Immunological cross-reactivity of Naja sumatrana venom toxins by indirect ELISA and double-sandwich ELISA.

For indirect ELISA, the immunoplate was coated with 100 ng/ml of the venom toxin as antigen, and reacted with anti-PLA2IgG, anti-NTX IgG and anti-CTX IgG (dilution of 1∶200), respectively. For double-sandwich ELISA, the immunoplate was coated with 4 µg/ml of anti-PLA2 IgG, anti-NTX IgG and anti-CTX IgG respectively; and subsequently incubated with 100 ng/ml of venom toxin.The venom toxins used were phospholipase A2 (PLA2), neurotoxin (NTX) and cardiotoxin (CTX). Data were expressed as mean ± S.D. for n = 3.