Sandwich enzyme-linked immunosorbent assay for Taiwan cobra venom

Poisonous snake bite victims usually have difficulty identifying the species, and clinical manifestations alone are not reliable because of overlapping symptoms. Thus, it is important to develop a quick and reliable mean of identifying the snake responsible. We describe the development of a sandwich-ELISA method for detection of venom in biological samples and apply it to a case of snakebite to confirm the clinical diagnosis. The sandwich-ELISA takes 6 h to complete. Cobra venom antigen gave positive absorbance at about 500 pg/ml. Good linearity with R2 values over 0.99 were observed in dilution series of 1:100 ng/mL of cobra venom in calf serum and human urine. A snakebite initially thought to be Trimeresurus mucrosquamatus was proven cobra with a serum venom level up to 288 ngmL 3 h after envenoming. Sandwich-ELISA provides a rapid and accurate method for clinical identification and evaluation of toxic antigens circulating in individuals bitten by the Taiwan cobra snake.