275 results about "Membrane permeability" patented technology

This invention features permeability enhancer molecules, and methods, to increase membrane permeability of various molecules, such as nucleic acids, polynucleotides, oligonucleotides, enzymatic nucleic acid molecules, antisense nucleic acid molecules, 2-5A antisense chimeras, triplex forming oligonucleotides, decoy RNAs, dsRNAs, siRNAs, aptamers, or antisense nucleic acids containing nucleic acid cleaving chemical groups, peptides, polypeptides, proteins, carbohydrates, steroids, metals and small molecules, thereby facilitating cellular uptake of such molecules.

The invention belongs to the technical field of lithium ion battery diaphragm, and provides a high-temperature resistant aromatic polysulfonamide base lithium ion battery diaphragm. The battery diaphragm is characterized in that the battery diaphragm has fiber diameter of 30-800nm, diaphragm thickness of 15-80 mum and membrane permeability of 3-100 s; pores on the upper and lower surface of the membrane and in the membrane are symmetrically and uniformly distributed, and have average pore size of 50-800nm; besides, the membrane has porosity of 70%-90%, and tensile strength of 10-50 MPa. The invention also discloses a preparation method of the aromatic polysulfonamide base diaphragm. Compared with a traditional polyolefin diaphragm, the aromatic polysulfonamide base diaphragm provided by the invention has good electrolyte wettability, excellent flame retardant performance and high temperature resistance performance. A lithium ion battery assembled from the diaphragm does not generate short circuit phenomenon under high temperature of 120 DEG C, and can charge and discharge quickly. Therefore, the high-temperature battery diaphragm provided by the invention is particularly applicable to the fields of power lithium ion battery and high temperature lithium ion battery.

The invention belongs to the technical field of membrane and relates to a photocatalytic composite ceramic separation membrane using porous ceramic membrane as a carrier, a method for preparing the same and application of the separation membrane. The method is characterized in that a porous ceramic membrane substrate is used as the carrier to prepare hydroxyapatite sol and argent-titania composite sol through sol-gel technology; and a carrier membrane is subjected to secondary sol-gel dipping, drying and roasting sequentially to obtain the argent-carried titania/hydroxyapatite photocatalytic composite ceramic separation membrane with aperture of between 100 and 1,900 nm and porosity of between 20 and 55 percent. The photocatalytic composite ceramic separation membrane has biological adsorption and high photocatalytic activity and membrane permeability, improves separation of the composite membrane, photocatalytic degradation and sterilization, has remarkable effects of decontamination and sterilization, reduces the loss of porosity in the process of membrane preparation, has a simple preparation and application process, is easy for large-scale industrial production, integrates three units of membrane separation, photocatalytic degradation and sterilization and reduces investment and occupied area.

Provided is a pharmaceutical composition for permeabilizing fetal membranes including an active ingredient having a log K in the range of 2 to 4, where K is the octanol/water partition coefficient. The active ingredient may be, for example, bupivacaine, sodium lauryl sulfate or oleic acid. Further provided is a system for transfetal membrane transport. The system includes a probe unit adapted for insertion into a female reproductive tract and releasing a substance onto fetal membranes that permeabilizes the membranes. The system is also configured to apply ultrasound radiation to the fetal membranes to further increase the membrane permeability.

The invention discloses a measuring method and a device for simultaneously measuring the membrane permeability of each gas in mixed gas. According to the measuring method and device, the combination of a gas chromatograph and a gas permeation tank for measuring the membrane permeability is realized, and the permeabilities of multiple components of a thin film and a flake material when the mixed gas permeates through the thin film and the flake material can be simultaneously and rapidly measured accurately one time; furthermore, in a connecting method disclosed by the invention, an air blowing system does not need to be arranged, the measuring method can be used for measuring the thin film with the diameter of 8mm or even smaller without that the gas passes through a quantitative feeding device, and a gas chromatography flame ionization detector has the enough sensitivity for measuring penetration gas after permeating for 5 minutes. By utilizing the measuring method and device, the interaction effect of each component to the permeation rate can be researched when the mixed gas permeates, and the diffusion coefficients of the solubility coefficients of the thin film and the flake material can be conveniently measured.

The invention discloses an indolpyridine type fluorescent probe for imaging RNA (Ribonucleic Acid) and nucleolus in a living cell. The structural general formula of the fluorescent probe is shown in the specification, wherein R1 and R2 represent alkyl, hydroxyalkyl or ether group, respectively. The invention also discloses application of the fluorescent probe in marking or displaying of the distribution of the RNA and the nucleolus in the living cell and distinguishing of the dead state and the live state of the cell. The probe provided by the invention has the characteristics of wide application range, good membrane permeability, low cytotoxicity and ability of exclusively realizing fluorescent imaging of RNA in the living cell.

The invention discloses a fluorochrome taking fluorescein as matrix, as well as a preparation method and application thereof. The fluorochrome taking the fluorescein as the matrix has the structure shown in a general formula I (figure 1); and the compound has a certain level of water-solubility, and has certain good membrane permeability. The compound disclosed by the invention has novel spectral characteristics; and dye of fluorescein derivative with good property is applied to the fluorescence imaging aspect.

A symmetric pentamethyl cyanine dye with a general formula I and application thereof to molecular imaging belong to the fields of organic compound and optical molecular imaging. In the general formula I, X represents Cl or S (CH2)nCOOH or II; R1 represents C1-6 alkyl, (CH2) pOR3 or (CH2) pC6H5; R2 represents H, methyl, hydroxy, halogen, nitro, benzyloxy, alkoxy or a water-soluble group SO3R4; and R4 represents H, sodium ion or potassium ion; and Y<-> represents halogen ion, PF6<-> or TsO<->. An asymmetric synthesis method is employed to prepare a pentamethyl cyanine dye fluorescence probe with the general formula I, in order to solve the problems of an asymmetric synthesis method, such as tedious steps, by-product and low yield. The dye has advantages of low toxicity, active cell membrane permeability and good light stability, and can be used for labeling live cells and in the field of molecular imaging.

The present invention is drawn to a method for enhancing secretional efficiency of a heterologous protein using a secretional enhancer consisting of a modified signal sequence which comprises the N-region of a signal sequence and/or a hydrophobic fragment of the said signal sequence comprising the said N-region and/or the hydrophilic polypeptide. The method of the present invention can be used not only for production of recombinant heterologous proteins by inhibiting insoluble precipitation and enhancing secretional efficiency of the recombinant protein into the periplasm or the extracellular fluid and but also for transduction of therapeutic proteins by enhancing membrane-permeability of the recombinant protein using a strong secretional enhancer.

A system and method for washing membrane by soft spherical particles and liquid flowing features that a washing liquid channel and a small particle circulator for releasing small particles are used to clean the surface of membrane, restoring the membrane permeability.

The invention discloses an ultrafilter washing enzyme and manufacturing method to improve permeabile content through ultrafilter washing enzyme, which is composed of ultrafilter enzyme 1# and 3#, pectase, cellulose enzyme, xylanase, beta-glucanase, beta-glucosidase. The making method comprises the following steps: washing through alkalin; adding 1000-3000ppm/t ultrafilter enzyme 1# and 500-1000ppm/t amylase in the circulating system to circulate 30-60 min; washing through alkali again; adding 1000-3000ppm/t ultrafilter enzyme 3# in the system to circulate 30-60 min; separating retention material on the film surface; improving the effect of chemical abluent; improving membrane permeability.

This invention improves the PAMPA (parallel artificial membrane permeability assay) method used in pharmaceutical, biotechnological, and agrochemical R&D. This new high-throughput method and apparatus for measurement of permeability and membrane retention of compounds overcomes shortcomings of prior art and includes sensitivity and speed enhancing reagents. The phospholipid membranes used here consist of 10–74% wt/vol soybean lecithin extract dissolved in dodecane. Concentrations are measured by direct UV spectroscopy. To reduce membrane retention, surfactants, cyclodextrins, or water-soluble lipophilic polymers with low UV absorption are used in the acceptor comparment of the permeation cells and create an artificial sink state. A pH gradient established between donor and acceptor solutions creates a secondary sink state. This “double-sink” makes successful modeling of passive-diffusion transport of molecules possible. By accelerating transport of certain molecules, it shortens measurement time and increases assay throughput. A new permeability equation accounts for the “double-sink” condition as well as membrane retention.

Compound solubility and permeability are coordinately determined. High throughput solubility assays are set up, and the filtrate from the solubility assay is used as an input for PAMPA. In this way, the compound concentration during PAMPA is known exactly, and can be used as input to calculate Pe.

The invention relates to a method of effectively producing 1, 3-propylene glycol by changing the membrane permeability, which adds nonionics to change the membrane permeability, effectively promotes the cell growth, and increases the concentration of 1, 3-propylene glycol which is the finished product of fermentation. The utility model has the technical process that as follows: adding the second-class germ culture into the fermentation culture; adding nonionics which can improve the membrane permeability to the fermentation culture; the nonionics reduce the resistance of the oxygen and nutrient substance from entering the cell, promote the cell growth, enhance the secreting of metabolite to the extra-cellular area, reduce the accumulation of metabolite in cell, and facilitate the elimination of inhibition of product and sub product, in particular the inhibition of cell growth and cell catalytic activity by 1, 3-propylene glycol. The concentration of the fermentation product--1, 3-propylene glycol is increased by 10 to 70 percent. With simple technical process and low production cost, the invention is easy to be industrially applied.

The invention discloses a 5'-O-amino acid ester hydrochloride, relating to the drug 1-beta-D-arabinofuranose-4-amino-2(1H)-cytosine ketone with interference on DNA synthesis, belonging to medical technique, in particular to a 5'-O-amino acid ester hydrochloride and a preparation method. The 5'-O-amino acid ester hydrochloride comprises 5'-O-L-valyl cytarabine hydrochloride, 5'-O-D-valyl cytarabine hydrochloride, 5'-O-L-isoleucyl cytarabine hydrochloride and 5'-O-L-tryptophanyl cytarabine hydrochloride. The preparation method is simple and suitable for industrial production, while the prepared product can effectively improve the membrane permeability of cytarabine, and the absolute biological utilization of mouse after oral taking can be improved from 21.6% to 60%.

The invention provides a method for retaining freshness of fresh-cut celery by combining ozone water washing and controlled atmosphere packaging. An ozone concentration in the ozone water is 0.9-1 milligram/L. Vacuum pre-cooling is carried out on fresh picked celery, screen grouping is carried out from aspects such as color, hardness and aroma, medium-well celery uniform in length and size is selected in each group, leaves removal, rib removal, cutting, washing and drying are carried out, the celery is filled in a controlled atmosphere packaging bag, 5% of O2, 10% of CO2 and 85% of N2 are filled in the packaging bag, heat sealing is carried out, and the celery is placed in a constant temperature and humidity box at the temperature of 2-4 DEG C for storage. The method has the advantages of effectively restraining reduction of sensory quality, increase of weight-loss ratio, decomposition of vitamin C and chlorophyll and increase of total bacterial count and membrane permeability. Compared with a control group washed by distilled water, the freshness retaining method can obviously prolong shelf life of the fresh-cut celery to 50 days. The freshness retaining method is simple, convenient, practical, low in cost, safe and free of residues.

A device for the measuring membrane permeability in electrical/electrochemical/photo-electrochemical fields is provided. The device comprises a permeation cell and a tube mounted within the cell. An electrode is mounted at one end of the tube. A membrane is mounted within the cell wherein a corona is discharged from the electrode in a general direction toward the membrane thereby generating heated hydrogen atoms adjacent the membrane. A method for measuring the effects of temperature and pressure on membrane permeability and selectivity is also provided.

The invention discloses a molecular design and preparation method of a nitric oxide fluorescent probe based on a double-response mechanism. The structure of the nitric oxide fluorescent probe can be represented by a general formula (I) (please see the formula in the description), wherein Spacer represents a single bond or acetylene bond or thiophene or substituted aryl unit, Ar represents one of an aryl group, a substituted aryl group, a heterocyclic aryl group and substituted aryl amine, and the substituted group can be one of a hydrophilic ether chain, a sulfonic acid group, quaternary ammonium salt and the like. The key steps of synthesis of the probe molecule can be achieved through a Suzuki coupling reaction or a C-H activation coupling reaction and the like. The probe molecule has the advantages of being high in sensitivity, good in selectivity, short in response time, good in membrane permeability, low in background noise, capable of achieving direct observation and fluorescence-ultraviolet-visible spectrum dual-band response and the like, is a brand-new sensing detection platform and has a good application prospect.

The invention provides a base sheet for optical sheet having excellent antisticking properties, high total transmittance, capability of inhibiting interference phenomenon and uneven brightness, and high economical efficiency and membrane permeability, consisting of a transparent base film and an antisticking layer laminated on one surface of the base film, and characterized in that the antisticking layer has filling materials and resin binder; the average thickness of the flat part of the antisticking layer is more than 50nm and less than 15nm; the average grain diameter of the filling materials is more than 70nm and less than 200nm; the average grain diameter of the filling materials can be larger than the average thickness of the flat part of the antisticking layer; the content of the filling materials of the antisticking layer is preferably more than 20 mass percent and less than 50 mass percent; and bonder polymer can have a three-dimensional crosslinking structure.