Development of β-cyclodextrin-Modified Silica and Polyporous Polymer Particles for Solid-Phase Extraction of Methyl Jasmonate in Aqueous and Plant Samples

Two novel kinds of materials, -cyclodextrin(CD)-modified silica and polyporous polymer particles, were prepared for solid phase extraction of methyl jasmonate (MeJA) in aqueous conditions. -Cyclodextrin-modified silica was prepared by a sol-gel process and polyporous polymer was formed by 4-vinylpyridineas (4-VP) and ethyleneglycol dimethacrylate (EGDMA). For better extraction properties, preparation conditions were optimized. Bare silica particles were prepared for comparison of -cyclodextrin-modified silica, and different kinds of monomers and the ratio of monomer to cross-linker were studied for polyporous polymer. To evaluate the usability of the two materials, extraction kinetics and isotherm curves were systematically studied. The extraction conditions were also optimized and both materials showed good extraction efficiency for MeJA, when evaluating by standard solution, enrichment factors of 56.5 and 75.3 were obtained for MeJA. Solid-phase extraction (SPE) -HPLC methods based on -CD-modified silica and poly(4-VP-EGDMA) were also established for the determination of MeJA in aqueous samples. Good linearity was observed with R20.998, and the low detection limits were found to be 2 and 3ng/mL by UV detection. Finally, -CD-modified silica and poly(4-VP-EGDMA) based SPE-HPLC methods have successfully been applied to determine MeJA in the wintersweet flower; recoveries were tested and found to be in the range of 79.0 to 87.3%.