Abstract: A bufferless electrophoresis system for separation of DNA or the like includes a disposable cassette comprising a housing having open ends, a three dimensional gel body in the housing for defining a path, a sample well in a top surface of the gel for introducing a sample into the path at one end thereof, an electrically conductive film closing the ends of the housing and contacting the ends of the gel, and an electrical circuit for selectively applying an electrical potential via the electrically conductive film to the ends of the gel. A holder having spaced apart opposed terminals may be used to hold the cassette and apply the electrical circuit to the cassette.

Abstract: A method of preparing a microcapillary gel separation column for electrophoresis comprises: pretreatment of a tube with a bifunctional reagent to provide polymer bonding sites on the inner wall of the tube; filling the tube with a monomer solution a cross-linking agent, and a photoinitiator; forming a polymer plug by illuminating an initiation section of the tube; growing the plug by moving the tube gradually past the illumination source; and stopping tube motion when the desired length of gal is attained. Provision is made for monitoring polymerization and adjusting tube movement speed to avoid gaps in the growing polymer.

Abstract: Electroporation of prokaryotic cells is achieved by the application of high-intensity electric fields of short duration to reversibly permeabilize the cell walls. Preferably, the field strength of the applied will be at least about 5 kV/cm and the duration of the exposure will be in the range from 2 to 20 msec. Macromolecules may be introduced to the cells or obtained from the cells during this period of cell wall permeability. Most commonly, the method will be utilized for transformation of the cells with nucleic acids. Very high transformation efficiencies in the range from 10.sup.9 to 10.sup.10 cells/.mu.g and transformation frequencies approaching 80% and above have been achieved.

Abstract: Both a method and apparatus for separating zirconium isotopes by balanced ion migration in a counterflowing electrolyte are disclosed herein. In the method of the invention, zirconium chloride is dissolved in a solution of HCl, and a voltage of between 2 and 50 volts is applied across the electrolyte to create a flow of zirconium ions toward the cathode, and a counterflow of chlorine ions toward the anode which is balanced such that the lighter weight isotopes of zirconium migrate toward the cathode while the heavier weight zirconium isotopes stay in the vicinity of the anode. The apparatus of the invention includes a polarizing assembly formed from a bundle of small diameter glass tubes aligned between the anode and the cathode. The internal shape of the tubes impedes kinetic agitation movement of the zirconium ions in all directions except in the direction between the anode and the cathode, thereby expediting the separation process.

Abstract: New synthesis and analysis procedures for novel crosslinked polyamines and ampholytes. Polyamines are crosslinked with tartaric acid ester, malonic acid ester, or polycarboxylic acid esters of the citric acid cycle. The resulting crosslinked polyamine may further react with other compounds such as an .alpha., .beta.-unsaturated or .alpha.-halo unsaturated carboxylic acids to prepare new ampholyte mixtures. The resulting novel ampholytes exhibit greater heterogeneity and complexity than presently prepared ampholytes, and can be used in analytical and preparative isoelectric focusing processes.Novel ampholyte analysis process entails analyzing chemical compounds, usually ampholytes, used in isoelectric focusing processes. The ampholyte is isoelectrically focused on an immobilized pH gradient, and then immersed in a picric acid solution to cGOVERNMENT OWNERSHIPThe funding for the subject matter described herein was partially provided by the U.S. Government under Grant Nos. NAS 9-17403 and NIH AI-20590. The U.S.

Abstract: An insulating film in a container has pores whose diameter is smaller than the diameter of a first type of cells in the container. The first type of cells are trapped in the pores, so that when an electric field is applied to the container, electroporation of the first type of cells occurs. If a second type of cells, smaller than the first type of cells, are also trapped in the pores, electrofusion will occur between the first and second types of cells trapped in the same pores.

Abstract: A technique for separating, identifying and measuring ions in solution by capillary zone electrophoresis is described, which provides improved sensitivity and resolution of anionic and cationic species. The method involves introducing a sample containing the ionic species into a narrow core capillary filled with a carrier electrolyte containing a selected light-absorbing anion or cation to an electrical current in a capillary column causing the ions to elute according to their ionic mobility. Both UV absorbing and UV-transparent ions can be detected and quantitated by UV/Visible photometric monitoring.

Abstract: A cell handling apparatus is provided with a device for moving cells which are held in chambers of the apparatus, at predetermined periods, preferably a device for generating pulse-like changes in fluid pressure of the chambers, so as to prevent the same portions of the cells from remaining in contact with the wall surfaces of the chambers over a predetermined period of time.

Abstract: The electrophoresis apparatus of the invention includes a semi-permeable element 6 which makes it possible to take advantage of the phenomenon of electro-endosmosis which is generated during electrophoresis, and outlet tube(s) 15 to transfer the products which emerge from the electrophoresis gel to the exterior by means of a buffer 9 which flows across the semi-permeable element in the direction opposite to that in which the products migrate.

Abstract: A capillary blotting sandwich for transferring soluble macromolecules in a liquid medium from a liquid-permeable matrix to a semi-permeable receiving membrane. The blotting sandwich includes: (i) a liquid-permeable matrix layer comprising soluble macromolecules, said matrix having at least one flat surface, (ii) a semi-permeable membrane sheet layer disposed on said flat surface; (iii) an interlocked hydrophilic absorbent fiber-containing material in the form of a non-woven absorbent felt sheet or pad layer disposed on said semi-permeable membrane, wherein said felt layer facilitates capillary transport of a solution through said membrane, whereby said soluble macromolecules in said matrix layer are caused to migrate to said membrane layer.

Abstract: A gel electrophoresis cassette is provided having two plates and two spacers between the plates. The spacers are positioned slightly inward of the plate edges to form small edge spaces. A soft adhesive is positioned within the small edge spaces and, subsequent to electrophoresis, the adhesive can be easily removed from the small spaces. The plates and separators then can be separated manually.

Abstract: A vertical gel electrophoresis apparatus featuring a support plate mounted in a buffer solution container, the support plate securing a gel assembly in position and dividing the container into two laterally juxtaposed isolated chambers. The support plate includes two vertical support members which are mounted along opposite vertical sides of the container, and an integral support member mounted along the bottom of the container. A face is cut in each vertical support member to receive opposite vertical edges of a gel assembly. The integral bottom support member includes a face terminating at flanges proximate the vertical support members. The bottom edge of the gel assembly rests on the flanges over the face of the integral bottom support member.

Abstract: The method of capillary electrophoresis of the present invention is carried out using an electrophoretic buffer containing an ungelled agarose polymer, wherein the agarose polymer concentration may be constant or may be changed on a time basis.The method of the present invention permits efficient fractional assay with high reproductibility. Particularly, the mode using the apparatus of the present invention in which the agarose polymer concentration is changed on a time basis is suitable for fractional assay of DNA and proteins of a wide range of size because an electrophoretic buffer having an ideal composition for separation is supplied constantly.

Abstract: Surfaces of silica-containing materials, such as the inner walls of silica capillaries, used in chromatographic, particularly electrophoretic, separations are coated with an organic polymer layer to reduce or eliminate surface charges. The layer is applied by first converting the silanol groups on the surface to silicon halide groups, then reacting these groups with an organometallic reagent having a terminal ethenyl moiety, preferably vinyl or allyl lithium or a vinyl or allyl magnesium halide, to convert the silicon halide groups to Si--R groups where the R retains the terminal ethenyl moiety, and finally reacting these ethenyl groups newly attached to the surface with a neutral organic monomer in an addition polymerization reaction to form a monomolecular noncrosslinked polymer layer over the surface. The resulting polymer layer is linked to the silica directly through a Si--C bond which is stable over a wide range of pH conditions.

Abstract: This invention relates to a detection method and apparatus useful in capillary electrophoresis and capillary chromatography that employs an array of solid state detector such as a charge-coupled device operating in the time-delayed integration mode which allows more exposure time of the moving analyte zones. The CCD is synchronized so that after a normal exposure of the CCD, the charge information in every row of the CCD is shifted toward one end of the CCD and the charge/signal information in the last row is quantified. Applying the CCD and the time-delayed integration method in effect increases the effective sampling volume of the flow cell without introducing band broadening. Use of the CCD as a fluorescence detection in capillary electrophoresis separations allows analytes to be differentiated both in migration time and fluorescence emission, yielding detection limits for fluorophores in the 1-8.times.10.sup.-20 mole range.

Abstract: Polyacrylamide gel filled silica capillaries of improved performance in electrophoresis are produced bya) leaching the capillary with a solution of a basic reagent;b) binding a substituted, double bond-containing silane to the silica surface of the capillary;c) binding an acrylamide to the treated surface and polymerizing the acrylamide to a linear polyacrylamide, eliminating electroosmotic flow and avoiding chemical bonding of the gel during its subsequent formation; andd) contacting the capillary with a solution of acrylamide/bisacrylamide and effecting crosslinking polymerization in the presence of a radical polymerization starter to form a gel.

Abstract: External markers and method for the identification of protein-and-peptide-containing samples utilizing capillary electrophoresis analysis. As disclosed, at least two external markers are added to the sample: one of the markers is a neutral charge species and one of the markers is an ionic species. Dimethylformamide is a preferred neutral charge species and benzoic acid is a preferred ionic species. Identification of constituent species is determined by comparing the migration ratios of the constituent species with migration ratios for each constituent species member.

Abstract: A horizontal electrophoresis assembly is described which is designed to utilize very thin gels of polyacrylamide. The assembly allows for water cooling of the gel during electrophoresis so that higher voltages can be applied to the gel without polymer degradation. The gel mold is made from a set of glass plates which are clamped into place defining a gel mold between them. In one embodiment, the site of field introduction is separated from the site of sample introduction so that the electric field is generally linear at the region of sample introduction.

Abstract: An electrode set for electrotransformation of a host cell by electroporation, comprising: an electrically insulating substrate; and at least one pair of interdigitated electrodes which are carried by said substrate and which lie in a generally planar array, said electrodes and said substrate being adopted to carry a cell transformant and a host cell thereon, said electrodes and said host cell and said cell transformant being adapted to pass electrical current upon the application of a potential difference across said electrodes.

Abstract: A method and compositions for separating molecules based on molecular size, shape, affinity, chirality, weight, charge, and hydrogen bonding, using a mosaic matrix formed by polymerizing a dispersion of dispersoids within a polymeric matrix. The dispersoids and matrix can be of the same or different hydrophobicity or hydrophilicity. The dispersoids can be porous or non-porous. The mosaic matrix can be used with existing chromatographic and electrophoresis apparatus to effect an enhanced separation of molecules, particularly of nucleic acids and peptides, by application of a solution and/or an electrical field to the matrix. The solution can form a pH, ionic, or composition gradient, and be applied using gravity or under pressure. The electrical field can be continuous, pulsed, or two-dimensional.