The determination of optical brighteners in laundry detergents by reverse phase and ion pair high performance liquid chromatography

Abstract

Abstract Eleven optical brighteners have been qualitatively and quantitatively determined using C 18 , C 8 , or C 2 reverse phase high performance liquid chromatography (HPLC) columns. Comparable results also were obtained using radially compressed reverse phase HPLC cartridges. Mobile phases consist of acetonitrile and methanol in water with 0.05 M phosphate buffer. Quaternary ammonium salts also are added to the mobile phase for ion pair formation. Ultraviolet (UV) detection at 340 nm gives more than adequate sensitivity for brighteners formulated between 0.05 and 2.0%. Sample preparation is simple and all components can be eluted within 15 min. Powdered and liquid detergents, fabric softeners, and bleach boosters have been routinely analyzed and results closely agree with those obtained using thin layer chromatography and densitometry.