Use of Photogenerated Iodine for Sodium Thiosulfate Determination in Solutions for Injection

Abstract

A method for rapid determination of sodium thiosulfate in solution for injection that is based on titration of the active ingredient by photogenerated iodine is proposed. The titrant was produced by 1-2-min irradiation of an absorbing solution containing KI, acetate buffer, and eosin. The limits of detection (with errors of <3.0%) for sodium thiosulfate were 0.20 μg using current and 0.32 μg using the iodine-generation time in the absorbing solution. The time for a single determination of sodium thiosulfate could be reduced by using this method.