SIMULTANEOUS DETERMINATION OF P-HYDROXYBENZOIC ACID, 2-PHENOXYETHANOL, METHYL-P-HYDROXYBENZOATE, ETHYL-P-HYDROXYBENZOATE, PROPYL-P-HYDROXYBENZOATE, ISO-BUTYL-P-HYDROXYBENZOATE, AND N-BUTYL-P-HYDROXYBENZOATE IN SENSELLE LUBRICANT FORMULATION BY HPLC

Abstract

A new and simple reversed-phase high-performance liquid chromatographic (HPLC) method has been developed and validated for the simultaneous determination of p-hydroxybenzoic acid, 2-phenoxyethanol, methyl-p-hydroxybenzoate, ethyl-p-hydroxybenzoate, propyl-p-hydroxybenzoate, iso-butyl-p-hydroxybenzoate and n-butyl-p-hydroxybenzoate preservatives in senselle lubricant formulation. The seven compounds were separated on a C18 ChromSpher polymeric octadecylsilane (ODS)-encapsulated spherical silica column with acetonitrile-tetrahydrofuran-water, 22:14:64 (v/v/v) as mobile phase at flow rate of 1.5 mL/min. The analysis was performed with ultraviolet (UV) detection at 258 nm. The analysis time was <15 min. The method was validated with respect to linearity, precision, accuracy, selectivity, specificity, and limits of detection and quantitation. The calibration curves showed good linearity over the concentration range of 5.4–217 µg/mL. The correlation coefficients were ≥0.9996 in each case. The relative standard deviation (RSD) values for intra- and inter-day precision studies were <1%. The procedure describe here is simple, selective, and is suitable for routine quality control analysis and stability tests.