title: Combined NIR/MIR analysis: a novel method for the classification of complex substances such as Illicium verum Hook. F. and its adulterants.
abstract: A novel combined near- and mid-infrared (NIR and MIR) spectroscopic method has been researched and developed for the analysis of complex substances such as the Traditional Chinese Medicine (TCM), Illicium verum Hook. F. (IVHF), and its noxious adulterant, Iuicium lanceolatum A.C. Smith (ILACS). Three types of spectral matrix were submitted for classification with the use of the linear discriminant analysis (LDA) method. The data were pretreated with either the successive projections algorithm (SPA) or the discrete wavelet transform (DWT) method. The SPA method performed somewhat better, principally because it required less spectral features for its pretreatment model. Thus, NIR or MIR matrix as well as the combined NIR/MIR one, were pretreated by the SPA method, and then analysed by LDA. This approach enabled the prediction and classification of the IVHF, ILACS and mixed samples. The MIR spectral data produced somewhat better classification rates than the NIR data. However, the best results were obtained from the combined NIR/MIR data matrix with 95-100% correct classifications for calibration, validation and prediction. Principal component analysis (PCA) of the three types of spectral data supported the results obtained with the LDA classification method.
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China; Department of Chemistry, Nanchang University, Nanchang 330031, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Chemistry, Nanchang University, Nanchang 330031, China.
authors.forename: Minghua
authors.initials: M
authors.lastname: Mei
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China; Department of Chemistry, Nanchang University, Nanchang 330031, China. Electronic address: ynni@ncu.edu.cn.
authors.forename: Yongnian
authors.initials: Y
authors.lastname: Ni
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, Brisbane 4001, Australia. Electronic address: s.kokot@qut.edu.au.
authors.forename: Serge
authors.initials: S
authors.lastname: Kokot
mesh_terms: D000465:Algorithms; D002138:Calibration; D002626:Chemistry, Pharmaceutical; D016002:Discriminant Analysis; D004340:Drug Contamination; D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D029523:Illicium / Q000737:chemistry*; D016014:Linear Models; D025341:Principal Component Analysis; D019265:Spectroscopy, Near-Infrared; D058067:Wavelet Analysis
chemical_list: D004365:Drugs, Chinese Herbal
keywords: Chemometrics; Illicium verum Hook. F. and Iuicium lanceolatum A.C. Smith; Medicinal and adulterated samples; Near- and mid-infrared spectroscopy