33 results about "Erythrocytes membrane" patented technology

The invention discloses an artificial blood vessel and a preparation method thereof, and the preparation method comprises the following steps: uniformly mixing an erythrocyte ghost suspension and melanin nanoparticles to obtain a mixed solution; carrying out ultrasonic treatment and extrusion on the mixed solution to obtain a melanin nano-vesicle solution; carrying out electrostatic spinning on the polycaprolactone solution to obtain a polycaprolactone electrostatic spinning blood vessel; soaking the polycaprolactone electrostatic spinning blood vessel in an ethylenediamine solution, and then washing the polycaprolactone electrostatic spinning blood vessel with a phosphate buffer solution; then soaking in a 4-morpholine ethanesulfonic acid solution; finally, carrying out heparinization in a 4-morpholine ethanesulfonic acid solution containing 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, N-hydroxysuccinimide and heparin; and incubating the heparin-modified polycaprolactone electrostatic spinning blood vessel in the melanin nano-vesicle solution to obtain the artificial blood vessel. The melanin nano-vesicles are modified, so that the anticoagulation performance of erythrocyte membranes is reserved, and meanwhile, the scavenging capacity of melanin nano-particles on reactive oxygen free radicals is reserved.

The invention relates to the technical field of medical nano-materials, and discloses a pH-responsive drug self-delivery nano-system and a preparation method and application thereof.The preparation method comprises the steps that 1, CMNPs is prepared, specifically, through an amidation reaction, the CMNPs are prepared from methotrexate and cis-aconitic anhydride; step 2, synthesizing DSPE-PEG-T12: synthesizing the DSPE-PEG-T12 by virtue of a nucleophilic addition reaction; step 3, preparing a T12 peptide modified erythrocyte membrane; and step 4, preparing T12-RBCM (at) CMNPs: modifying the T12 peptide of the targeted tumor cell transferrin receptor on an erythrocyte membrane, and coating the CMNPs to construct the nano-acquisition system T12-RBCM (at) CMNPs. According to the nano system T12-RBCM (at) CMNPs obtained by the scheme, the tumor cell uptake efficiency can be remarkably improved, cell apoptosis is induced, and proliferation is inhibited; the long-acting circulation and tumor targeting capability is realized, the tumor growth can be effectively inhibited, and the biological safety is good.

The invention discloses a spleen-targeted nano platform construction method suitable for tumor vaccination, and particularly relates to the field of vaccines.The spleen-targeted nano platform construction method comprises the steps that S1, CL15H6-DOPS LNPs, spherical polymer vesicles and erythrocyte membrane coated nano-particles are selected as spleen-targeted nano-carriers; s2, integrating an immunologic adjuvant; mn < 2 + > doped LNPs, ultrasonic response lipidosome and a CD3 antibody are selected to be coupled to serve as an integration material; s3, delivering in vivo; animal models are selected for in-vivo delivery and curative effect verification, and B16F10 melanoma mice, MC38 colon cancer mice and non-human primates are selected as the animal models respectively. By optimizing the chain length and the surface topological structure (such as spherical polymer vesicles) of the liposome, the spleen enrichment rate is remarkably increased, and the red marrow myeloid cell uptake efficiency is enhanced. By combining with common delivery of a manganese adjuvant, an STING channel is activated, secretion of type I interferon is promoted, and the proportion of antigen-specific CD8 + T cells and the tumor inhibition rate are increased.

The invention discloses a red blood cell room-temperature preservation solution as well as a preparation method and application thereof, and belongs to the technical field of biological medicines. The erythrocyte preservative comprises the following components in parts by weight: 1-200 parts of an anticoagulant, 1-200 parts of a blood cell stabilizer, 1-100 parts of a metabolic inhibitor, 1-100 parts of an electrolyte, 1-150 parts of an antioxidant and 350-1000 parts of deionized water, and the pH value of the erythrocyte preservative is 4.6-7.0. All the components in the preservative are mutually matched and have a synergistic effect, and the integrity of erythrocyte membranes can be kept through synergistic protection of the multiple components; the electrolyte equilibrium osmotic pressure is maintained, the antioxidant scavenges free radicals, and hemolysis is reduced; the preservation time is prolonged, and the cell morphology and function are good; the dependence on a cold chain is reduced, and the demand on deep hypothermia equipment is reduced.

The invention relates to dual-targeting bionic hydrotalcite inorganic nanoparticles as well as a preparation method and application thereof. The preparation method comprises the following steps: obtaining a fresh erythrocyte membrane; obtaining an aged erythrocyte membrane; adding a fresh erythrocyte membrane and an aged erythrocyte membrane into the hydrotalcite inorganic nano-particles according to a certain proportion, mixing and stirring, and centrifuging to obtain the bionic hydrotalcite inorganic nano-particles. The dual-targeting bionic hydrotalcite inorganic nano-particles have the beneficial effects that the dual-targeting bionic hydrotalcite inorganic nano-particles have dual-targeting capability of being delivered to parenchymal hepatic cells and hepatic macrophages in a balanced manner, and oxidative stress and inflammatory response can be relieved at the same time.

In the first aspect, at least one of phosphatidylinositol 4-kinase type 2 alpha, phosphatidylinositol 5-phosphate 4-kinase type 2 alpha and protein kinase C beta is used as a marker to prepare a detection reagent or a kit so as to realize diagnosis or auxiliary diagnosis of Parkinson's disease. The kinases detected in an erythrocyte membrane as the PD diagnosis marker have the following advantages: 1, hemoglobin interference can be effectively removed through hypotonic lysis / centrifugal separation, the detection stability is improved, and accurate discovery of the marker is facilitated; 2, the erythrocyte membrane is easy to obtain and noninvasive, so that great convenience is provided for popularization of detection; 3, the biomarker found based on the erythrocyte membrane can be popularized or combined with serum detection, and it is possible to efficiently and stably detect PD.

The invention discloses a borneol modified erythrocyte membrane coated dendritic macromolecule bionic nano drug delivery system and preparation and application thereof, the bionic nano drug delivery system comprises an erythrocyte membrane and a drug loaded dendritic macromolecule coated in the erythrocyte membrane, the surface of the erythrocyte membrane is modified with targeted molecule borneol, the drug is an anti-tumor drug, such as bufotalin. In combination with a nasal drop administration mode, not only can the brain targeting efficiency of the glioma treatment drug be improved, but also the glioma treatment drug has immune escape and tumor microenvironment response capabilities, the in-vivo circulation time of the drug is effectively prolonged, and the glioma treatment effect is further improved. The design that the dendritic macromolecules are coated with the modified erythrocyte membranes combines the biocompatibility of natural cell membranes and the multifunctionality of nanoparticles, and the dendritic macromolecules have huge application potential in the fields of drug delivery, immune regulation, detoxification, targeted therapy and the like.

The invention relates to the technical field of biological medicine, in particular to DNase I loaded lipidosome and application thereof. The invention provides a bionic long-acting deoxyribonuclease I (DNase I) liposome with free DNA (cfDNA) responsiveness and a dual-targeting function, the liposome is subjected to layered fusion modification through an erythrocyte membrane and a neutrophile granulocyte membrane, a release window is accurately regulated and controlled by utilizing a 4ME-PC proportion, and a liposome drug carrier for cfDNA targeted combination and accurate delivery of an inflammation part is realized. The polypeptide can be used for cfDNA-related inflammatory diseases, and has an important application prospect.

The invention is applicable to the technical field of synthetic biology and membrane bioengineering, and provides a fusion membrane system for constructing an artificial organelle and a construction method thereof, the fusion membrane system comprises: a pigment body membrane for light-driven ATP synthesis; the erythrocyte membrane is used for consuming ATP to drive ion transport; the fusion promoting component comprises cholesterol-PEG (Polyethylene Glycol)-(EIAALEK) 4 and cholesterol-PEG-(KIAALKE) 4; the pigmented body membrane and the erythrocyte membrane form a fused vesicle structure under the action of the fusion promoting component. The steps of protein purification and artificial lipid assembly are avoided, the operation process is simplified, functional recombination of a heterologous natural membrane protein module is achieved, an energy-self-sufficiency artificial organelle is constructed, the ATP utilization efficiency is remarkably higher than that of a physical mixed membrane system and is improved by about 2-3 times, and the application prospect is wide. And a feasible framework is provided for energy management and artificial organelle design in a synthetic biological system.

The present disclosure proposes a preparation method of a vesicle formed by an erythrocyte membrane encapsulating Newcastle disease virus, including: mixing a compacted erythrocyte solution, a phosphate buffered saline (PBS) solution, and Newcastle disease virus (NDV); centrifuging a resulting mixture of erythrocytes added with NDV; and resuspending and precipitating the centrifuged mixture with a PBS solution to obtain the vesicle formed by the erythrocyte membrane encapsulating Newcastle disease virus.

The invention relates to the field of anti-tumor drugs, and discloses a nano medical drug taking FABP5 as a target as well as a preparation method and application of the nano medical drug. The nano medical drug is prepared by integrating a lipid nano shell with pH response, cycloarginine-glycine-aspartic acid and an erythrocyte membrane, and encapsulating nano particles of superparamagnetic iron oxide and sgFABP5. The nano medical medicine has the application potential of synergistically enhancing the tumor treatment effect after the liver cancer radiofrequency ablation operation.

This invention relates to the field of antibody drug technology, and more particularly to a human recombinant single-chain antibody, nanoparticles, and nanomedicine compositions and their applications. This invention provides a human recombinant single-chain antibody specifically targeting PHD2, the amino acid sequence of which is shown in SEQ ID NO:2. The human recombinant single-chain antibody obtained by this invention is more stable than INP and exhibits better organ and tissue targeting. Combining this human recombinant single-chain antibody with mesoporous silica nanoparticles and erythrocyte membranes to prepare a nanomedicine composition, this nanomedicine composition has better therapeutic efficacy.

A polypeptide specifically binding to an erythrocyte membrane or a mutant thereof. The polypeptide or mutant thereof can be fused with various recombinant proteins. By using the binding property of the polypeptide or mutant thereof to erythrocytes and dynamically balancing the binding to and releasing from an erythrocyte membrane, the sustained release of a drug can be achieved, thereby prolonging the circulation half-life of the drug.

The invention discloses a construction method and application of a ratio-type electrochemiluminescence (ECL) biosensor based on an anti-fouling erythrocyte membrane, belonging to the technical fields of optoelectronic analysis, biosensing, and interfacial anti-fouling. In the present invention, an erythrocyte membrane with super-hydrophilicity and low membrane protein content is used as an efficient anti-fouling interface, and its good biocompatibility avoids the influence of chemical anti-fouling coatings on the biological activity of the ECL sensor. At the same time, electro-polymerized polyaniline nanowires are embedded in the anti-fouling erythrocyte membrane, enhancing its chemical stability and conductivity, thereby expanding the application of anti-fouling cell membranes in ECL analysis. C<subgt;3< / subgt;N<subgt;4< / subgt; is introduced as an internal standard to eliminate background signals and external interferences, so as to improve the detection accuracy of the biosensor. Based on this, the constructed ECL anti-fouling biosensor achieves ultrasensitive detection of human breast cancer cells MCF-7 in human serum, with a detection limit as low as 3 cells / mL.

The invention provides application of mitochondrial vesicles in reduction of mitochondrial DNA deletion mutation. The mitochondrial vesicles are prepared by wrapping mitochondria with erythrocyte membranes, the mitochondrial vesicles can be tested and verified to effectively reduce the mitochondrial DNA deletion mutation level in cells, metabolism and functions of mutant cells are improved, verification is further carried out in muscle cells of CPEO patients, and the clinical application prospect is wide. By implanting the mitochondrial vesicles, the mitochondrial DNA deletion mutation level in the CPEO patient muscle cells can be effectively reduced, which indicates that the mitochondrial vesicles have the potential of treating CPEO, and a new thought is provided for treating diseases related to mitochondrial DNA deletion mutation.

The present invention discloses an erythrocyte membrane nanodisc, a preparation method, and its application in assisted phototherapy. The erythrocyte membrane nanodisc comprises an erythrocyte membrane, a photosensitizing agent loaded onto the erythrocyte membrane, and a restrictor wrapped around the erythrocyte membrane, the restrictor being used to stabilize the morphology of the erythrocyte membrane. The erythrocyte membrane nanodisc is used in assisted phototherapy to enhance the permeability of the photosensitizing agent. The preparation method includes steps S1: obtaining an erythrocyte membrane; S2: loading the photosensitizing agent onto the erythrocyte membrane; and S3: wrapping the restrictor around the erythrocyte membrane to form a nanodisc. This solution can enhance the permeability of the photosensitizing agent by loading the nanodisc with the photosensitizing agent, thereby enhancing the phototherapy effect.

The invention belongs to the technical field of tumor drugs, and particularly relates to an intelligent nano bionic drug delivery system based on ZIF-8, a preparation method and application, adriamycin, DNAzyme and an aptamer are loaded on ZIF-8, and the preparation method comprises the steps that after adriamycin is loaded to a ZIF-8 nano carrier, DNAzyme is further adsorbed by means of electrostatic interaction, and the ZIF-8 nano carrier is loaded with the DNAzyme; the intelligent nano bionic drug delivery system based on ZIF-8 is characterized in that a DOX / Dz-coated ZIF-8-RM / Apt nano drug delivery system is prepared by using a DOX / Dz-coated ZIF-8-RM / Apt nano drug delivery system, then using an erythrocyte membrane to perform surface modification, and finally inserting an aptamer drug into the surface of the cytomembrane through a lipid insertion method, and the intelligent nano bionic drug delivery system based on ZIF-8 is used for relieving chemotherapy drug resistance and improving the anti-tumor immunity efficiency; and the effect of the medicine in the tumor is improved to the greatest extent.

The invention provides application of lipid as a marker in preparation of a product for diagnosis or auxiliary diagnosis of Alzheimer's disease and / or mild cognitive impairment. The invention also provides an application of a substance for extracting lipid or a substance for detecting the expression level of lipid in preparation of a product for diagnosis or auxiliary diagnosis of Alzheimer's disease and / or mild cognitive impairment. The lipid is one or a combination of more of DAG 38: 2, TAG (14: 0 / 24: 1 (15Z) / 20: 0), TAG 58: 2, TAG 55: 5, TAG 53: 1, TAG 49: 3, TAG 45: 2, TAG 43: 1, PS 42: 8, PI (22: 1 (11Z) / 14: 0), PI (18: 2 (9Z, 12Z) / 18: 1 (9Z)), PC (22: 5 (7Z, 10Z, 13Z, 16Z, 19Z) / 18: 0), LPC (24: 1 (15Z The substance for extracting the lipid is a combination of isopropanol and a mixture of isopropanol, acetonitrile and water in a volume ratio of 4: 3: 1. In the extraction of the lipid difference substances, the red cell membrane (RCM) is creatively used as an extraction object, an extraction method is provided for the lipid difference substances of AD in the red cell membrane, 15 potential AD biological diagnosis markers are finally determined, and lipids prompt chronic physiological changes and are closely related to the pathogenesis of AD.

The present invention discloses a method for preparing a highly targeted liver cancer contrast agent, comprising the following steps: (1) encapsulating a quantum dot mixture with Ti3C2MXenes, wherein the quantum dot complex is composed of carbon quantum dots and graphyne quantum dots in a weight ratio of 1:1-2; (2) preparing a suspension from the product obtained in step (1), adding a hybrid cell membrane and homogenizing the suspension to obtain a highly targeted liver cancer contrast agent; the hybrid cell membrane is composed of erythrocyte membrane and macrophage membrane in a membrane protein weight ratio of 1:1, and the weight ratio of the product obtained in step (1) to the hybrid cell membrane is 3:1. The liver cancer contrast agent obtained by the invention has high dispersion stability and can be stored in an aqueous solution for more than 60 days. At the same time, at a low dosage of 0.5 μg / mL, the photoacoustic signal PA value can reach more than 1 within 24 hours. Moreover, the contrast agent obtained by the present invention has excellent targeting, with a targeting efficiency of up to 32% for liver cancer tumors.

The application discloses an anti-red blood cell membrane antibody and application thereof, and relates to a heavy chain and a light chain, wherein the amino acid sequence of the variable region of the heavy chain is shown as SEQ ID NO:1, or is a conservative mutant obtained by adding, deleting, replacing or modifying one or more amino acids of the sequence; the amino acid sequence of the variable region of the light chain is shown as SEQ ID NO:2, or is a conservative mutant obtained by adding, deleting, replacing or modifying one or more amino acids of the sequence; the sequences of CDR1, CDR2 and CDR3 of the variable region of the heavy chain are shown as SEQ ID NO:3, SEQ ID NO:4 and SEQ ID NO:5; the sequences of CDR1, CDR2 and CDR3 of the variable region of the light chain are shown as SEQ ID NO:6, SEQ ID NO:7 and SEQ ID NO:8; and the anti-red blood cell membrane antibody is used in the construction of a bifunctional antibody reagent. The anti-red blood cell membrane antibody is used in chromatography detection, and rbc can be intercepted on a sample pad by processing on the sample pad, so that whole blood can be detected.

The present invention discloses a red blood cell membrane positively coated electrochemical biosensor (ROCMCB), its preparation method, and application, belonging to the field of biosensor technology. ROCMCBs are based on antibodies modified on the surface of the electrochemical biosensor by specifically binding the extracellular binding region of the CD47 receptor on the cell membrane. Through immunoaffinity interactions between the antibodies, positive assembly of red blood cell membranes (RBCMs) on the surface of glassy carbon electrodes (GCEs) is achieved. The positive orientation enables the cell membrane to bind more firmly to the electrochemical biosensor and maximizes the exposure of the conformation and catalytic activity of the peripheral membrane-anchored protein AChE, enabling accurate measurement of the biological activity of acetylcholinesterase (AChE), thereby serving as a platform for anti-AD drug screening.

The invention provides an erythrocyte microreactor as well as a preparation method and application thereof, and belongs to the technical field of biomedical engineering. Glucose oxidase (GOx) is entrapped in erythrocytes under a hypotonic condition, endogenous hemoglobin (Hb) is retained, and palmitate modified catalase (CAT) is fixed on the surface of an erythrocyte membrane, so that the erythrocyte microreactor is prepared. According to the invention, spatial separation and function synergy of enzyme distribution and synergistic effect of GOx / Hb intracellular catalysis and membrane surface CAT removal of by-product H2O2 are realized, cascade reaction efficiency and stability are effectively improved, and accurate regulation and control of NO generation can be realized. Experiments show that the microreactor has remarkable effects in the aspects of regulating NO steady state, improving glucose tolerance, relieving insulin resistance, stabilizing blood glucose and the like, has a lasting curative effect, low medication frequency and high biological safety, and has a wide application prospect in the aspects of biological catalysis and prevention and treatment of metabolic diseases such as diabetes mellitus.

The invention discloses a double-cell membrane fusion carrier and hydrogel synergistic double-drug system as well as preparation and application thereof, and relates to the technical field of biological medicine and tissue engineering. According to the invention, enzyme-triggered synergistic controlled release and MMP-9 enzyme sensitive design are adopted to realize double-drug synchronous sequential release, and an inflammation-osteogenesis repair process is accurately matched; according to the present invention, the BMP-2circRNA half-life period is prolonged to 96 h, the osteogenic gene (Runx2, OCN) expression quantity is increased by 4 times, the osteogenic differentiation is significantly promoted, the targeting and cycle performance is excellent, the RMHM vector mediates bone defect homing through the CXCR4 receptor, and the targeting efficiency is increased by 3.2 times compared with the traditional liposome; the erythrocyte membrane CD47 protein reduces the immunogenicity, the in vivo half-life period is prolonged to 36 hours, and the whole body exposure risk is reduced.

The present invention relates to the field of in vitro diagnostics, and more specifically to the preparation and application of anti-porcine erythrocyte membrane antibodies. Using porcine erythrocytes as immunogens, the present invention prepared a monoclonal antibody, 3B6, that can recognize porcine erythrocytes. The antibody has a heavy chain variable region as shown in SEQ ID NO: 1 and a light chain variable region as shown in SEQ ID NO: 2. Experimental results demonstrate that the antibody has strong specificity, high adhesion to erythrocytes, and high application value.

This invention relates to a biomimetic delivery system co-loaded with a radionuclide and a KDM5B degrading agent, its preparation method, and its application. The biomimetic delivery system includes liposomes, KDM5B degrading agent CMATACs encapsulated within the liposomes, and a radionuclide labeled on the surface of the liposomes. 177 Lu, erythrocyte membrane vesicles encapsulating the liposomes, and tumor homing peptide CREKA modified on the surface of the liposomes. Compared with the prior art, this invention achieves for the first time the synergistic delivery of "epigenetic regulation and targeted radionuclide therapy", and the prepared biomimetic delivery system has excellent in vivo anti-tumor effects and biosafety.

The invention discloses an erythrocyte membrane nanodisk, a preparation method and application of the erythrocyte membrane nanodisk in auxiliary phototherapy. Wherein the erythrocyte membrane nanoplate comprises an erythrocyte membrane, a photosensitive reagent loaded on the erythrocyte membrane and a limiter wrapping the periphery of the erythrocyte membrane, and the limiter is used for stabilizing the form of the erythrocyte membrane; the invention relates to an application of an erythrocyte membrane nano-plate in auxiliary phototherapy. The erythrocyte membrane nano-plate is used for enhancing the permeation of a photosensitive reagent. The preparation method comprises the following steps: S1, obtaining an erythrocyte membrane; s2, loading a photosensitive reagent on the erythrocyte membrane; and S3, wrapping the periphery of the erythrocyte membrane with a restrictor to form the nanodisk. According to the scheme, the photosensitive reagent can be loaded through the nanodisk, the permeation effect of the photosensitive reagent is improved, and the phototherapy effect is enhanced.

The present disclosure proposes a preparation method of a vesicle formed by an erythrocyte membrane encapsulating Newcastle disease virus, including: mixing a compacted erythrocyte solution, a phosphate buffered saline (PBS) solution, and Newcastle disease virus (NDV); centrifuging a resulting mixture of erythrocytes added with NDV; and resuspending and precipitating the centrifuged mixture with a PBS solution to obtain the vesicle formed by the erythrocyte membrane encapsulating Newcastle disease virus.

The invention discloses an agglutination-free mixed state red blood cell separation medium, a separation method and application, and every 100 mL of the agglutination-free mixed state red blood cell separation medium comprises 5.0 to 10.0 g of glucose, 5.0 to 15.0 g of bovine serum albumin, 0.580 to 0.655 g of disodium hydrogen phosphate, 0.020 to 0.027 g of sodium dihydrogen phosphate, 0.05 to 0.08 mL of a preservative and the balance of ultrapure water. The separation method comprises the following steps: mixing red blood cells with the monoclonal antibody, incubating at a proper temperature and fully reacting, transferring a mixed suspension containing the free red blood cells, washing, adding normal saline to dilute the concentration to 3-5%, and finally standing by using a separating medium to separate the free red blood cells. The method has the characteristics of one-time thorough separation, short separation time, no shrinkage deformation of separated free erythrocyte membranes and high recovery rate, and is suitable for separation of agglutination-free mixed erythrocytes.

The invention aims to provide a preparation method and application of a gouty arthritis diagnosis and treatment integrated bionic nanoprobe, and belongs to the technical field of life medicine and inorganic nanomaterials. An alloy structure formed by gold-platinum nano-clusters is constructed through a chemical reduction method to serve as an inner core of the nano-clusters, and the exterior of the nano-clusters is coated with an erythrocyte membrane to obtain the gold-platinum nano-clusters. The nanoprobe coats an erythrocyte membrane, and is long in cycle half-life period and high in safety. The nanoprobe has uricase-like activity and catalase-like activity, can degrade hydrogen peroxide as a byproduct of uric acid while degrading uric acid, and relieves oxidative stress damage. The enzyme-like activity can be improved through in-vivo and in-vitro mild photothermal therapy, and the treatment effect of the probe on acute gouty arthritis is comprehensively improved.

The present invention belongs to the technical fields of cell engineering and biochemical detection, and particularly relates to a structurally complete red blood cell membrane, a preparation method thereof, and an application thereof. The present invention lyses red blood cells by defining the components of a release solution, with mild conditions, which can release protein components such as hemoglobin inside the red blood cells, remove their cell attributes, retain the integrity of their internal skeleton structure and the activity of membrane surface antigens, and while maintaining the complete structure of the red blood cell membrane, retain the key blood group antigens on its surface, avoiding the problem of reduced antigenicity caused by fragmentation of the red blood cell membrane. After lysing the red blood cells, nanoparticles are conjugated to the surface of the red blood cell membrane, enabling the agglutination reaction of the red blood cell membrane induced by antibodies to be visualized. Using a fixed procedure to preserve the engineered red blood cell biomembrane can effectively avoid damage to the engineered red blood cell biomembrane by ice crystals, ensure that the antigenicity of the membrane is not affected, and can be stored at room temperature for a long time, with the shelf life extended to two years or more.