Beckman Instruments, Inc.

Beckman Coulter, Inc.

Fu-Tai A Chen

James C Sternberg

Gerald L Klein

Cheng-Ming Liu

Ramon A Evangelista

Chan S Oh

Ming-Sun Liu

Hann-Ping Wang

You-Zung Hsieh

Gene G Y Shen

You-Zung Hseih

The separation of enantiomeric pairs of compounds by capillary electrophoresis using highly sulfated &agr;-, &bgr;-, and &ggr;-cyclodextrins as chiral selectors is described herein. These charged cyclodextrins have a higher degree of sulfation and narrower heterogeneity than previous cyclodextrin derivatives. CE analyses using highly sulfated cyclodextrins produce improved resolution of a wide variety of chiral drugs, particulaly neutral compounds and amines. The highly sulfated &agr;-,&bgr;-, and &ggr;-cyclodextrins produce separations which complement each other to further expand the number of neutral and basic drugs that can be resolved by capillary electrophorsis.

Chiral separation of pharmaceutical compounds with charged cyclodextrins using capillary electrophoresis

Homogeneous competitive immunoassay methods for simultaneously detecting analytes using capillary electrophoresis and fluorescent detection systems are described. The methods are useful for detecting and/or quantitating the concentration of a plurality of drugs of abuse in a single urine sample using a single assay method.

Simultaneous analysis of analytes by immunoassay using capillary

A method for detecting an analyte in a sample uses both the specificity of an enzymatic reaction and the separation power of capillary electrophoresis. In general, the method comprises: (1) subjecting a first aliquot of the sample to an analytical technique such as capillary electrophoresis, which generates a first output such as an electropherogram; (2) reacting a second aliquot of the sample in an enzyme-catalyzed reaction converting the analyte into a product, the product being detectable by the analytical technique; (3) subjecting the second aliquot to the analytical technique to generate a second output; (4) in the case of electrophoresis, measuring the absorbance of the first and second outputs (electropherograms) as a function of migration distance along the electropherogram at at least one wavelength at which either the analyte or the product absorbs to produce a first absorbance scan and a second absorbance scan; and (5) comparing the first absorbance scan with the second absorbance scan to detect the analyte. The reaction can involve a coenzyme and the analytical technique can be directed to the coenzyme. Alternatively, at least two enzymes can be used, the first enzyme generating a first product that is then acted upon by the second enzyme.

Analysis of analytes in biological fluids

Homogeneous immunoassays and enzyme-substrate assays which use capillary electrophoresis and fluoescent detection systems are described. The method is useful for detecting and/or quantitating the concentration of analytes in a sample.

Homogeneous immunoassays and enzyme based assays of analytes using

Processes for the electrophoretic analysis of monosaccharides and/or polysaccharides are disclosed. The processes generally first include providing a composition having derivatized mono and/or polysaccharide components which are monosaccharide and/or polysaccharide labelled with a fluorescing charged compound. Then introducing the composition into an electrophoretic medium and applying an electric field across the electrophoretic medium causes the derivatized monosaccharide and/or polysaccharide components to differentially migrate within the electrophoretic medium. Then detecting the derivatized monosaccharide and/or polysaccharide components is accomplished by laser exciting the derivatized monosaccharide and/or polysaccharide components and monitoring fluorescent emission of the derivatized monosaccharide and/or polysaccharide components. The processes provide extremely low detection limits of the labelled components.

Fluorescent labelled carbohydrates and their analysis

Disclosed herein are buffers and methodologies for the capillary zone electrophoretic analysis of hemoglobin and the variants of hemoglobin. In a particularly preferred embodiment, the buffer comprises at least about 100 mM of barbituric acid, derivatives of barbituric acid, combinations of barbituric acid and derivatives of barbituric acid, and combinations of the derivatives of barbituric acid, and has a pH of at least about 8.0.

Analysis of hemoglobin variants by capillary zone electrophoresis

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.

Quantitation of samples utilizing capillary electrophoresis

Disclosed herein is a methodology for analyzing isoenzymes using capillary zone electrophoresis ('CZE') techniques. Briefly, an isoenzyme-containing sample and a substrate capable of being catalyzed by said isoenzyme into a reaction product are introduced into a capillary column comprising a buffer. Most preferably, the buffer contains the substrate prior to introduction of the sample into such substrate-buffer. CZE separation techniques are applied to the column such that the isoenzymes are separated from each other into discrete zones. The separation techniques are terminated such that product is rapidly generated by the catalytic conversion of substrate by the isoenzymes, and accumulated, within each discrete zone, followed by detection of product. Information regarding the relative distribution of the isoenzymes can be derived from the relative distribution of the product.

Capillary zone electrophoretic analysis of isoenzymes

Disclosed herein is a dynamic coating buffer useful in the analysis of samples by open-tube capillary electrtophoretic methods using untreated fused silica capillary columns. The dynamic coating buffer comprises at least one agent having at least two dissociation constants, and high ionic strength characteristics, said agent having a molarity range of from about 0.2M and about 1.0M and a pH range of from between about 3.0 and 11.0. A particularly preferred dynamic coating buffer comprises 0.5M sodium phosphate.

Capillary electrophoresis buffer

Disclosed herein are methodologies for the Capillary Electrophoretic Immunosubtraction ('CEI') of samples. In a preferred embodiment, CEI of a sample comprising constituent parts to be separated comprises the steps of: (1) separating a first aliquot of the sample into constituent parts by capillary electrophoretic techniques, and detecting said parts; (2) admixing a second aliquot of said sample with at least one specific binding partner to a constituent of said sample, said specific binding partner capable of being substantially removed from said aliquot; (3) separating said second aliquot into constituent parts by capillary electrophoretic techniques and detecting said parts; and (4) comparing the separated constituent parts of step (3) with the separated constituent parts of step (1).

Analysis of samples by capillary electrophoretic immunosubtraction

Disclosed herein are buffers and methodologies for the capillary zone electrophoretic analysis of hemoglobin and the variants of hemoglobin. In a particularly preferred embodiment, the buffer comprises at least about 100 mM of barbituric acid, derivatives of barbituric acid, combinations of barbituric acid and the derivatives of barbituric acid, and combinations of the derivatives of barbituric acid, and has a pH of at least about 8.0.

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.

Identification of sample constituents utilizing capillary electrophoresis

Method and electrolyte buffer useful in the analysis of samples comprising glycoproteins by capillary zone electrophoresis. The buffer comprises at least one agent capable of complexing with sugar moieties of glycoproteins. The buffer preferably further comprises at least one pH modifier. An embodiment of the buffer comprises boric acid as the complexing agent and sodium hydroxide as the pH modifier.

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Brea, CA, United States of America

Fu-Tai A Chen