Abstract: A electrophoresis column having on-column means and a method for concentrating analytes of interest in a sample prior to electrophoresis. The column comprises a section having the concentrating means upstream of a capillary section. A sample is flowed past the concentrating means which immobilizes the analytes of interest thereby concentrating the analytes of interest in the section. Thereafter the analytes are released from the concentrating means for carrying out electrophoresis.

Abstract: A specimen collection device including a sheet of flexible material and two generally parallel slits formed near opposite edges of the sheet. This sheet is preferably rectangular and is of sufficient dimensions such that the slits may receive a conventional toilet seat to suspend a central portion of the device under the seat within a toilet bowl. The central portion is adapted to receive a fecal specimen and the device and specimen may be easily disposed of.

Abstract: The filling of an internally coated capillary with a gel in its polymerized state without damaging the gel. The coating prevents bonding of the gel to the inside of the capillary. The gel comprises up to 6% acrylamide and 0-5% crosslinker. The gel can be advantageously and conveniently used in automated electrophoresis systems for automatic replacement of spent gel.

Abstract: Method for substituting a substitution compound for the hydrogen of a support bound primary hydroxyl group. The support bound primary hydroxyl group is treated in an organic, substantially anhydrous solvent in the presence of a tertiary amine base and the substitution compound.The substitution compound has a positive moiety and a negative moiety. The positive moiety is selected from the group consisting of trityl, pixyl, and derivatives thereof.The reagent is selected from the group consisting of tetraalkylammonium salts, inorganic salts, and mixtures thereof. Each reagent has a cation and an anion moiety.The cation moiety of the reagent is more electropositive than the positive moiety of the substitution compound. This relationship enables the reagent to attract the negative moiety of the substitution compound.

Abstract: An extraction vial includes a reservoir portion having generally parallel walls, a neck portion defining an opening into the reservoir portion and a channel surrounding the opening, a nozzle portion integral with reservoir portion at a second end of the reservoir, a sealing closure that closes the nozzle, a base integral with the sealing closure and including a support surface adapted to support the vial in an upright position, and a cap received and removably maintained within the channel. An extraction liquid may be contained within the vial for extracting sample from a carrier. The vial may be used by adding the carrier to the extraction liquid within the vial, closing the vial with the cap, agitating the vial to release sample from the carrier, and removing at least the sealing closure or, preferably, the sealing closure and base whereby extraction liquid can be expelled from the vial.

Abstract: Detecting light in a capillary electrophoresis optical system includes input and output windows in the outside surface of a capillary tube. The width of the windows is not substantially greater than the bore of the tube. A fiber optic input is spaced from the capillary tube so that the light is directed to the tube and is matched to the window width. The light output from the tube is matched to be received by a fiber optic output spaced from the capillary tube. The optical light envelop from the fiber input through the tube and to the fiber output is governed by the LaGrange Invariant. The matching is effected in accordance with the Numerical Aperture of the fiber optics.

Abstract: Ionic species and method for the quantitation of sample constituents utilizing capillary zone electrophoresis analysis are disclosed. As disclosed, at least one ionic species having a charge density of betwen about 0.02 and about 0.001 is added to the sample. Benzoic acid is a preferred ionic species. Quantitation of a sample constituent can be derived by normalizing the constituent species with the ionic species.

Abstract: Improved fecal occult blood test having a matrix such as paper printed or impregnated with guaiac. The improvement comprises increasing the sensitivity while maintaining or improving the specificity of the test by employing an alcoholic peroxide developing solution which contains an enhancing agent. The enhancers comprise phenolic type compounds such as esters of parahydroxybenzoic acids.

Abstract: Disclosed herein is a liquid scintillation solution useful for alpha particle emission and beta particle emission discrimination. Most preferably, the liquid scintillation solution comprises at least one naphthalene derivative enhancing agent; at least one solvent; and at least one fluor. In a particularly preferred embodiment, the liquid scintillation solution comprises di-isopropyl naphthalene as the enhancing agent; phenylxylethane as the solvent; and 2-(4'-biphenyl)-6-phenylbenzoxazote as the fluor.

Abstract: A capillary electrophoresis detector assembly including a separation column in which the components of a mixed sample are separated; an exit column which completes the connection to the terminal buffer reservoir; and a support sleeve which includes precisely positioned radial bores therethrough to allow insertion of optical fibers in the form of an input fiber which transmits the incoming radiation from an illumination source and an exit fiber which receives the radiation and relays same to a detector.In fabricating the assembly, a precision wire is partially inserted into the output end of the separation column. The column/wire combination is inserted into one end of the sleeve. The exit column is threaded onto the precision wire and also inserted into the opposite end of the sleeve. The input and exit fibers are inserted into the radial bores in the sleeve until they touch the precision wire in opposition.

Abstract: A method is provided for determining the sequence of nucleotides on a single strand DNA molecule. The single strand DNA molecule is attached to a leader oligonucleotide and its complementary strand to a solid state support. Fluorescently-labeled 3'-blocked nucleotide triphosphates, with each of the bases A, G, C, T having a different fluorescent label, are mixed with the bound DNA molecule in the presence of DNA polymerase. The DNA polymerase causes selective addition of only the complementary labeled NTP, thus identifying the next unpaired base in the unknown DNA strand. The 3'-blocking group is then removed, setting the system up for the next NTP addition and so on. The sequence is repeated until no more fluorescently-labeled NTPs can be detected as being added by the polymerase.

Abstract: A system for analyzing a chemical reaction provides control of the temperature and volume of the reagents to improve the accuracy and precision in quantitative measurements of specific proteins and other immunochemistries in body fluids. The reaction occurs in a cuvette within a nephelometric optics module. A sensor senses the temperatures of reaction buffer liquids as they flow into the cuvette, and a heat exchanging device increases or decreases the temperatures of the buffer liquids. A control circuit responsive to the temperature sensor controls the heat exchanging device to maintain the temperature of the buffer liquids and the cuvette within a selected temperature range. The system may also include a sample pickup station, a sample probe for withdrawing a selected sample from the sample pickup station, a sample preparation station, and transport device for carrying said sample from the sample preparation station to the reaction cuvette.

Abstract: The present invention is directed to a technique that provides enhanced separation resolution in electrophoresis. This technique involves the use of a time-varying field strength, which may be progressively increasing or decreasing, constant or otherwise, as a function of time. The shape of the field strength with respect to time may be continuous or stepwise over time, monotonic or otherwise.Because the mobility of different size species is a function of the applied electric field, the use of a nonuniform (time varying) electric field increases the resolving power of electrophoresis. This technique has been found to provide enhanced resolution of double-stranded DNA molecules in capillary polyacrylamide gel electrophoresis. It has been found that enhanced separation of DNA restriction fragments of 1 to more than 1000 base pairs in size has been achieved employing the technique of the present invention.

Abstract: A salt bridge for a flow cell which includes a porous bridge element between fluid flow in the flow cell and in an internal reference fluid flow. The bridge element is surrounded by a body with a bore into which different tubes are located about the porous element. A cylindrical anchoring tube adjacent one end of the body is screw threaded into an aperture in the wall of the flow cell so that self-alignment of the salt bridge in the flow cell is effected. The salt bridge provides a conductivity path between the two flow paths without introducing another potential.

Abstract: Focusing a generated radiation signal on a detector is effected by a curvilinear surface. The radiation beam signal from the reflected surface is collimated or focused on the detector. Light scattered, Raman scattered, fluorescence, chemiluminescence, phosphorescence radiation signals from particles as a result of a chemical procedure or reaction is enhanced through this focusing technique. The enhanced signal which is detected is subsequently measured through different detection techniques.

Abstract: An indirect potentiometric method and diluent for the analysis of lithium are disclosed. The diluent includes effective amounts of a pH buffer and a non-cationic surfactant comprising at least one hydrophobic group, at least one hydrophillic group and being substantially free of polyoxyethylene groups. Most preferably, the pH buffer is tris-(hydroxymethyl) aminomethane-phosphate, and the surfactant is 2, 4, 7, 9-tetramethyl-5-decyn-4,7 diol. An indirect potentiometric determination of lithium in a clinical sample comprises the steps of mixing the sample with a diluent, contacting an aliquot of the diluted sample with a lithium specific ion selective electrode and at least one ion selective elctrode specifically responsive to a monovalent interfering ion, and measuring both the response of the lithium specific ion selective electrode and the monovalent interfering ion specific ion selective electrode, the responses being an indication of the concentration of lithium in the sample.

Abstract: A method and apparatus for generating scintillation pulse height distribution spectrum with respect to a square root representation of pulse height. Pulse height data are pooled into variable size windows of which the average energy level is approximately proportional to the square of the corresponding window number. The square root representation is accomplished by choosing the size of each window according to an arithmetic series of a constant difference between windows.

Abstract: An improved solid-state ion-selective electrode has greater uniformity of asymmetric potential and high sensitivity and selectivity for the cation of interest. The electrode comprises: (1) a porous element comprising graphite; (2) an electrochemical reference in substantially dry form on at least a portion of the element, the reference comprising: (a) an oxidant and (b) a reductant that is the conjugate of the oxidant, the oxidant and reductant being present in about equimolar quantities; and (3) a polymeric membrane comprising an ion-selective ionophore in electrochemical contact with the electrochemical reference. The electrode can be prepared to be selective for one of a number of cations, including lithium and ammonium. Methods for preparing these electrodes are also disclosed.

Abstract: A reciprocating fluid pump having a shaft which dynamically self-corrects angular misalignment between the shaft and its drive mechanism during reciprocative motions. A thrust bearing is utilized to take up axial loading of the shaft to allow the shaft to freely rotate on its supports.

Abstract: The present invention provides processes for isoelectric focusing ("IEF") and associated detection, which incorporates a dynamic means of electroosmotic flow ("EOF") control during IEF and/or after IEF to effect solute mobilization. In accordance with the present invention, the EOF control during IEF and/or solute mobilization after IEF are accomplished by applying an external electric field, relative to an internal electric field, to modify the electroosmotic flow in the capillary. This can be done by disposing a conductive member at one or more locations outside and along the buffer column in the capillary. The conductive member may be statically charged or caused to conduct a current to create the external required electric field. The applied external electric field may be adjusted, relative to the internal electric field, during IEF as necessary to reduce or completely suppress EOF to prevent flow of the buffer.