Rapid clinical diagnostics assays using injection-molded planar waveguides

The goal of our research program is to develop an evanescent wave immunoassay system that can be used in point-of-care and critical care settings. Several key attributes are required to accomplish this goal: (i) the assay system should be at least as sensitive as present day immunoassays; (ii) assay time should be 5 minutes or less; (iii) the assay protocol should be relatively simple; (iv) the sensor should be capable of performing more than one assay on a single specimen; (v) the assay system should be able to accommodate specimens such as serum, plasma and whole blood; and (vi) the sensor should be an inexpensive, disposable cartridge. Our laboratory has developed an injection-molded planar waveguide sensor that meets most, if not alt, of these attributes. This sensor has been evaluated in a number of different immunoassays for analytes such as bovine serum albumin, human chorionic gonadotrophin, creatine phosphokinase MB and cardiac troponin I.