Fluorescent Receptor Binding Assay for Detecting Ciguatoxins in Fish
Fig 5
(A) RBA(F) 1:3 dilution series (% binding versus fish extract [g mL-1]) for different fish with 0.506 (open circle), 0.170 (open square), and < 0.100ppb (open triangle) C-CTX-1equivalents. Dilution curves of fish containing less than 0.500 ppb CTX do not reach 50% binding preventing accurate determination of the IC50 values. (B) RBA(F) 1:3 dilution curve of a fish containing >7.00 ppb P-CTX-3C equivalents illustrating that the IC50 values from extracts containing higher CTX concentrations can be estimated accurately. Ciguatoxin concentrations in the fish are estimated by dividing the IC50 for the ciguatoxin standard curve (g ciguatoxin mL-1) by the IC50 from the diluted fish extract (g fish extracted mL-1).