Solid-phase extraction of L-muscone from aqueous samples with Amberlite XAD-4 for gas chromatographic assay

An efficient analytical method was devised for the accurate L-muscone assay in aqueous samples. It involves solid-phase extraction of L-muscone in adsorption mode using XAD-4 as the sorbent and dichloromethane modified with 10% (v/v) methanol as the eluting solvent. The gas chromatographic analysis of the eluate residue dissolved in toluene on a DB-5MS capillary column provided complete resolution of L-muscone from the co-extracted interferences. The overall method showed excellent linearity (r2 > or = 0.9994) in the range of 0.1 to 2.0 microg/mL with good intra- and inter-day precisions (% RSD = 2.5 to approximately 7.3) and with high extraction recovery rates (> or = 98.1%). When the present method was applied to a L-muscone herbal drink product, the within-batch RE (%) in the labeled concentration (1.5 microg/mL) for the three randomly chosen bottles were -2.4, -1.3 and -3.3 with high precision (% RSD < or = 3.1). The present method is considered to be suitable for quality control evaluation on liquid drinks and other complex formulations fortified with L-muscone.