A portable array biosensor

An array biosensor developed for performing simultaneous analysis of multiple samples for multiple analytes has been miniaturized and fully automated. The biochemical component of the multi-analyte biosensor consists of a patterned array of biological recognition elements ("capture" antibodies) immobilized on the surface of a planar waveguide. A fluorescence assay is performed on the patterned surface, yielding an array of fluorescent spots. the locations of which are used to identify what analyte is present. Signal transduction is accomplished by means of a diode laser for fluorescence excitation. optical filters and a CCD camera for image capture. A laptop computer controls the miniaturized fluidics system and image capture. Data analysis software has been developed to locate each spot and quantify the fluorescent signal in each spot. The array biosensor is capable of detecting a variety of analytes including toxins, bacteria and viruses and shows minimal interference from complex physiological sample matrices such whole blood and blood components, fecal matter, saliva, nasal secretions, and urine. Some results from recent field trials are presented.