title: Preparation of solid-phase microextraction fibers by in-mold coating strategy for derivatization analysis of 24-epibrassinolide in pollen samples.
abstract: A novel and simple in-mold coating strategy was proposed for the preparation of uniform solid-phase microextraction (SPME) coatings. Such a strategy is based on the direct synthesis of the polymer coating on the surface of a solid fiber using a glass capillary as the mold. The capillary was removed and the polymer with well-controlled thickness could be coated on the silica fiber reproductively. Following the strategy, a new poly(acrylamide-co-ethylene glycol dimethacrylate) (poly(AM-co-EGDMA)) coating was prepared for the preconcentration of 24-epibrassinolide (24-epiBL) from plant matrix. The coating had the enrichment factor of 32 folds, and the extraction efficiency per unit thickness was 5 times higher than that of the commercial polydimethylsiloxane/divinylbenzene (PDMS/DVB) coating. A novel method based on SPME coupled with derivatization and large volume injection-high performance liquid chromatography (LVI-HPLC) was developed for the analysis of 24-epiBL. The linear range was 0.500-20.0 μg/L with the detection limit of 0.13 μg/L. The amounts of endogenous 24-epiBL in rape and sunflower breaking-wall pollens samples were determined with satisfactory recovery (77.8-104%) and reproducibility (3.9-7.9%). The SPME-DE/LVI-HPLC method is rapid, reliable, convenient and applicable for complicated plant samples.
authors.affiliation: School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China.
authors.forename: Jialiang
authors.initials: J
authors.lastname: Pan
authors.forename: Yuling
authors.initials: Y
authors.lastname: Hu
authors.forename: Tingan
authors.initials: T
authors.lastname: Liang
authors.forename: Gongke
authors.initials: G
authors.lastname: Li
mesh_terms: D001709:Biotechnology / Q000295:instrumentation / Q000379:methods; D029741:Brassica rapa / Q000737:chemistry; D060406:Brassinosteroids / Q000032:analysis* / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D006368:Helianthus / Q000737:chemistry; D057230:Limit of Detection; D011058:Pollen / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D015203:Reproducibility of Results; D052617:Solid Phase Microextraction / Q000295:instrumentation* / Q000379:methods; D013260:Steroids, Heterocyclic / Q000032:analysis* / Q000302:isolation & purification
chemical_list: D060406:Brassinosteroids; D011109:Polymethacrylic Acids; D013260:Steroids, Heterocyclic; D011092:Polyethylene Glycols; C023623:brassinolide