title: Automated microanalysis using magnetic beads with commercial capillary electrophoretic instrumentation.
abstract: The potential of a new microanalytical method using magnetic beads (MBs) and commercial capillary electrophoresis (CE) instrumentation for performing enzymatic and inhibition assays, as well as for analysis of biological molecules such as antigens, substrates, etc., has been explored. A small quantity of magnetic beads containing immobilized biomolecules was injected into a neutral hydrophilic-coated fused-silica capillary. The short plug (2-3 mm) of beads was held fixed by a magnet placed in the cartridge of the CE system, without the use of frits. The beads could be replaced after each run, eliminating the need to regenerate the solid support. Two protocols were used for analysis: sequential injection (SI) and SI followed by isotachophoretic (ITP) focusing. Alkaline phosphatase (AP) and HIV-protease were used to demonstrate the SI procedure for enzymatic and inhibition assays. The second protocol, SI/ITP, was employed to quantitate an antigen (mouse mAB) using antibodies (sheep IgG towards mouse AB) immobilized on the beads. The MB-CE method, requiring only femtomole (fmol) quantities of material, can potentially be employed in diagnostic and forensic assays, kinetic studies and searching for inhibitors, ligands, receptors, etc.
authors.affiliation: Barnett Institute, Northeastern University, Boston, MA 02115, USA.
authors.forename: L G
authors.initials: LG
authors.lastname: Rashkovetsky
authors.forename: Y V
authors.initials: YV
authors.lastname: Lyubarskaya
authors.forename: F
authors.initials: F
authors.lastname: Foret
authors.forename: D E
authors.initials: DE
authors.lastname: Hughes
authors.forename: B L
authors.initials: BL
authors.lastname: Karger
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000276:immunology; D019075:Electrophoresis, Capillary / Q000379:methods*; D004800:Enzymes, Immobilized / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D016333:HIV Protease / Q000032:analysis* / Q000737:chemistry; D017320:HIV Protease Inhibitors / Q000737:chemistry; D008280:Magnetics; D051379:Mice; D008863:Microspheres; D009994:Osmolar Concentration; D010436:Pepstatins / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D004800:Enzymes, Immobilized; D017320:HIV Protease Inhibitors; D010436:Pepstatins; C014195:Streptomyces pepsin inhibitor; D000469:Alkaline Phosphatase; D016333:HIV Protease