An in vitro test for photoinduced toxicity of benzothiadiazine diuretics using bacteriophage lambda.

Abstract

Abstract— The relative photoinduced toxicity of five benzothiadiazine diuretics was assessed with respect to their potentiality to inactivate bacteriophage lambda by exposure to near‐UV light in a semi‐aqueous solution of 40% N,N‐dimethylformamide. The results showed the following order for the toxicity on a quantum yield basis: penflutizide > trichlormethiazide > methichlothiazide > benzylhydrochlorothiazide > hydrochlorothiazide. Since the bacteriophage was inactivated even when mixed with preirradiated solutions of the diuretics, some photoproducts are responsible for the photoinduced toxicity of the diuretics. Although a lowered pH affected the infectivity, it was a minor factor.