title: Hydrophobic-hydrophilic monolithic dual-phase layer for two-dimensional thin-layer chromatography coupled with surface-enhanced Raman spectroscopy detection.
abstract: Hydrophobic-hydrophilic monolithic dual-phase plates have been prepared by a two-step polymerization method for two-dimensional thin-layer chromatography of low-molecular-weight compounds, namely, several dyes. The thin 200 μm poly(glycidyl methacrylate-co-ethylene dimethacrylate) layers attached to microscope glass plates were prepared using a UV-initiated polymerization method within a simple glass mold. After cutting and cleaning the specific area of the layer, the reassembled mold was filled with a polymerization mixture of butyl methacrylate and ethylene dimethacrylate and subsequently irradiated with UV light. During the second polymerization process, the former layer was protected from the UV light with a UV mask. After extracting the porogens and hydrolyzing the poly(glycidyl methacrylate-co-ethylene dimethacrylate) area, these two-dimensional layers were used to separate a mixture of dyes with great difference in their polarity using reversed-phase chromatography mode within the hydrophobic layer and then hydrophilic interaction chromatography mode along the hydrophilic area. In the latter dimension only the specific spot was developed further. Detection of the separated dyes could be achieved with surface-enhanced Raman spectroscopy.
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Yangpu District, Shanghai, China.|Department of microbial and biochemical pharmacy, School of life science and technology, China Pharmaceutical University, Nanjing, Jiangshu Province, China.
authors.forename: Binxing
authors.initials: B
authors.lastname: Zheng
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Yangpu District, Shanghai, China.|Department of microbial and biochemical pharmacy, School of life science and technology, China Pharmaceutical University, Nanjing, Jiangshu Province, China.
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Yangpu District, Shanghai, China.|Department of Pharmaceutical Analysis, School of Pharmacy, Fujian University of Traditional Chinese Medicine, Yangpu District, Shanghai, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Yangpu District, Shanghai, China.
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Chai
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Yangpu District, Shanghai, China.|Department of Pharmaceutical Analysis, School of Pharmacy, Fujian University of Traditional Chinese Medicine, Yangpu District, Shanghai, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Lu
authors.affiliation: Department of microbial and biochemical pharmacy, School of life science and technology, China Pharmaceutical University, Nanjing, Jiangshu Province, China.
authors.forename: Jiyang
authors.initials: J
authors.lastname: Xu
mesh_terms: D002855:Chromatography, Thin Layer / Q000379:methods*; D057927:Hydrophobic and Hydrophilic Interactions; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013499:Surface Properties
keywords: Dual-phase layers; Hydrophobic-hydrophilic; Monoliths; Surface-enhanced Raman spectroscopy