Development of sensitive immunoassays for the detection of the glucuronide conjugate of 3-phenoxybenzyl alcohol, a putative human urinary biomarker for pyrethroid exposure.
Pyrethroids are widely used in agriculture as insecticides. This study describes a sensitive enzyme-linked immunosorbent assay for the detection of the glucuronide conjugate of 3-phenoxybenzyl alcohol, a putative pyrethroid metabolite that may be used as a biomarker of exposure to pyrethroids. Four antisera were elicited against two different immunizing haptens. Antisera were characterized in combination with several coating haptens. The lowest IC50 value (0.5 ng/mL) was obtained with antiserum 1891 and 3-phenoxybenzoic acid-BSA conjugate as the coating antigen. Antiserum 1891 was highly selective for the target compound with an overall cross-reactivity of <0.3% to structurally related compounds. The assay sensitivity was negligibly affected by pH 4-9. A 5-fold improvement in IC50 was observed using a 10-fold concentrated phosphate-fuffered saline as the assay buffer. Compared to assays conducted in normal phosphate-fuffered saline, the maximal absorbance was almost identical. A good correlation (r 2 = 0.99 and 0.97 for urine samples A and B, respectively) was observed between spiked levels and the levels detected by the immunoassay.
Kim
Hee-Joo
HJ
Department of Entomology and UCD Cancer Research Center, University of California, Davis, California 95616, USA.
Ahn
Ki Chang
KC
Ma
Seung Jin
SJ
Gee
Shirley J
SJ
Hammock
Bruce D
BD
D001592:Benzyl Alcohols / Q000652:urine*; D015415:Biomarkers / Q000652:urine*; D004781:Environmental Exposure; D020719:Glucuronides / Q000652:urine*; D006241:Haptens; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007118:Immunoassay / Q000379:methods*; D011722:Pyrethrins; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D001592:Benzyl Alcohols; D015415:Biomarkers; D020719:Glucuronides; D006241:Haptens; D011722:Pyrethrins; C064809:3-phenoxybenzylalcohol