Analysis of nine food additives in wine by dispersive solid-phase extraction and reversed-phase high performance liquid chromatography

A novel and effective dispersive solid-phase extraction (dSPE) procedure using tetraethylenepentamine-functionalized Fe3O4 magnetic polymer (TEPA-MP) as an efficient adsorbent for cleaning up the matrix in wine was developed. Based on this, a simple and rapid analytical method for the simultaneous determination of nine food additives (i.e., acesulfame, saccharin, caffeine, aspartame, benzoic acid, sorbic acid, stevioside, dehydroacetic acid and neotame) in wine by reversed-phase high-performance liquid chromatography (RP-HPLC) with an ultraviolet (UV) detector was established. The results showed that the recoveries of the acidic food additives (pKa < 7.0) were highly dependent on the pH, and the TEPA-MP could be reused efficiently at least six times. Under optimized conditions, the recoveries for all analytes were between 80.1 and 97.1%, the intra-day RSDs were in the range of 1.7-8.5% and the inter-day RSDs were between 1.7 and 9.8%, and all the analytes had good linearities in the tested ranges with determination coefficients (r2) higher than 0.9991. The limits of quantification (LOQs) for the nine food additives were between 0.17 and 0.92 mg/L. The developed method was successfully applied to the wine samples, and it was confirmed that the TEPA-MP particles were highly effective dSPE materials.