Use of HPLC to demonstrate variation of venom toxin composition in the Thailand cobra venoms Naja naja kaouthia and Naja naja siamensis.

The composition of the venoms of Naja naja kaouthia and Naja naja siamensis from different commercial sources has been investigated using both ion-exchange and reverse-phase high-pressure liquid chromatography (RP-HPLC) in order to investigate variation in toxin contents. The venoms contained identical major toxin components, although in different relative concentrations. The venom collected separately from the left and right glands of individual snakes were virtually the same as judged by RP-HPLC. The cytotoxin CT-II, which was previously only reported to be present in Naja naja siamensis venom, was detected in all the venoms investigated. Two long neurotoxin homologues have also been isolated.