title: Detection of structurally similar adulterants in botanical dietary supplements by thin-layer chromatography and surface enhanced Raman spectroscopy combined with two-dimensional correlation spectroscopy.
abstract: Thin-layer chromatography (TLC) coupled with surface enhanced Raman spectroscopy (SERS) has been widely used for the study of various complex systems, especially for the detection of adulterants in botanical dietary supplements (BDS). However, this method is not sufficient to distinguish structurally similar adulterants in BDS since the analogs have highly similar chromatographic and/or spectroscopic behaviors. Taking into account the fact that higher cost and more time will be required for comprehensive chromatographic separation, more efforts with respect to spectroscopy are now focused on analyzing the overlapped SERS peaks. In this paper, the combination of a TLC-SERS method with two-dimensional correlation spectroscopy (2DCOS), with duration of exposure to laser as the perturbation, is applied to solve this problem. Besides the usual advantages of the TLC-SERS method, such as its simplicity, rapidness, and sensitivity, more advantages are presented here, such as enhanced selectivity and good reproducibility, which are obtained by 2DCOS. Two chemicals with similar structures are successfully differentiated from the complex BDS matrices. The study provides a more accurate qualitative screening method for detection of BDS with adulterants, and offers a new universal approach for the analysis of highly overlapped SERS peaks.
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Shanghai, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Pharmacy, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Qing xia
authors.initials: Qx
authors.lastname: Zhu
authors.affiliation: Institute of High Performance Computing, Agency for Science, Research and Technology (A*STAR), 1 Fusionopolis Way, Singapore 138632, Singapore.
authors.forename: Tsz sian
authors.initials: Ts
authors.lastname: Chwee
authors.affiliation: Institute of High Performance Computing, Agency for Science, Research and Technology (A*STAR), 1 Fusionopolis Way, Singapore 138632, Singapore.
authors.forename: Lin
authors.initials: L
authors.lastname: Wu
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Shanghai, China.
authors.forename: Yi feng
authors.initials: Yf
authors.lastname: Chai
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Shanghai, China. Electronic address: fenglufeng@hotmail.com.
authors.forename: Feng
authors.initials: F
authors.lastname: Lu
authors.affiliation: Department of Pharmacy, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. Electronic address: nmxyyf@126.com.
authors.forename: Yong fang
authors.initials: Yf
authors.lastname: Yuan
mesh_terms: D002855:Chromatography, Thin Layer / Q000379:methods*; D003102:Colloids / Q000737:chemistry; D019587:Dietary Supplements / Q000032:analysis*; D004340:Drug Contamination; D007004:Hypoglycemic Agents / Q000032:analysis; D007834:Lasers; D000077205:Pioglitazone; D015203:Reproducibility of Results; D000077154:Rosiglitazone; D012834:Silver / Q000737:chemistry; D013059:Spectrum Analysis, Raman / Q000379:methods*; D045162:Thiazolidinediones / Q000032:analysis
chemical_list: D003102:Colloids; D007004:Hypoglycemic Agents; D045162:Thiazolidinediones; D000077154:Rosiglitazone; D012834:Silver; D000077205:Pioglitazone
keywords: Duration of exposure to laser; Enhanced selectivity; Highly overlapped peaks; Structurally similar adulterants; Surface enhanced Raman spectroscopy; Two-dimensional correlation spectroscopy