Richard Durst

US Patent:

53895231, Feb 14, 1995

Filed:

Jul 23, 1992

Appl. No.:

7/917426

Inventors:

Anne L. Plant - Arlington VA
Richard A. Durst - Clarksburg MD

Assignee:

The United States of Americas, as represented by the Secretary of
Commerce - Washington DC

International Classification:

G01N 33543
G01N 33544
G01N 33547
G01N 3508

US Classification:

435 792

Abstract:

A method of immunoanalysis combines immobilized immunochemistry with the technique of flow injection analysis, and employs microscopic spherical structures called liposomes, or lipid vesicles, as carriers of detectable reagents. Liposomes are modified on their surface with analytical reagents, and carry in their internal volume a very large number of fluorescent or electroactive molecules. Aspects of this embodiment of the invention include the chemistry for covalent immobilization of antibody fragments in a specified orientation, the use of liposomes in a flow injection analysis system, and the combination of automated sampling and analysis with reusable immunoreactants. Another aspect of the invention involves the non-covalent binding of liposomes to a receptor for use in a homogeneous assay. In another aspect of the invention the intensity of scattered light is quantitated as a measure of liposome aggregation in response to a concentration-dependent immunospecific reaction.