Determination of preservatives in cosmetics and food samples by micellar liquid chromatography

✍ Scribed by Najma Memon; M. Iqbal Bhanger; M. Y. Khuhawer

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 193 KB
• Volume: 28
• Category: Article
• ISSN: 1615-9306
• DOI: 10.1002/jssc.200500060

✦ Synopsis

Abstract

An analytical procedure has been developed for the analysis of benzoic acid, p‐hydroxybenzoic acid, methyl‐, ethyl‐, propyl‐, isopropyl‐, and butyl esters of p‐hydroxybenzoic acid by micellar liquid chromatography. After dilution in n‐propanol the sample was directly injected onto a Lichrosorb ODS, 5 μm (250×4.6 mm ID) column and eluted with aqueous 2% Brij‐35 adjusted to pH 3.0 with phosphoric acid:propanol (80 : 20 v/v) at a flow rate of 1 mL min^–1^ and UV detection at 254 nm. A linear calibration curve was obtained simultaneously for each component in the range of 50–500 μg mL^–1^ for benzoic acid and 5–150 μg mL^–1^ for the other components; detection limits were within 25–250 ng mL^–1^ corresponding to125–1250 pg per injection (5 μL). The reproducibility in terms of average peak area and average retention time was obtained with coefficients of variation (CV) of 1.2% and 0.5%. The method was applied to analysis of these compounds in cosmetics (shampoos, hand lotions, creams, and bath foam) and food samples.