Abstract: A plurality of particles of from about 5 nm to 100 ?m possessing predetermined isoelectric points in the pH range of from about 2.5 to 11 is used in a method of detection of a plurality of analytes, wherein the isoelectric particles of each isoelectric point further contain as label and a member of a binding pair capable of interacting with a selected analyte. The particles that form specific binding pairs are recovered and separated by isoelectric focusing followed by the detection of the labels associated with the particles. A flow cytometer may be used as a detector of the isoelectric particles.

Abstract: A plurality of particles of from about 5 nm to 100 ?m possessing predetermined isoelectric points in the pH range of from about 2.5 to 11 is used in a method of detection of a plurality of analytes, wherein the isoelectric particles of each isoelectric point further contain as label and a member of a binding pair capable of interacting with a selected analyte. The particles that form specific binding pairs are recovered and separated by isoelectric focusing followed by the detection of the labels associated with the particles. A flow cytometer may be used as a detector of the isoelectric particles.

Abstract: A plurality of particles of from about 5 nm to 100 ?m possessing predetermined isoelectric points in the pH range from about 2.5 to 11 is used in a method of detection of a plurality of analytes, wherein the isoelectric particles of each isoelectric point further contain a label and a member of a binding pair capable of interacting with a selected analyte. The particles that formed specific binding pairs are recovered and separated by isoelectric focusing, followed by the detection of the labels associated with the particles. A flow cytometer may be used as a detector of the isoelectric particles.

Abstract: A preparative electrophoresis apparatus suitable for recovery of molecules from gels comprises two spaced apart electrode compartments connected by a conduit that descends from the bottom of the electrode compartments in a V-shaped or U-shaped form. The conduit serves as a reservoir for collecting electroeluted molecules. Two electrophoresis buffers are used, a first one of a low concentration and density, and a second one of a high concentration and density. The electrode compartments are filled with the first electrophoresis buffer solution while the conduit is filled with the second electrophoresis buffer solution. Under the influence of an electric field, the molecules exit the gel and concentrate in the high concentration buffer. After a certain time, usually a time that is sufficient for driving substantially all desired molecules out of the gel, the electric field is switched off. The high concentration buffer containing the electroeluted molecules is withdrawn from the conduit.

Abstract: A plurality of particles of from about 5 nm to 100 ?m possessing predetermined isoelectric points in the pH range from about 2.5 to 11 is used in a method of detection of a plurality of analytes, wherein the isoelectric particles of each isoelectric point further contain a label and a member of a binding pair capable of interacting with a selected analyte. The particles that formed specific binding pairs are recovered and separated by isoelectric focusing, followed by the detection of the labels associated with the particles. A flow cytometer may be used as a detector of the isoelectric particles.

Abstract: A preparative electrophoresis apparatus suitable for recovery of molecules from gels comprises two spaced apart electrode compartments connected by a conduit that descends from the bottom of the electrode compartments in a V-shaped or U-shaped form. The conduit serves as a reservoir for collecting electroeluted molecules. Two electrophoresis buffers are used, a first one of a low concentration and density, and a second one of a high concentration and density. The electrode compartments are filled with the first electrophoresis buffer solution while the conduit is filled with the second electrophoresis buffer solution. Under the influence of an electric field, the molecules exit the gel and concentrate in the high concentration buffer. After a certain time, usually a time that is sufficient for driving substantially all desired molecules out of the gel, the electric field is switched off. The high concentration buffer containing the electroeluted molecules is withdrawn from the conduit.

Abstract: The device of present invention is used for cutting and recovery of a selected gel piece from a larger gel mass. The gel piece suitably contains molecules that will be used in further work. The preferred device is made up of at least two parts: a hollow member with a distal end terminating in a cutting edge, a proximal end, and a lumen in between the proximal and distal ends; and a piston member. The lumen part of the hollow member close to the proximal end has a larger cross section than a lumen part close to the distal end. The piston body has at least a first body that fits snugly in the lumen part having the larger cross section and a second body is longer than length of the lumen part with a smaller cross section and fits within the smaller cross section portion of the hollow tube, creates reduced pressure when moved towards proximal end of the hollow tube is disposed within the lumen.

Abstract: A gel for electrophoresis in a horizontal mode which contains at least one sample well with an enlarged loading area that is formed in an elevated gel segment. At least a front wall of the sample well consists of a substantially vertical part and a non-vertical part, where the non-vertical part is declined at an angle sufficiently steep that the sample loaded on the non-vertical part slides down into the sample well. Any sample molecules that during electrophoresis enter the gel through the non vertical part of the front wall migrate only through the elevated gel segment. They also exit this segment, so that substantially no double bands, which could complicate the interpretation of experimental results, are detected.

Abstract: Electrophoresis gels of enhanced selectivity are produced by adding a preformed polymer to a polymerization solution containing at least one monomer and at least one cross-linker. The polymer must be of such a chemical composition and molecular weight that its presence during free-radical polymerization results in a new topology of gel polymers, so that under the influence of an electric field, such as during electrophoresis, the passage of long DNA molecules through the gel is retarded proportionally more than the passage of the short ones. The polymer needs to be added at specific ratio to the monomer and the cross-linker, and the enhanced selectivity is achievable only within a certain range of ratios of polymer(s), monomer(s) and cross linker(s). That range is dependent on all three essential gel components, the polymer, the monomer and the cross-linker.

Abstract: A gel for electrophoresis in a horizontal mode which contains at least one sample well with an enlarged loading area that is formed in an elevated gel segment. At least a front wall of the sample well consists of a substantially vertical part and a non-vertical part, where the non-vertical part is declined at an angle sufficiently steep that the sample loaded on the non-vertical part slides down into the sample well. Any sample molecules that during electrophoresis enter the gel through the non-vertical part of the front wall migrate only through the elevated gel segment. They also exit this segment, so that substantially no double bands, which could complicate the interpretation of experimental results, are detected.

Abstract: A method of gel electrophoresis carried out in a submerged gel mode in which the gel is a bed of water insoluble, transparent, cross linked gel, which has been formed by: dissolving a polysaccharide, including at least one linear polysaccharide such as agarose or hydroxyethyl cellulose, in a suitable solvent, such as water; adding a cross linking agent, which is not charged nor becomes charged upon contact with water in a pH in the range of about 2 to 11, to the solution; and incubating this mixture in a quiescent state to substantially simultaneously react the polysaccharide and the cross linking agent and to gel the reaction product into a bed. The polysaccharide is at least one linear polysaccharides, but that linear polysaccharide may also be admixed with other linear polysaccharides and/or at least one non-linear polysaccharide. Synthetic organic polymers may also be admixed in the cross linking reaction mixture.

Abstract: A bed of water insoluble, transparent, cross-linked gel, suitable for use in electrophoresis, is formed by dissolving a polysaccharide, including at least one linear polysaccharide such as agarose or hydroxyethyl cellulose, in a suitable solvent, such as water; adding a cross-linking agent, which is not charged nor becomes charged upon contact with water in a pH range of 2 to 11, to the solution; and incubating this mixture in a quiescent state to substantially simultaneously react the polysaccharide and the cross-linking agent and to gel the reaction product into a bed. The polysaccharide is at least one linear polysaccharides, but that linear polysaccharide may also be admixed with other linear polysaccharides and/or at least one non-linear polysaccharide. Synthetic organic polymers may also be admixed in the cross-linking reaction mixture.

Abstract: The method of electrophoresis uses for separation of charged species their different mobilities in an electric field. The process is usually carried out by forcing the molecules to migrate through an aqueous gel. The gels are run in essentially two types of electrophoretic units: vertical and horizontal ones. It was found that in the standard submerged electrophoresis units the resolution of DNA in the poly(NAT) gels was never so good as in the vertical system. It was observed that by looking at the gel from above under an angle declined from the vertical, the viewed DNA bands in the gel were much sharper than they were pictured on the photograph taken by a camera positioned more or less vertically above the gel. On basis of this observation it was assumed that the diffuseness of bands seen on the photograph did not originate from a real diffuseness of bands in the gel, but rather from the vertical position of the camera and bending of the bands against the vertical axis.

Abstract: An acrylic monomer which is an amino sugar alcohol whose primary or secondary amino group has been derivatized by an acryloyl or a methacryloyl function. The amino group can be linked to any carbon of five or six-carbon sugar alcohols. The acrylic monomer has the formula: ##STR1## where R.sub.1 is H, CH.sub.2 OH or (CHOH).sub.m CH.sub.2 OH, m being 1 or 2;R.sub.2 is monohydroxyalkyl, polyhydroxyalkyl or hydrocarbon radical;R.sub.3 is H or CH.sub.3 ; andn is an integer of 1-4The acrylic monomer can be polymerized by a free radical polymerization, either alone or with other compounds and materials having polymerizable double bonds. The so formed polymers are linear or branched (cross-linked). The cross-linked polymers are usually in the form of gels. The gels can be polymerized in different forms and shapes, i.e., beads, thin sheets, rods, blocks, etc. and are useful as separation media, e.g.

Abstract: A bed of transparent, water insoluble, charge-free crosslinked gel which is suitable for use in electrophoresis is prepared. The gel is formed by dissolving a linear polysaccharide, such as agarose, in a suitable solvent, such as water. This dissolution may be accomplished with agitation. A suitable cross linking agent, which is not itself charged, nor does it become charged upon contact with water, at a pH of 2 to 12, is then added to the solution, possibly with agitation in order to get thorough mixing of the linear polysaccharide and the cross linking agent. This mixture is then allowed to incubate and react in a quiescent state to substantially simultaneously gel and crosslink to form the desired cross linked gel bed. Preferred cross-linking agents are bis-epoxides, halo-epoxides, bis-haloalkanes, bis-halo-alcohols, alkanediol-bis-alkyl sulfonates, alkanediol-bis-aryl sulfonates or divinylsulfone. The liner polysaccharide maybe mixed with a synthetic polymer such as polyvinyl alcohol.

Abstract: A novel synthesis of N-acryloyl-tris-(hydroxymethyl)aminomethane (NAT) is described. The polymerization kinetics and transparency of the poly(NAT) gels crosslinked by a crosslinker (CL) e.g. N,N'-methylenebisacrylamide (Bis), i.e. poly(NAT+Bis) polymer, are shown. Poly(NAT+Bis) gradient (4-24%) gels were prepared and found to resolve native proteins according to their size. The exclusion limit of these gels is over 3.times.10.sup.6 Da. This is more than threefold higher than the exclusion limit of the polyacrylamide gradient gel of the same concentration. Therefore poly(NAT+CL) gels are better than polyacrylamide gels for the resolution of large proteins. It was demonstrated that poly(NAT+CL)-polyacrylamide composite gels could be prepared. The poly(NAT+CL) gels were found to be advantageous also for isoelectric focussing in carrier ampholytes or immobilized pH gradients. Poly(NAT+CL) gels are also very good for separation of nucleic acids.

Abstract: A method for detecting a glycoprotein using a solid support is disclosed where the glycoprotein is oxidized by periodate, polyacrylic polyhydrazide which is a copolymer having repeating units possessing a hydrazide group and repeating units possessing hydroxyl groups is coupled to the oxidized glycoprotein and a glycoenzyme or radioactive compound containing aldehyde groups or activated ketone groups is coupled to the polyacrylic polyhydrazide which allows for detection of the glycoprotein. The glycoprotein may be directly attached to the solid support or may be bound to an antigen which is immobilized on the solid support.

Abstract: An acrylic monomer which is an amino sugar alcohol whose primary or secondary amino group has been derivatized by an acryloyl or a methacryloyl function. The amino group can be linked to any carbon of five or six-carbon sugar alcohols. The acrylic monomer has the formula: ##STR1## where R.sub.1 is H, CH.sub.2 OH or (CHOH).sub.m CH.sub.2 OH, m being 1 or 2;R.sub.2 is monohydroxyalkyl, polyhydroxyalkyl or hydrocarbon radical;R.sub.3 is H or CH.sub.3 ; andn is an integer of 1-4The acrylic monomer can be polymerized by a free radical polymerization, either alone or with other compounds and materials having polymerizable double bonds. The so formed polymers are linear or branched (cross-linked). The cross-linked polymers are usually in the form of gels. The gels can be polymerized in different forms and shapes, i.e., beads, thin sheets, rods, blocks, etc. and are useful as separation media, e.g.

Abstract: Electrophoresis apparatus for conducting electrophoresis in submerged gels, comprises a plurality of compartments including at least one gel compartment and at least one reservoir compartment; a plate as the bottom of a gel compartment, electrodes only in a gel compartment; the electrodes arranged in such a way that during operation the created electric field is confined essentially within a rectangular box, the said rectangular box defined on sides by side walls or barriers, on top by air and on bottom by the plate; means to circulate buffer; and barriers in a gel compartment mounted on the plate in front of buffer circulation openings.

Abstract: A process for the preparation of stabilized glycoproteins without the introduction of foreign molecules. Susceptible monosaccharides covalently attached to the protein part of the molecule undergo periodate oxidation and, after elimination of the remaining periodate, the oxidized glycoprotein is incubated in a buffer under conditions favorable for the reaction between the aldehyde groups generated in the sugar part and the amino acid residues from the protein part. The oxidized carbohydrate chains act as a polyaldehyde crosslinker, with the cross-linking reaction producing intramolecularly and intermolecularly linked derivatives. The amount and size of the intermolecularly linked derivatives are controlled by degree of oxidation and protein concentration. The thermal stability, depends on the degree of oxidation and under optimal conditions is about 10 times better than the stability of native invertase.