title: Rapid determination of trans-resveratrol in red wine by solid-phase microextraction with on-fiber derivatization and multidimensional gas chromatography-mass spectrometry.
abstract: There has been considerable public interest and a growing number of scientific studies linking certain phenolic compounds in grapes and wines, particularly trans-resveratrol (trans-3,5,4'-trihydroxystilbene, TRA), to human health benefits. Typical TRA concentrations in wine are very low. It is a polar compound with very low volatility, which makes it difficult to extract and to separate on a gas chromatography (GC) column without derivatization. In this study, a new method for trace analysis of TRA was developed using solid-phase microextraction (SPME) with on-fiber silylation derivatization. Multidimensional GC equipped with a heartcut valve and cryogenic focusing was coupled with a mass-selective detector and used for improved separations and analysis. The effects of SPME fiber selection, extraction time, temperature, and desorption time were investigated. The derivatization conditions, time/temperature and the volume of derivatization reagent were also optimized. The calibration curve was linear over the concentration range from 10 ng L(-1) to 5 mg L(-1), with a correlation coefficient of 0.9996. The average recovery of TRA in red wine was 83.6+/-5.6%. The method detection limit (MDL) for TRA in ethanol:water (12.5:87.5, v/v) solution in this study was 7.08 ng L(-1) whereas the MDL for TRA in pure water was 2.85 ng L(-1). The new method was used to test the TRA content in six selected Iowa red wine samples. Measured concentrations varied from 12.72 to 851.9 microg L(-1).
authors.affiliation: Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA 50011, USA.
authors.forename: Lingshuang
authors.initials: L
authors.lastname: Cai
authors.forename: Jacek A
authors.initials: JA
authors.lastname: Koziel
authors.forename: Murli
authors.initials: M
authors.lastname: Dharmadhikari
authors.forename: J
authors.initials: J
authors.lastname: Hans van Leeuwen
mesh_terms: D008401:Gas Chromatography-Mass Spectrometry / Q000295:instrumentation / Q000379:methods*; D016014:Linear Models; D015203:Reproducibility of Results; D000077185:Resveratrol; D012680:Sensitivity and Specificity; D052617:Solid Phase Microextraction / Q000379:methods*; D013237:Stereoisomerism; D013267:Stilbenes / Q000032:analysis*; D013696:Temperature; D013997:Time Factors; D014920:Wine / Q000032:analysis*
chemical_list: D013267:Stilbenes; D000077185:Resveratrol