Directed-flow assay device
A diagnostic assay device that directs an applied sample to the analytical membrane of a directed flow device. The device has a sample receiving port defined by layers of built-up material on one end of the test strip. The port contains the sample and specifically directs it to the membrane in a controlled fashion. Additional features include configuration of the housing in a general C-shape with the test strip spanning the opening of the C-shape to allow access by a reader device. A preferred method employs superparamagnetic particles to label the target analytes for detection and measurement by means of an electromagnetic reader device.
1. A lateral flow assay device for quantitative detection of target analytes in a sample, said device comprising:
an assay support member having a first end and a second end;
a porous analytical membrane mounted adjacent to and generatly parallel with said support member, said analytical membrane having a first end and a second end and at least one capture region intermediate said first and second ends thereof, said at least one capture region being configured to capture labeled analytes moving from said first end of said analytical membrane toward said second end of said analytical membrane; and
a sample receiving port at one end of said support member for introduction into said device of the sample to be analyzed, said sample receiving port comprising:
a fluid sealing material on said support member;
a channel layer positioned above said sealing material, said channel layer comprising an opening and a channel, said opening providing fluid comunication with said channel, and said channel providing fluid communication with said porous analytical membrane;
a hydrophilic material positioned over said channel layer, said hydrophilic material having an opening therein corresponding to said opening in said channel layer; and
a gasket element positioned over said hydrophilic material and having an opening therein to allow fluid entry into the port, said gasket providing a fluid seal for the assay device.
2. The device recited in claim 1 , and further comprising a protective membrane covering said analytical membrane on the side opposite to said support member, said protective membrane being optically non-transparent.
3. The device recited in claim 2 , wherein said protective membrane is formed integrally with said porous membrane.
4. The device recited in claim 1 , and further comprising a control region in said porous membrane for collection of conjugates that have passed the capture region to show that said test strip has been used.
5. The device recited in claim 4 , and further comprising at least one magnetic calibration area printed on said protective membrane.