Automated fiber optic biosensor for multiplexed immunoassays

The multianalyte capability of the RAPTOR, a rapid, automatic, and portable fiber optic fluorimeter, was demonstrated. Employing evanescent wave illum ination an polystyrene fiber optic waveguides, the RAPTOR performed fluores cent immunoassays for Bacillus globigii spores, ovalbumin, Erwinia herbicol a, and MS2 coliphage. During a 4-day laboratory trial assaying 144 blind sa mples, the RAPTOR demonstrated detection of 10(5) cfu/mL B. globigii, 10(7) cfu/mL. E. herbicola, and 10(9) pfu/mL MS2; ovalbumin detection was less f avorable than expected due to sample degradation. Assays were completed in 10 min with no sample preprocessing. No false positives were identified. An tigen carryover between coupons was examined but was not found to elicit a notable response far any analytes, except B. globigii. Finally, assay resul ts obtained after reagent and waveguides had completed 30 negative (buffer) cycles were compared with standard assay results achieved with fresh reage nt and waveguides to determine whether antigen detection would decrease usi ng cycled reagent or optical probes. Detection efficacy proved to be unaffe cted by the use of cycled versus fresh probes or reagent.