Quantification of Sunscreen Benzophenone-4 in Hair Shampoos by Hydrophilic Interactions Thin-Layer ChromatographyDensitometry or Derivative UV Spectrophotometry

Abstract EN

Benzophenone-4 (BZ4) was separated from surfactants, dyes, preservatives, and other components of hair shampoos by thin-layer chromatography on silica gel 60 stationary phase, with ethyl acetate-ethanol-water-pH 6 phosphate buffer (15 : 7 : 5 : 1 v/v/v/v) as mobile phase.

Densitometry scanning of chromatograms was performed at 285 nm.

The densitometric calibration curve for BZ4 was nonlinear (second-degree polynomial), with R>0.999.

The limits of detection and quantification were ca.

0.03 and ca.

0.1 μg spot−1, respectively.

The results obtained by HPTLC-densitometry were compared to those obtained by zero and 2nd derivative UV spectrophotometry.

In the case of spectrophotometric methods, calibration curves were linear with R>0.9998.

The chromatographic method was fully validated.