Determination of fluorescent whitening agents in disposable sanitary products by high performance liquid chromatography

Abstract

A method for the determination of four fluorescent whitening agents (FWAs) (FWA 357, FWA 220, FWA 204 and FWA 113) in disposable sanitary products by high performance liquid chromatography with diode array detection (HPLC-DAD) was developed. The sample was extracted with a 20 mL ultrapure water by sonication for 30 min at 80 °C. The HPLC method was performed on an SB Phenyl column (250 mm x 4. 6 mm, 5 µm) by gradient elution using 5 mmol/L ammonium acetate and acetonitrile as mobile phases, which can separate the target analytes successfully. The target analytes showed good linearity in the range of 0. 025-400 mg/L with the correlation coefficients (r2) greater than 0. 999 9. The limits of detection (LODs, S/N =3) were 0.02-0. 1 mg/L, and the method limits of quantification (MLOQs) were 1. 0 - 5. 0 mg/kg for the target analytes. The feasibility of this method was demonstrated by the determination of FWAs in samples with spiked recoveries. The recoveries were in the range between 83. 7% and 101. 0%, and the relative standard deviations (RSDs) (n=6) ranged from 2. 4% to 7. 0%. This method is simple, and has high recoveries for the determination of FWAs in disposable sanitary products.