title: Perchloric acid treatment of human blood for quantitative endotoxin assay using synthetic chromogenic substrate for horseshoe crab clotting enzyme.
abstract: A new reliable human blood treatment was established for quantitative endotoxin assay using synthetic chromogenic substrate [Boc-Leu-Gly-Arg-rho-nitroanilide]. Addition of perchloric acid in a final concentration of 1.25% to platelet-rich plasma or serum in a 2:1 volume ratio completely eliminated nonspecific amidase activities as well as inhibitors. By this method, the recovery of added endotoxin was nearly 100%, and was almost independent of sample dilutions and anticoagulants.
mesh_terms: D000581:Amidohydrolases / Q000378:metabolism; D000818:Animals; D002863:Chromogenic Compounds / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004731:Endotoxins / Q000097:blood*; D006801:Humans; D008033:Limulus Test; D009842:Oligopeptides / Q000494:pharmacology; D010472:Perchlorates / Q000494:pharmacology*
chemical_list: D002863:Chromogenic Compounds; D004731:Endotoxins; D009842:Oligopeptides; D010472:Perchlorates; C035732:butyloxycarbonyl-leucyl-glycyl-arginine-4-nitroanilide; D000581:Amidohydrolases