Bioassay (an analytical method to determine concentration or potency of a substance by its effect on living cells or tissues) guided fractionation and chromatography identified stromatoxin, a peptide consisting of 34 amino acids that belongs to the structural family of inhibitor cystine knot spider peptides, as the functional component.
A bioassay is an analytical method to determine concentration or potency of a substance by its effect on living cells or tissues. Fractionation is a separation process in which a certain quantity of a mixture (gas, solid, liquid, enzymes, suspension, or isotope) is divided during a phase transition, into a number of smaller quantities (fractions) in which the varies according to a gradient. Chromatography is a laboratory technique for the separation of a mixture. Stromatoxin is a spider toxin that blocks certain delayed-rectifier and A-type voltage-gated potassium channels. Stromatoxin is a peptide consisting of 34 amino acids that belongs to the structural family of 'inhibitor cystine knot' spider peptides. Bioassay guided fractionation and chromatography identified stromatoxin as the functional component. 
