Assay device with a barrier for regulating reagent application

• Main Author: HOWARD M CHANDLER
• Format: Patent
• Language: English
• Published: 27.06.1995
• Edition: 6
• Subjects: CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PHYSICS; TESTING; TRANSPORTING

An assay device for detection and/or determination of an analyte in a test sample uses a barrier containing an aperture to control the application of reagents to the device for greater reproducibility of results. In its simplest form, the device comprises: (1) a chromatographic medium having a first end, a second end, and first and second surfaces, and having a specific binding partner for the analyte immobilized thereto in a detection zone; (2) at least one absorber in operable contact with at least one of the first and second ends; and (3) a substantially fluid-impermeable barrier adjacent to the first surface of the chromatographic medium, the barrier having at least one aperture therethrough for application of liquid to the chromatographic medium, the barrier at least partially blocking application of liquid to the chromatographic medium. The device can be adapted for sandwich or competitive assays and can be used to perform amplified assays, such as those using silver amplification or enzyme amplification. Various arrangements of components within the device are possible, and elements such as filters can be accommodated.