Development of a flow-through enzyme-linked immunosorbent assay and a dipstick assay for the rapid detection of the insecticide carbaryl

Membrane-based competitive enzyme immunoassays in flow-through and dipstick format for the rapid detection of carbaryl were developed. A nylon membrane was coated with anti-carbaryl antibody and a carbaryl-horseradish peroxidase (HRP) conjugate was used as the labeled antigen for competitive assay of carbaryl. Both tests had visual detection limits of 10 mu g L-1, sensitive enough to meet the requirements of regulatory agencies as a practical screening tool. Matrix interference was eliminated by appropriate dilution of sample extracts with buffer. With assay times of 5 min (flow-through) and 15 min (dipstick), these rapid tests can be useful as a quality control tool and can be used to qualitatively detect carbaryl. (c) 2004 Elsevier B.V. All rights reserved.