The array biosensor was fabricated to analyze multiple samples simultaneous
ly for multiple analytes. The sensor utilized a standard sandwich immunoass
ay format: Antigen-specific "capture" antibodies were immobilized in a patt
erned array on the surface of a planar waveguide and bound analyte was subs
equently detected using fluorescent tracer antibodies. This study describes
the analysis of 126 blind samples for the presence of three distinct class
es of analytes. To address potential complications arising from using a mix
ture of tracer antibodies in the multianalyte assay, three single-analyte a
ssays were run in parallel with a multianalyte assay. Mixtures of analytes
were also assayed to demonstrate the sensor's ability to detect more than a
single species at a time. The array sensor was capable of detecting viral,
bacterial, and protein analytes using a facile 14-min assay with sensitivi
ty levels approaching those of standard ELISA methods. Limits of detection
for Bacillus globigii, MS2 bacteriophage, and staphylococcal enterotoxin B
(SEB) were 10(5) cfu/mL, 10(7) pfu/mL, and 10 ng/mL, respectively, The arra
y biosensor also analyzed multiple samples simultaneously and detected mixt
ures of the different types of analytes in the multianalyte format.