Two Spectrophotometric Methods for the Assay of Benzalkonium Chloride in Bandage Samples

Abstract

AbstractTwo rapid, direct, extraction‐free spectrophotometric procedures were developed for the determination of benzalkonium chloride. The procedures were based on the formation of mixed dye‐surfactant aggregates between eosine Y and benzalkonium chloride (Method A), or between eosine B and benzalkonium chloride (Method B) in Clark‐Lubs medium by measuring the increase in absorbance at 556 and 550 nm, respectively. Beer's law was obeyed in the concentration range of 0.5–12 and 0.5–12 μg mL−1 for benzalkonium chloride with good precision and accuracy, whose limits of detection were 0.1 μg mL−1 at 556 nm for Method A and 0.2 μg mL−1 at 550 nm for Method B, respectively. The proposed procedures were successfully applied to the assay of benzalkonium chloride in bandages. The analytical results of the real samples were in good agreement with those by HPLC.