Portable automatic sensor for toxic gases

Abstract

A method is provided for the integration of a low-volume liquid flow and ing system and a portable optical waveguide-based fluorescence detector for the chemical analysis of reagents in fluorescence-based reactions. The method is particularly applicable to the detection of enzyme inhibitors, modifiers, or ligands in cases where a fluorescent enzyme substrate or product exists. In a preferred embodiment, the presence and concentration of acetylcholinesterase inhibitors, such as chemical warfare nerve agents or certain insecticides, is determined by mixing aqueous samples with a dilute solution of n-methyl indoxyl acetate, and monitoring the formation of a fluorescent product (n-methyl indoxyl). The presence of an acetylcholinesterase inhibitor reduces the amount of fluorescent product formed in a given time period. The reaction product passes through a flow cell in which it is excited by the evanescent wave produced by light as the light undergoes total internal reflection within an optical rod or fiber, or by light coming out the end-face of an optical fiber or rod.

Dependencies are inferred from the claim text.