title: Comparative study of different approaches for multivariate image analysis in HPTLC fingerprinting of natural products such as plant resin.
abstract: Considering the introduction of phytochemical fingerprint analysis, as a method of screening the complex natural products for the presence of most bioactive compounds, use of chemometric classification methods, application of powerful scanning and image capturing and processing devices and algorithms, advancement in development of novel stationary phases as well as various separation modalities, high-performance thin-layer chromatography (HPTLC) fingerprinting is becoming attractive and fruitful field of separation science. Multivariate image analysis is crucial in the light of proper data acquisition. In a current study, different image processing procedures were studied and compared in detail on the example of HPTLC chromatograms of plant resins. In that sense, obtained variables such as gray intensities of pixels along the solvent front, peak area and mean values of peak were used as input data and compared to obtained best classification models. Important steps in image analysis, baseline removal, denoising, target peak alignment and normalization were pointed out. Numerical data set based on mean value of selected bands and intensities of pixels along the solvent front proved to be the most convenient for planar-chromatographic profiling, although required at least the basic knowledge on image processing methodology, and could be proposed for further investigation in HPLTC fingerprinting.
authors.affiliation: Innovation Centre of Faculty of Chemistry Ltd., Studentski trg 12-16, 11000 Belgrade, Serbia.
authors.forename: Petar
authors.initials: P
authors.lastname: Ristivojević
authors.affiliation: University of Belgrade - Faculty of Chemistry, P.O. Box 51, 11158 Belgrade, Serbia. Electronic address: jvelicko@chem.bg.ac.rs.
authors.forename: Jelena
authors.initials: J
authors.lastname: Trifković
authors.affiliation: National Institute of Chemistry, Laboratory for Food Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia.
authors.forename: Irena
authors.initials: I
authors.lastname: Vovk
authors.affiliation: University of Belgrade - Faculty of Chemistry, P.O. Box 51, 11158 Belgrade, Serbia.
authors.forename: Dušanka
authors.initials: D
authors.lastname: Milojković-Opsenica
mesh_terms: D001688:Biological Products / Q000032:analysis*; D002855:Chromatography, Thin Layer / Q000295:instrumentation / Q000379:methods*; D010636:Phenols / Q000032:analysis; D010944:Plants / Q000737:chemistry / Q000145:classification; D025341:Principal Component Analysis; D015203:Reproducibility of Results; D012116:Resins, Plant / Q000032:analysis*; D055771:Serbia; D013045:Species Specificity
chemical_list: D001688:Biological Products; D010636:Phenols; D012116:Resins, Plant
keywords: High-performance thin-layer chromatography; Image analysis; Pattern recognition technique; Phenolics profile; Plant resins