Abstract: A biodegradable particulate vector for transporting biologically active molecules is prepared containing a nucleus for containing a biologically active molecule, a first layer of fatty acid compounds covalently bonded to the nucleus and a second layer of phospholipids hydrophobically bonded to the first layer. The nucleus is between 10 nm and 10 .mu.m in size and is formed of a cross-linked polysaccharide or oligosaccharide matrix onto which ionic ligands are uniformly grafted. The cross-linked polysaccharide may be dextran, cellulose or starch cross-linked with epichlorohydrin. The ligand may be an acidic compound selected from succinic acid, phosphoric acid, citric acid, glycine, alanine, glutamic acid and aspartic acid, or a basic compound such as choline, hydroxycholine, 2-(dimethylamino)ethanol or 2-(dimethylamino)ethylamine fastened onto the matrix via the acidic compound. The polysaccharide or oligosaccharide may be co-cross-linked with a protein such as keratin/collagen or elastase.

Abstract: A surface of specific reactivity is formed by adsorbing a modified block polymeric surfactant of the Pluronic-type, i.e., containing pendant poly(ethylene oxide) blocks attached at an end to poly(propylene oxide) center blocks and with specifically reactive groups at the unattached ends of the poly(ethylene oxide) blocks, upon a hydrophobic surface.

Abstract: The invention relates to a method of detection, a sensor and a test-kit which find application in immunological detection (e.g., immunoassay). The invention provides, inter alia, a method of detection, suitable for use in immunological detection of an entity, which method includes the use of a secondary species (as defined in the specification), the use of a first detectable species, and the use of a second detectable species. The method may include, for example, the use of a primary species, a secondary species, a first detectable species and a second detectable species. The primary species may be, for example, an antibody or a ligand. The secondary species may be, for example, an auxiliary species such as an auxiliary binder or an auxiliary ligand, or a species which has a part which is an auxiliary function. The entity to be detected may be an analyte species as such or may be an entity which carries or includes analytes species.

Abstract: A solid support having surface-attached carboxylic acid groups is reacted with an isoxazolium salt to form an activated support having enol ester and sulfonate groups. After washing to remove residual isoxazolium salt and base, the activated support is dried. A polypeptide is covalently or non-covalently bound to the support. The resultant immobilized polypeptide can be conveniently sequenced by N- and C-terminal sequencing methods. The support can be a polyvinylidene difluoride membrane or a glass fiber membrane having surface attached carboxylic acid groups, and the enol and sulfonate groups are provided by reacting the support with 2-ethyl-5'-phenylisoxazolium sulfonate. The dry support can be stored for at least about 3 months to achieve a peptide immobilization yield that is substantially the same as the yield obtained in the absence of drying.

Abstract: A chemical linking agent is formed of a di- or higher functional photoactivatable compound having at least one group that is charged under the conditions of use in order to provide improved water solubility. The linking agent contains two or more photoreactive groups in order to allow the agent to be used as a cross-linking agent in aqueous systems. The charged group can be provided by a radical that includes one or more salts of organic acids, onium compounds, or protonated amines, (and optionally one or more additional photoreactive groups) and the photoreactive groups can be provided by two or more radicals that include an aryl ketone. The onium compound can provide a quaternary ammonium, sulfonium or phosphonium group.

Abstract: The present invention relates to an optical solid-phase biosensor for the detection of molecules which can be labelled with a fluorescent dye for the identification of substances in solution, for which there exists a biomolecule (receptor) which specifically recognises these and is chemically bonded to the uppermost layer of one or more layers of polyions on the surface of the sensor, by measurement of the Forster transfer between another dye molecule which is bonded in one of the uppermost layers of the sensor, and the said dye molecule.

Abstract: An improved spacer material for improving the biocompatibility of a biomaterial and a method for making it in which a polyalkylimine is covalently attached to an aminated substrate and combined with a crosslinking agent which is at least difunctional in aldehyde groups. The polyalkylimine can be for example, polyethyleneimine and the crosslinking agent can be, for example, glutaraldehyde. Preferably, the crosslinking agent is applied in dilute solution and at a pH suitable to accomplish light crosslinking of the polyalkylimine and also provide aldehyde linkages at the interface between the biomolecule and the spacer.

Abstract: An improvement in enzyme linked immunoassays is disclosed wherein the enzyme is in the form of a water soluble polymer saccharide conjugate which is stable in hostile environments. The conjugate comprises the enzyme which is linked to the polymer at multiple points through saccharide linker groups.

Abstract: A method and apparatus for carrying out affinity purification of a ligate. The method comprising, (a) providing a ligate containing liquid to a first side of at least one porous hollow fiber membrane with a ligand immobilized thereto that binds and separates the ligate from the liquid, (b) withdrawing a first portion of the liquid from the first side of the porous hollow fiber membrane, (c) recirculating the first portion of liquid to the first side of the porous hollow fiber membrane, (d) repeating steps (a) to (c) until a majority of the liquid has flowed through the porous hollow fiber membrane, and (e) providing an elution solution to one side of the porous hollow fiber membrane under a pressure sufficient to cause the elution solution to flow into and through the membrane to effect disassociation of any ligate-ligand bonds wherein any ligate bound to the ligand is eluted with the elution solution.

Abstract: Polyolefin particles are chemically modified by oxidation to provide a large surface area and high loading. The particles result in low back pressure in column systems, and are economical to manufacture. The particles are useful as supports in a wide range of applications including general organic as well as biopolymer synthesis, library methods, purification processes and enzyme mediated processes. In a preferred embodiment, polyethylene or polypropylene particles are oxidized in a solution containing trifluoroacetic acid or trifluoromethane sulfonic acid, chromium trioxide and sulfuric acid to provide the particles with a chemically reactive irregular surface and open channels that extend below the surface and up to essentially the length of the radius of the particles resulting in increased surface area and decreased density. The particles have pendant functional groups produced by the oxidation and/or by subsequent chemical reaction.

Abstract: The present invention provided compositions, methods and kits for detection and quantitation of pathogenic organisms. The composition of the invention is an oligonucleotide probe comprising a bacteriophage covalently linked to one site on an oligonucleotide probe complementary to a conserved region of a pathogenic organism. At a second site, the oligonucleotide probe is linked to a matrix. The oligonucleotide probe contains a region complementary to one strand of a restriciton endonuclease recognition site or an oligoribonucleotide moiety. The number of pathogenic organisms present in a biological fluid sample may be quantitated in accordance with the method of the invention by combining the composition of the invention with the sample, allowing hybridization to occur. Hybridization generates a DNA-RNA hybrid, and by adding the appropriate nucleolytic enzyme capable of cleaving DNA-RNA hybrids; bacteriophage will be released for measurement.

Abstract: Insoluble supports are prepared which possess high surface areas and efficiently dispersed isocyanate groups. These reactive supports are useful for covalently binding proteins which preferably are enzymes and provide catalysts for conducting organic reactions.

Abstract: The combination of a phosphatase enzyme with a biocompatible carrier material produces materials which are useful in the repair of the skeleton and the promotion of new bone growth. The combination preferably involves covalent coupling between the enzyme and the carrier. The preferred carrier materials include fibrillar collagen and may be obtained by the demineralization of calcified tissues. The materials may include phosphoproteins or dentinal phosphophoryns which may be residual or may be added during the preparation of the materials. The incorporation of other organophosphates and inorganic phosphates may improve the rate of mineralization especially in older animals.

Abstract: The invention relates to activated support materials which comprise epoxy-substituted poly(meth)acrylamides, characterized in that:a) the base support contains aliphatic hydroxyl groups,b) the covalently bonded polymers are bonded to the support via a terminal monomer unit,c) the polymers contain monomer units of the formula I,d) the monomer units are linearly linked, ##STR1## in which R.sup.1, R.sup.2 and R.sup.3 independently of one another are H or CH.sub.3,R.sup.4 is H or alkyl having 1-5 carbon atomsandn is an integer between 1 and 5 and to the use thereof.

Abstract: A composition including a polyester containing one or more free COOH groups ionically conjugated with a bioactive polypeptide comprising at least one effective ionogenic amine, wherein the polyester contains a member selected from the group of L-lactic acid, D-lactic acid, DL-lactic acid, .epsilon.-caprolactone, p-dioxanone, .epsilon.-caprolic acid, alkylene oxalate, cycloalkylene oxalate, alkylene succinate, .beta.-hydroxybutyrate, substituted or unsubstituted trimethylene carbonate, 1,5-dioxopan-2-one, 1,4-dioxepan-2-one, glycolide, glycolic acid, L-lactide, D-lactide, DL-lactide, meso-lactide, and any optically active isomers, racemates or copolymers thereof, and at least 50%, by weight, of the polypeptide present in the composition is ionically conjugated to said polyester.

Abstract: The invention relates to magnetic protein conjugates of the formula I ##STR1## in which M represents a dispersible magnetically reacting material or particle which carries aminogroups, Ig represents a protein which carries one or more mercapto groups, and X represents an organic chemical structure which links the two ligands by chemical means, to a process for the preparation of protein conjugates of the formula I, and to the use of conjugates of this type for removing cells or soluble bioorganic molecules or components from aqueous salt solutions or body fluids, and to the use thereof within the framework of a diagnostic method or as a diagnostic aid.

Abstract: An improved coating and spacer material for a medical device having a blood or tissue-contacting surface comprising a polyalkyleneimine layer which is crosslinked with a crosslinking agent which is at least difunctional in polymerizable vinyl groups which have adjacent strong electron-withdrawing groups and a biomolecule covalently bonded to the crosslinked polyalkyleneimine layer. For example, polyethyleneimine crosslinked with divinyl sulfone could be used. The resulting crosslinked spacer layer has improved uniformity and stability without materially limiting the covalent attachment of a biomolecule such as heparin.

Abstract: A method for the isolation and sorting of biological materials has been developed. Biological material includes chromosomes, segments of chromosomes, cell organelles, or other minute cellular components. The biological material is separated from the cellular milieu, if necessary, and anchored to a support. Examples of a support are glass coverslips, glass or polymer beads. The anchoring is by means of a reversible polymer and cross-linking system. The supported biological material may then be labelled with compositions capable of binding to said material, and with magnetic particles. Examples of the binding material include nucleic acid probes and antibodies. An example of the antibodies would be those directed to histones. Other labels, for example, fluorescein-biotin-avidin may be used. The material may be released from the support and sorted by a magnetic force.

Abstract: A coupling agent which is an activated ester such as N-maleimido-6-aminocaproyl-HNSA (mal-sac-HNSA) is formed by reacting 4-hydroxyl-3-nitrobenzene sulfonic acid sodium salt (HNSA) with a carboxylic acid moiety of a compound such as N-maleimido-6-aminocaproic acid. The coupling agent is reacted with an amino group of an amine-containing biological material such as a protein at a pH of about 5.5 to 10.0 and HNSA is released. The released HNSA is spectroscopically measured at a wavelength of from about 350 nm to about 500 nm to precisely monitor and control conjugating of the coupling agent to the biological material. The resulting product is coupled to a sulfhydryl group or other group of another material to provide cross-linking between the two. This enables joining the biological material to one another, to a support matrix, to a label, to a hapten, and to other materials.

Abstract: Heterofunctional crosslinking agents are used to produce a device for detecting a target polynucleotide. Synthetic single stranded capture and detector polynucleotides are covalently immobilized to plastic surfaces by novel heterofunctional reagents. The capture and detector polynucleotides are covalently attached through a synthetic region of amine-bearing nucleotides that interact with reactive moieties on the heterofunctional crosslinker. The regions of the capture and detector polynucleotides that can hybridize a diagnostically important target polynucleotide are protected from binding to a solid phase support by intrastrand pairing. This system provides monolayers of immobilized polynucleotides with precise orientation and unimpaired diagnostic coding regions.

Abstract: A trifunctional conjugate is providing having three chemical moieties attached through a spacer moiety. At least two of the chemical moieties are relatively small molecules, usually less than about 7,000 Daltons in size. The spacer moiety is selected to impart certain steric properties to the conjugate. In one embodiment, the binding of a macromolecular specific binding partner to one of the chemical moieties sterically inhibits the binding of a different macromolecule to another chemical moieties. In another embodiment, the binding of a first chemical moiety to a macromolecule restricts the subsequent binding of a second tridentate member to a proximate location on the same macromolecule. The three chemical moieties are preferably a nitrophenylazido residue, a phenyl boronic acid residue, and a solid support or a label such as biotin. The spacer is preferably cysteine, lysine, glutamic acid, pyroglutamic acid, S-acetylmercaptosuccinic anhydride or .omega.-carbobenzoxylysine.

Abstract: Analytical reagents designated "release tags", for labeling molecular species with a highly detectable signal group which can be released in the form of a volatile compound at a desired point in an analytical procedure. In one embodiment, the release tags have the formula(SgCo).sub.x L(Rx).sub.rwherein each Sg is a signal group bearing one or more electronegative substituents, L is any of a wide variety of groups which when attached to a carbonyl group form a readily cleaved linkage, each COL moiety is a release group which upon scission releases signal group Sg in the form of a volative compound, and each Rx is a reactivity group for attaching the release tag compound to a molecular species to be labeled. In a second embodiment, the release tags have the formulaSgReRxwherein Sg and Rx are defined as above and Re is a release group which is an olefin, .alpha.-hydroxy ketone or vicinal diol. Conjugates of the release tag compounds and assay methods employing them are also disclosed.

Abstract: A method is disclosed for synthesizing peptides using water soluble enzyme polymer conjugates. The method comprises catalyzing the peptide synthesis with enzyme which has been covalently bonded to a polymer through at least three linkers which linkers have three or more hydroxyl groups. The enzyme is conjugated at lysines or arginines.

Abstract: A method of preparing (e.g., priming) a surface for attachment of a target molecule to the surface. The method provides a multifunctional reagent having multiple photoreactive groups. The groups can be activated in order to covalently bind one or more of them to the surface in such a manner that one or more will remain unbound. The unbound groups are then capable of reverting to their activatable state, whereupon they can again be activated in order to bind a target molecule having abstractable hydrogen atoms.

Abstract: A lens storage container having an interior coated with an enzymatic cleaning composition useful for cleaning and disinfecting contact lenses.

Abstract: Low density fused fibrous ceramic composites are prepared from amorphous silica and/or alumina fibers with 2 to 12% boron nitride by weight of fibers, used as a fluxing agent to reduce the melting temperature of the fibers and allow the fibers to fuse at their intersections creating a three dimensional rigid matrix. The matrix is useful as a cell-culture substrate, as an implant material, and for chromatographic separation of blood cells.

Abstract: Poly(ethylene glycol)-N-succinimide carbonate and its preparation are disclosed. Polyethylene glycol (PEG) is converted into its N-succinimide carbonate derivative. This form of the polymer reacts readily with amino groups of proteins in aqueous buffers. The modified proteins have PEG-chains grafted onto the polypeptide backbone by means of stable, hydrolysis-resistant urethane (carbamate) linkages.

Abstract: D-amino acid oxidase (DAO) in purified, partially purified or crude form is immobilized on a porous bead-shaped support that is a copolymer of vinyl acetate and/or vinyl alcohol and a crosslinking agent. A preferred crosslinking agent is N,N'-divinylethyleneurea. The amount of crosslinking agent is 1 to 60% by weight of the copolymer, and acyloxy groups of vinyl acetate may be present on the support as such or may have been hydrolyzed to hydroxyl groups. The support preferably has a mean particle size of 20 to 800 .mu.m and a mean pore diameter of 2 to 10,000 nm. The D-amino acid oxidase is preferably obtained from Trigonopsis variabilis and purified by ion exchange chromatography. The D-amino acid oxidase may be covalently bonded to a spacer such as epichlorohydrin or its homolog that is bound to the support. Catalase may also be immobilized.

Abstract: Stable suspensions of coated magnetic particles, preferably resuspendable bioactive particles particularly useful in Magnetic Resonance Imaging, are produced by disrupting, what are presumed to be, crystalline agglomerates of a parent particulate magnetic starting material in the presence of a coating material, such that coating can take place during the disruption. The particles are generally coated in suspension yielding a stable suspension of subdivided particles. With the proper selection of a coating material, preferably a protein or other biochemically or biologically active polymer such as an antibody, a resuspendable (colloidal) bioactive product is obtained.

Abstract: A biologically active support for removing pollutants from a fluid stream such as waste water is prepared. The support is formed of a polymeric foam substrate coated with a composition containing a particulate adsorbent which adsorbs, then releases pollutants, and a polymeric binder that binds the adsorbent to the surface of the substrate. The binder contains a suspension aid, and one or more pollutant-degrading microorganisms are adhered to the surface of the coated support. The binder preferably has a T.sub.g of lower than or equal to about 250.degree. C. and may be a latex. Examples of suspension aids are surfactants and polyanionic polypeptides such as ammonium caseinate. The adsorbent is preferably a carbon material such as coal, charcoal, carbon black and activated carbon. Other adsorbents are silica gel, active clays, zeolites, hydrophobic and ion exchange resins, and molecular sieves.

Abstract: Transesterification involving a fat, or a fat and fatty acid, or a phospholipid is carried out with a lipase or phospholipase immobilized on a polymer carrier. The transesterification is preferably carried out in a system containing a very small amount of water such as 50 to 2,000 ppm. The phospholipase can be phospholipase A.sub.2. In a first embodiment, lipase from a microorganism of the genus Rhizopus, Mucor, Alcaligenes or Candida is immobilized on the surface of a hydrophobic, insoluble organic polymer carrier having pores of an average diameter of 10 nm or larger and having on the surface epoxy groups capable of covalently binding lipase. The immobilized lipase is dried under reduced pressure. In a second embodiment, lipase is immobilized on the surface of a polymer carrier such as a hydrophobic, insoluble organic polymer carrier having a pore diameter of 5 to 1,000 nm and having on the surface a functional group capable of binding lipase and an anion-exchange group.

Abstract: A chemical specie is immobilized in a three dimensional, crosslinked matrix by bringing together in covalent bonding proximity a desired chemical specie and a polymeric coupling compound such as a photoderivatized polymer having at least two latent photochemical reactive groups per molecule, each latent reactive group being capable when activated of covalently bonding to another coupling compound molecule or to the chemical specie. The chemical specie may be a protein, carbohydrate, nucleic acid or lipid, and desirably is free of latent reactive groups that are activated upon activation of the latent reactive groups of the coupling compound. The latent reactive groups are simultaneously activated to cause formation via covalent bonding of a three-dimensional molecular network in which molecules of the chemical specie are covalently bonded to molecules of the coupling compound, and molecules of the coupling compound are covalently bonded to each other.

Abstract: A process for preparing glucose-1-phosphate from an .alpha.-glucan and orthophosphate using a phosphorylase immobilized onto an anion-exchange resin is disclosed. The anion-exchange resin used is a synthetic polymer resin into which an anion exchange group; a primary to quarternary ammonium group, a phosphonium group, or a sulfonium group, is introduced. This type of immobilized phosphorylase ensures (i) an effective utilization of phosphorylase, (ii) a higher reactivity of a higher absorbance of the phosphorylase to the resin, (iii) an excellent phosphorylase activity retention performance, and (iv) a higher physical strength of the resin.

Abstract: A granular polymer composite comprising polymeric granules having coated on a surface thereof a calcium phosphate compound, at least a part of the particles of the calcium phosphate compound penetrates into the polymeric granules. The composite has a high bonding strength between the polymeric granules as a matrix and a coating of the calcium phosphate compound and also can fully exhibit the functions of a calcium phosphate compound. Using the granular polymer composite, a diagnostic agent which comprises of an antigen or antibody is adsorbed and immobilized on the composite and is therefore useful in diagnostic tests utilizing an antigen-antibody reaction for a number of infectious diseases.

Abstract: A method for preparing an immobilized enzyme conjugate, whereby the enzyme is treated with a polyfunctional amine reactive material for forming a treated enzyme-containing adduct before being immobilized on a solid support which has been contacted with a solution of a polyamine compound. The method is especially preferred for use with glucoamylase, fungal .alpha.-amylase and .beta.-amylase. Immobilized enzyme conjugates formed by use of this method include treated enzyme-containing adducts. The immobilized enzyme conjugates disclosed herein are more stable and the enzymes immobilized therein are more tightly-held than those otherwise obtained and provided.

Abstract: A novel heterogenous purification method is disclosed. The method removes a macromolecule from a liquid by allowing the macromolecule to undergo a specific binding affinity reaction with a bidentate conjugate. The method is carried out by immobilizing the bidentate conjugate on a solid phase, contacting the bidentate conjugate with the liquid comprising the macromolecule, and separating the immobilized bidentate conjugate from contact with the liquid, thereby removing the macromolecule from the liquid to obtain either purified macromolecule or a purified liquid.

Abstract: A surface of specific reactivity is formed by adsorbing a modified block polymeric surfactant of the Pluronic-type, i.e., containing pendant poly(ethylene oxide) blocks attached at an end to poly(propylene oxide) center blocks and with specifically reactive groups at the unattached ends of the poly(ethylene oxide) blocks, upon a hydrophobic surface.

Abstract: Biochemical substances, such as enzymes, are immobilized using an olefinic-unsaturated, epoxyfunctional polysiloxane. The polysiloxane is applied to a carrier material. The polysiloxane on the carrier is cross-linked by using high-energy radiation or a peroxide to form a polymer matrix. The polymer matrix is treated with an aqueous solution of a biochemical substance that reacts with epoxy groups and becomes immobilized. The polymer matrix is stabilized by the reaction of non-reacted epoxy groups with a compound containing an amino group, a carboxyl group or an amino group and a carboxyl group. The crosslinked polysiloxane can be hydrophilized after cross-linking and prior to immobilization of the biochemical substance by the reaction of a portion of the epoxy groups with a hydrophilic compound.

Abstract: This invention is directed to water soluble protein polymer conjugates which are stabile in hostile environments. The conjugate comprises a protein which is linked to an acrylic polymer at multiple points through saccharide linker groups.

Abstract: Poly(fluoroalkyl) sugar reagents are prepared containing a sugar such as a monosaccharide or a disaccharide to which are bonded a plurality of fluoroalkyl anchor groups capable of attaching to a fluorocarbon surface, and either a reactive group capable of covalent coupling to a biomolecule such as an enzyme or a charged group to form an ion-exchanger or a non-ionic group to give a neutral fluorosurfactant. A spacer may be between the reactive group and the sugar. The poly(fluoroalkyl) sugar reagents are strongly adsorbed onto fluorocarbon surfaces to provide supports for such applications as separation and immobilization of biomolecules such as enzymes, carrying out heterogeneous diagnostic assays, and preparation of biosensors.

Abstract: A reusable, miniature, implantable electrochemical sensor, a method of making the same, and a powder therefor are provided. Enzyme material is immobilized on bulk particulate matter, and a reaction chamber of the sensor is then filled therewith. The sensor is implanted in an environment where it comes into contact with a specific component of a fluid with which the enzyme material chemically reacts to produce electrical signals for measuring the reaction. The method preferred for preparing the powder which is used in the electrochemical sensor involves first covalently bonding a quantity of an enzyme to fine particles in powder form to immobilize the enzyme is cross-linked to a non-enzyme protein with a cross-linking agent. Finally, the particles are added containing the immobilized enzyme cross-linked to a protein from the first step to the enzyme cross-linked to a protein from the second step to obtain the powder.

Abstract: A method for preparing an immobilized enzyme conjugate, whereby the enzyme is treated with a polyfunctional amine reactive material for forming a treated enzyme-containing adduct before being immobilized on a solid support which has been contacted with a solution of a polyamine compound. The method is especially preferred for use with glucoamylase, fungal .alpha.-amylase and .beta.-amylase. Immobilized enzyme conjugates formed by use of this method include treated enzyme-containing adducts. The immobilized enzyme conjugates disclosed herein are more stable and the enzymes immobilized therein are more tightly-held than those otherwise obtained and provided.

Abstract: A hydrophobic polymer such as polysulfone or polyethersulfone is modified to contain an increased number of functionalizable chain ends such as by treating with an alkali hydroxide to provide hydroxyl groups. A linker is covalently bonded to a chain end of the polymer and a macromolecule is covalently bonded to the linker. A ligand may be covalently bonded to the macromolecule. The macromolecule can be a natural polymer, a synthetic polymer or a biologically active species. The hydrophobic polymer is preferably in the form of a microporous membrane. By the use of a four-component dope composition, substantially isotropic microporous structures in the form of flat sheets or hollow fibers are produced. An improved spinnerette assembly is provided for the production of hollow fibers.

Abstract: A filter and a hollow-fiber or flat-sheet membrane for removing hemoglobin from whole blood or blood fractions are disclosed. The filter comprises a laid textile web which has been modified to attach a ligand for hemoglobin. The membrane comprises a polyethersulfone membrane that has been similarly modified. Methods for removing hemoglobin, cellular components and debris from blood are also disclosed.

Abstract: A method of separating cell nuclei from cells comprises: treating a fluid containing whole cells so as to selectively lyse the cytoplasmic membrane together with a small proportion of the nuclear membranes but leaving a large proportion of the cell nuclei intact; applying the treated fluid to a membrane whereby a mesh of DNA from the lysed nuclei is formed on the surface and captures intact cell nuclei. A device for use in the method is described.

Abstract: An immobilized lipase is prepared for transesterification of oils, fats or phospholipids in a reaction system containing a very small amount of water such as 50 to 2,000 ppm. The lipase may be a phospholipase such as phospholipase A.sub.2. In a first embodiment, lipase from a microorganism of the genus Rhizopus, Mucor, Alcaligenes or Candida is immobilized on the surface of a hydrophobic, insoluble organic polymer carrier having pores of an average diameter of 10 nm or larger. A solution of lipase is contacted with the polymer carrier for 10 minutes to 40 hours to covalently bond the lipase to the carrier. The immobilized lipase is dried under reduced pressure to a water content of 0.5 to 30 wt %. In a second embodiment, lipase is immobilized on the surface of a polymer carrier such as a hydrophobic, insoluble organic polymer carrier having a pore diameter of 5 to 1,000 nm and having a functional group capable of binding lipase in a aqueous solution and an anion-exchange group on the surface.

Abstract: Enzymes, cells and/or cellular organelles are bound to an insoluble sintered expanded clay support matrix for catalyzing transformations of agriculture and industrial residues in soil and in other environments. In one embodiment, an enzyme is absorbed by the sintered expanded clay support matrix and a phenolic monomer is polymerized or copolymerized on the support matrix containing the bound enzyme. In another embodiment, an enzyme different from the enzyme absorbed by the support matrix is combined with the phenolic monomer and a copolymer of enzyme and phenolic monomer is formed on the support matrix containing the bound enzyme. The phenolic monomer is preferably catechol, pyrogallic acid and/or resorcinol.

Abstract: A chelating agent is covalently bonded to a biologically active molecule such as an enzyme or antibody, the biologically active molecule is contacted with a support containing a bound transition metal ion whereby the metal ion is chelated by the chelating agent and the oxidation state of the metal ion is changed by treatment with an oxidizing or a reducing agent to provide a kinetically inert: oxidation state to immobilize the biologically active molecule on the support. The transition metal ion is preferably Co(II), Cr(II) or Ru(III) and the oxidation state of the metal ion is changed to Co(III), Cr(III) or Ru(II), respectively. The chelating agent can be iminodiacetic acid, nitrilotriacetic acid, terpyridine, bipyridine, triethylenetetraamine, biethylenetriamine, 1,4,7-triazacyclonane or a chelating peptide. Certain chelating agents can immobilize more than one biologically active molecule at a metal ion site on the support.

Abstract: Water-soluble compounds derived from a homopolymer or copolymer of maleic anhydride, and applications of the said compounds to supporting biological moleculesWater-soluble compound derived from a homopolymer or copolymer of maleic anhydride having available anhydride functional groups and hydrolyzed anhydride functional groups, wherein the hydrolyzed anhydride functional groups consist of carboxyl functional groups and functional groups derived from carboxyl functional groups carrying a residue of a compound corresponding to the formula I:C.sub.x H.sub.y A.sub.z O.sub.tin which:- A is the nitrogen atom of a primary, secondary or tertiary amine functional group or the sulfur atom of a thiol functional group,- x, z and t, independently of each other, are non-zero integers, and- y is a non-zero integer, not less than 5 when A is a nitrogen atom and not less than 4 when A is a sulfur atom.

Abstract: Heterobifunctional crosslinking agents are synthesized that covalently link molecules such as enzymes, cells, proteins and nucleic acids to a plastic substrate. The agents contain a central ring structure having a hydrophobic hydrocarbon chain that binds to a plastic substrate and distal to the hydrophobic chain one or more hydrophilic chains terminating in a reactive group that covalently binds the molecule. Immobilized molecules are useful in diagnostic assays or bioreactors.