title: Ionic liquids extraction of Para Red and Sudan dyes from chilli powder, chilli oil and food additive combined with high performance liquid chromatography.
abstract: A simple analytical method, based on the coupling of ionic liquid-based extraction with high performance liquid chromatography (HPLC), is developed for the determination of Sudan dyes (I, II, III and IV) and Para Red in chilli powder, chilli oil and food additive samples. Two ionic liquids (ILs), 1-butyl-3-methylimidazolium hexafluorophosphate ([C(4)mim][PF(6)]) and 1-octyl-3-methylimidazolium hexafluorophosphate ([C(8)mim][PF(6)]), were compared as extraction solvents; experiments indicated that the latter possesses higher recoveries for each analyte. Parameters related to extraction of Sudan dyes and Para Red were also optimized. Under the optimal conditions, good reproducibility of extraction performance was obtained, with the relative standard deviation (RSD) values ranging from 2.0% to 3.5%. The detection limits of Sudan dyes and Para Red (LOD, S/N=3) were in the range of 7.0-8.2 microg kg(-1) for chilli powder and 11.2-13.2 microg L(-1) for chilli oil and food additive. The recoveries were in the range of 76.8-109.5% for chilli powder samples and 70.7-107.8% for chilli oil and food additive samples.
authors.affiliation: Department of Chemistry, Xixi Campus, Zhejiang University, Hangzhou 310028, China.
authors.forename: Yunchang
authors.initials: Y
authors.lastname: Fan
authors.forename: Meilan
authors.initials: M
authors.lastname: Chen
authors.forename: Chao
authors.initials: C
authors.lastname: Shentu
authors.forename: Fawzi
authors.initials: F
authors.lastname: El-Sepai
authors.forename: Kaixiong
authors.initials: K
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhu
authors.forename: Mingli
authors.initials: M
authors.lastname: Ye