title: Two-dimensional correlation infrared spectroscopy applied to the identification of ephedrine and pseudoephedrine in illegally adulterated slimming herbal products.
abstract: Two-dimensional correlation spectroscopy (2DCOS) was employed for the identification of ephedrine (Ep) and pseudoephedrine (Ps) present in illegally adulterated slimming herbal products (SHPs). Second derivative (SD) spectral pretreatment was used prior to 2DCOS analysis to highlight specific features not readily observable by Fourier transform infrared spectroscopy (FTIR), SD-FTIR, or original 2DCOS, leading to enhanced resolution and a reduced lower limit of detection (<1% in this study). After examining the power spectra of suspicious SHPs, bands containing characteristic peaks for Ep (701, 747, 1042, 1363, 1375, 1451, 1478 cm-1etc) and/or Ps (703, 767, 1037, 1375, 1428, 1455, 1590 cm-1, etc.) were selected to construct synchronous and asynchronous maps for further analysis, while the latter was applied to discriminate positive SHPs adulterated simultaneously with Ep and Ps. The proposed method is simple and economical and has the potential to identify other chemicals in illegally adulterated herbal products. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Li
authors.initials: L
authors.lastname: Miao
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Yunpeng
authors.initials: Y
authors.lastname: Qi
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Lu
mesh_terms: D019440:Anti-Obesity Agents / Q000032:analysis*; D004340:Drug Contamination; D004809:Ephedrine / Q000032:analysis*; D014663:Nasal Decongestants / Q000032:analysis*; D010946:Plants, Medicinal / Q000737:chemistry*; D054199:Pseudoephedrine / Q000032:analysis*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D014662:Vasoconstrictor Agents / Q000032:analysis*
chemical_list: D019440:Anti-Obesity Agents; D014663:Nasal Decongestants; D014662:Vasoconstrictor Agents; D054199:Pseudoephedrine; D004809:Ephedrine
keywords: FTIR; ephedrine; pseudoephedrine; slimming herbal products; two-dimensional correlation spectroscopy