Disposable unit in diagnostic assays

A diagnostic disposable device comprising:

• a housing;
• said housing comprising a top plate and a bottom plate fastened together, one plate having detents and the other plate having orifices for indexing said plates;
• said housing containing an assay system comprising:
• within said housing, a fluorescent lipid membrane;
• an incubation area in said housing, having opposing walls;
• a first wall supporting said fluorescent lipid membrane;
• a second wall supporting a reagent, said walls being spaced apart to provide for capillary flow through said incubation area, wherein said reagent specifically binds to a specific binding pair member proximal to one face of said fluorescent lipid membrane:
• proximal to one end of said housing, a sample port;
• a capillary channel connecting said incubation area to said sample port;
• reservoirs on each side of said incubation area, said side reservoirs being a reagent storage reservoir and a waste reservoir, and a main waste receiving reservoir downstream from said incubation area opposite from said channel, said main waste and side waste reservoirs having gas release ports, said side reagent storage reservoir having an inlet port, said gas release port being slots extending along one side of said reservoirs, wherein the side walls of said side reservoirs extending from said second wall drop steeply down to substantially reduce capillary force;
• and
• an optically clear window over said fluorescent lipid membrane.

A method for determining an analyte in a sample comprising:

• providing a disposable diagnostic device comprising:
• a housing;
• said housing containing an assay system comprising:
• an incubation area in said housing, having opposing walls;
• a first wall supporting a fluorescent lipid membrane having a first member of a specific binding pair of Which said analyte is a member proximal to an exposed surface of said membrane and a second wall supporting an enzyme conjugate reagent capable of binding to said first member in proportion to the amount of analyte in said sample, said walls being spaced apart to provide for capillary flow through said incubation area;
• proximal to one end of said housing a sample port;
• a capillary channel connecting said incubation area to said sample port;
• reservoirs on each side of said incubation area, said side reservoirs being a reagent storage reservoir for storing enzyme substrate and a waste reservoir, and a main waste receiving reservoir downstream from said incubation area opposite from said channel, said main waste and side waste reservoirs having gas release ports, side reagent storage reservoir having an inlet port;
• and
• an optically clear window over said fluorescent lipid membrane;
• adding sample to the sample port of said diagnostic device, whereby said sample is transported through the capillary channel into said incubation area;
• allowing said sample to move through said incubation area into a main waste reservoir downstream from said incubation area, whereby said enzyme conjugate is dissolved and specifically binds to the first members on said fluorescent lipid membrane in proportion to the amount of analyte present in said sample;
• introducing wash solution into said sample port, whereby said wash solution washes said incubation area substantially free of sample components and unbound enzyme conjugate;
• introducing a buffer solution into a side reagent storage reservoir to dissolve said enzyme substrate and transport said enzyme substrate through said incubation area into the side waste reservoir, whereby enzyme product is produced Which modulates the fluorescence of said fluorescent lipid membrane;
• irradiating said fluorescent lipid membrane through said optically clear window, whereby said lipid membrane is excited and fluoresces;
• and
• measuring the fluorescence intensity at at least one time to determine the presence of analyte in said sample.

A diagnostic disposable device comprising:

• a housing for use in an assay for determining an analyte;
• said housing containing a plurality of areas for providing different functions associated with said assay;
• an incubation area having spaced apart walls to provide for capillary flow through said incubation area;
• proximal to one end of said housing, a sample port;
• a capillary channel connecting said incubation area to said sample port;
• side reservoirs on each side of said incubation area, said side reservoirs being a reagent storage reservoir and a waste reservoir, and a main waste receiving reservoir downstream from said incubation area opposite from said channel, said main waste and side waste reservoirs having gas release ports, with said reagent storage reservoir having an inlet port to allow for flow of liquid orthogonal to the direction defined by said capillary channel;
• an optically clear window over said incubation area.