Departmental Papers (MEAM)

Document Type

Journal Article

Date of this Version



Suggested Citation:
Changchun, Liu, et. al. (2009) A timer-actuated immunoassay cassette for detecting molecular markets in oral fluids. Lab on a Chip. Vol. 9(6). p. 768-776.

Reprinted by permission from The Royal Society of Chemistry (RSC). DOI: 10.1039/B814322F


An inexpensive, hand-held, point-of-care, disposable, self-contained immunoassay cassette comprised of air pouches for pumping, a metering chamber, reagents storage chambers, a mixer, and a lateral flow strip was designed, constructed, and tested. The assay was carried out in a consecutive flow format. The detection was facilitated with up-converting phosphor (UCP) reporter particles. The automated, timely pumping of the various reagents was driven by a spring-loaded timer. The utility of the cassette was demonstrated by detecting antibodies to HIV in saliva samples and further evaluated with a noncontagious, haptenized DNA assay. The cassette has several advantages over dip sticks such as sample preprocessing, integrated storage of reagents, and automated operation that reduces operator errors and training. The cassette and actuator described herein can readily be extended to detect biomarkers of other diseases in body fluids and other fluids at the point of care. The system is particularly suitable for resource-poor countries, where funds and trained personnel are in short supply.



Date Posted: 17 August 2010

This document has been peer reviewed.