-C3 alkenyl containing 1 or 2 substituents selected from carboxyl, sulfonic, phosphoric and sulfinic groups; Or the group B is selected from vinylsulfonic acid, allylsulfonic acid, acrylic acid, crotonic acid, maleic acid, vinylphosphoric acid, vinylsulfinic acid; The group C is selected from 3-bromopropane phosphoric acid, 3-bromopropionic acid, 2-bromoethyl phosphoric acid, 4-bromobutyl phosphoric acid, 1, 3-propane sultone, 1, 4-butane sultone, 2-bromoacetic acid sultone, copolymer of any one of polyethylene glycol glycidyl ether, 1, 4-butanediol diglycidyl ether, triethylene glycol diglycidyl ether and neopentyl glycol diglycidyl ether and any one of 1, 4-amino-1, 3-benzene disulfonic acid, 2-amino-4, 6-disulfonic acid benzoic acid, 3, 5-amino-2, 4-disulfonic acid benzenesulfonamide and aniline disulfonic acid; or the group C is selected from 3-bromopropane phosphoric acid, 1, 3-propane sultone, polyethylene glycol glycidyl ether and copolymer of aniline disulfonic acid.
3. The biosensor outer film according to claim 1, wherein the inner film polymer structure is selected from the group consisting of: Structure 1 Wherein the molar ratio of the 4-vinyl pyridine (x) to the styrene (y) is 5:5 to 9:1, the molar ratio of the polyethylene glycol glycidyl ether to the aniline disulfonic acid is 1:1, and the dosage of the polyethylene glycol glycidyl ether/the aniline disulfonic acid is 5 to 20 percent of the mass of the poly (4-vinyl pyridine-co-styrene); Structure 2 Wherein the molar ratio of butenamine (x) to styrene (y) to allylsulfonic acid (m) is 5:4:1 to 8:1:1, or Structure 3 Wherein the molar ratio of 4-vinyl pyridine (x-z) to styrene (y) to maleic acid (m) is 5:4:1 to 8:1, and the amount of the 1, 3-bromopropane phosphoric acid is 1 to 10% of the mass of the poly (4-vinyl pyridine-co-styrene-co-maleic acid).
4. The outer membrane of claim 1, wherein the inner membrane polymer has a weight average molecular weight of 20 to 100 or 30 to 50, a number average molecular weight of 10 to 50 or 20 to 30, and a molecular weight distribution of 1.5 to 2.5.
5. The biosensor outer film according to claim 1, wherein, In formula 2: x is y, z is 4-8, 1-9, 1; The group O is selected from glycidyl methacrylate, glycidyl acrylate, allyl glycidyl ether, 2-glycidyloxyethyl (meth) acrylate, 3, 4-epoxycyclohexylmethyl (meth) acrylate, glycidyl oxyphenyl (meth) acrylate, tetrahydrofurfuryl glycidyl methacrylate, bisphenol-A diglycidyl methacrylate, isocyanate acrylate, vinyl isocyanate, hydroxyethyl methacrylate, 2-carboxyethyl acrylate, N-methylolacrylamide, N-dimethylaminoethyl (meth) acrylate, N-diethylaminoethyl (meth) acrylate, 2-mercaptoethyl (meth) acrylate, 3-mercaptopropyl (meth) acrylate, 4-mercapto-1-butene; The group P is selected from the group consisting of polycarboxybetaines, polysulfonabetaines, phosphatidylcholines such as methacryloxyethyl phosphorylcholine, methacryloxyethyl sulfobetaines, oxyethyl carboxybetaines methacrylate, allylphosphorylcholine; The group Q is selected from polyethylene glycol methacrylate, polyethylene glycol acrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, polyethylene glycol methyl ether acrylate, ethoxylated hydroxyethyl methacrylate, and ethoxylated bisphenol A diacrylate.
6. The biosensor outer film according to claim 1, wherein the top film polymer structure is selected from the following structures: Structure 4 Wherein the molar ratio of glycidyl methacrylate (x) to sulfobetaine (y) is from 5:5 to 1:9, or Structure 5 Wherein the molar ratio of glycidyl methacrylate (x) to phosphatidylcholine (y) to polyethylene glycol methacrylate (z) is 4:5:1 to 1:8:1.
7. The biosensor outer film according to claim 1, wherein, The weight average molecular weight of the surface film polymer is 2-10 ten thousand, or 2-5 ten thousand, the number average molecular weight of the surface film polymer is 1-5 ten thousand, or 1-2 ten thousand, and the molecular weight distribution of the surface film polymer is 1.5-2.5.
8. The method for preparing a biosensor outer film according to any one of claims 1 to 7, comprising the steps of: Step 1, dissolving a polymer represented by a structural formula 1 in a mixed solvent of ethanol and 10mM HEPES (4-hydroxyethyl piperazine ethane sulfonic acid) to form a solution with a mass concentration of 20-80 mg/ml, wherein the volume ratio of the ethanol to 10mM HEPES is 10:1-1:1, and marking the solution as a; Step 2, dissolving a cross-linking agent in a mixed solvent of ethanol and 10 mM HEPES to form a solution with the mass concentration of 20-100 mg/ml, wherein the volume ratio of the ethanol to 10 mM HEPES is 10:1-1, marking the solution as a solution B, uniformly mixing the solution A and the solution B according to the volume ratio of 10:1, coating the solution A and the solution B on an electrode, and curing the solution for 15-60 minutes; Step 3, dissolving the polymer represented by the structural formula 2 in a mixed solvent of ethanol and 10mM HEPES to form a solution with the mass concentration of 14-60 mg/ml, wherein the volume ratio of the ethanol to 10mM HEPES is 1:10-1:1, marking the solution as solution C, and coating the solution C on the electrode solidified in the step 2; And 4, placing the electrode in a constant temperature and humidity box for crosslinking, wherein the temperature is 20 ℃, the humidity is 60%, the time is 48 h, taking the electrode out of a crosslinking cabinet after the polymer solution is crosslinked on the electrode, placing the electrode in a PBS solution for soaking 2h, transferring the electrode into electrochemical testing equipment, and testing the linear response of the electrode in the glucose solution.
9. The method for preparing a biosensor outer film according to claim 8, wherein, The volume ratio of ethanol to 10mM HEPES in step 1) is 5:1 to 1:1, or 3:1; The mass concentration of the polymer represented by the structural formula 1 in the step 1) is 20-80 mg/ml or 60-mg/ml; the volume ratio of ethanol to 10mM HEPES in step 2) is 1:5 to 1:1, or 1:3; the mass concentration of the polymer represented by the structural formula 1 in the step 2) is 50-100 mg/ml or 80-mg/ml; The cross-linking agent in the step 2) comprises polyethylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, 1, 4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, glycerol triglycidyl ether, polypropylene glycol diglycidyl ether and mannitol diglycidyl ether; The volume ratio of ethanol to 10mM HEPES in step 3) is 1:3 to 1:1, or 1:1; The mass concentration of the polymer represented by the formula 1 in the step 3) is 80 to 120 mg/ml, more preferably 100 mg/ml.
10. A biosensor comprising the biosensor outer membrane according to any one of claims 1 to 7.

Description

Biosensor polymer outer membrane and preparation method thereof Technical Field The invention belongs to the technical field of medical instruments, and particularly relates to a biosensor outer membrane and a preparation method thereof, and a biosensor comprising the outer membrane. Background The biosensor is a device for converting the concentration of a substance to be detected into a detectable signal by means of a biomolecule specific recognition function, and is widely applied to the field of medical health. Compared with in-vitro monitoring, in-vivo monitoring of the implanted flexible sensor can provide real-time, accurate and continuous vital sign information, and has wider application prospects in the fields of medical diagnosis, health management, drug research and development and the like. Its widespread use still faces accuracy and stability problems. Inflammatory response and fibrotic encapsulation after sensor implantation are one of the important factors that lead to reduced accuracy and stability of the implanted biosensor. The direct contact of the sensor outer membrane with the object to be measured and the test environment is a key interface component for the long-term and accurate operation of the implantable biosensor. The core function is to regulate the mass transfer process of target molecule and to block the adsorption of interfering matter and nonspecific biological molecule. For implantable biosensors, the structure and performance of the outer membrane directly affects the accuracy and stability of the sensor during long-term operation in vivo. Currently, polymer materials based on polyurethane (TPU), nafion, and the like are mainly used in commercialization and leading-edge research to construct a sensor outer film. And the properties of the membrane are regulated and controlled in a mixing or compounding way. The method has a certain application foundation in the aspects of regulating and controlling the mass transfer and the electrochemical stability of small molecules. But still is susceptible to protein adsorption, biological contamination, and local microenvironment changes under long-term implant conditions, resulting in reduced sensing performance. As one of the unavoidable challenges of implantable biosensors, the acute inflammatory response induced after implantation and the subsequently formed fibrotic envelope can change the mass transfer conditions and local physicochemical environments (e.g., pH, oxygen partial pressure, etc.) around the adventitia, thereby causing signal drift and measurement errors. In addition, the existing outer membrane structure is difficult to realize effective balance among permeability, anti-interference capability, quick response performance, long-term stability and biocompatibility of target molecules such as glucose and the like, and further improvement of the overall performance of the implantable biosensor is limited. The zwitterionic material has the characteristics of super hydrophilicity and electric neutrality, and the amphoteric ions on the surface of the zwitterionic material can form strong hydrogen bond action with water molecules to form a tight hydration layer, so that the zwitterionic material becomes a physical barrier, effectively resists the adsorption and deposition of proteins on the surface of the sensor, reduces foreign body reaction, reduces adhesion of macrophages and fibroblasts, and ensures the accuracy, stability and service life of the implantable biosensor. The multilayer film system has the characteristics of functional decoupling and collaborative optimization, and can break through the upper limit of the performance of a single material, so that the performance of the sensor is further improved. Therefore, the development of the outer membrane system which ensures the effective transmission of target molecules and simultaneously takes account of biological pollution resistance, structural stability and biocompatibility has important significance for improving the long-term reliability of the implanted biosensor. Disclosure of Invention The present invention is directed to a biosensor outer membrane, a method for preparing the same, and a biosensor comprising the outer membrane structure, which can effectively improve hydration performance, anti-interference performance, biocompatibility, etc. of the current biosensor. According to one aspect of the present invention, it is an object of the present invention to provide a biosensor outer film, which is a double-layered structure comprising an inner film and a surface film, the inner film and the surface film forming an integral structure by chemical crosslinking, the inner film being a continuous dense structure or a microporous structure, having a thickness of 10 to 100 μm, the surface film having a thickness of 1 to 20 μm, Wherein the inner layer film has a polymer structure represented by the following formula 1: General formula 1 Wherein the subscripts x