Immunochemical and Mass Spectrometric Detection of Mustard Gas Adducts to DNA andProteins: Verification and Dosimetry of Exposure to Mustard Gas

摘要

The use of sulfur mustard and nerve agents in the Iran-Iraq conflict and thethreat of chemical warfare in the recent Gulf War have stressed the need of reliable methods to detect the nature and extent of poisoning with chemical warfare agents. In this context, we extend our initial investigations on immunochemical detection of sulfur mustard adducts to DNA and proteins. Furthermore, mass spectrometric detection methods are being developed as independent, highly sensitive techniques having an almost absolute specificity. A method was developed for analysis of N7-(2-hydroxyethylt hioethyl)-guanine (N7-HETE-Gua) in digested DNA, based upon HPLC with electrochemical detection, which is suitable for calibration of methods for adduct detection. An immunoslotblot assay was developed using monoclonal antibodies raised against this adduct which has a substantially lower detection limit and is less laborious than the competitive ELISA. With immunofluorescence microscopy the lower detection limit for the exposure of blood is 0.3 micrometer sulfur mustard which corresponds to 1 N7-HETE-Gua per 4x106 nucleotides. The procedure for the detection of N7-HETE-Gua in human skin was improved which resulted in a detection limit of a 15-s exposure to saturated sulfur mustard vapor corresponding to a Ct value of sulfur mustard of ca. 275 mg.min/m3 which is far below the level that would give blisters.