The Preparation And Characterization Of Novel Solid-phase Microextraction Fiber

As a new and remarkable sample preparation technique, solid-phase microextraction (SPME) has been widely applied in different fields including the environment, food, natural products, pharmaceuticals, biology, toxicology, and forensics due to its high efficiency, non-solvent demanding, and facilitation in automation and coupling techniques. As the core of the SPME device, the coating material determines the sensitivity and selectivity of the technique. The available commercial SPME coatings play the most important role in the development of SPME technology, but some drawbacks such as nonresistance to high temperature and organic solvents, low selectivity, poor reproducibility, high cost and short life time, restrict its further application. Therefore, the exploration of SPME fiber coating material in both high selectivity and sensitivity raises huge concern in the chemical and other chemistry-related community with its immense potential in application across fields.In this study, Vinyl-SBA-15 mesoporous silica was prepared and used as coating material of SPME with two coating techniques including sol-gel coating method, direct coating method by exoxy resin glue for the first time. An approach by using mold was used in this work to overcome the drawbacks of the traditional sol-gel coating process. Results showed that Vinyl-SBA-15 fiber prepared by two methods exhibited high thermal stability, excellent solvent durability in methanol and acetonitrile. Compared to commercial fiber, Vinyl-SBA-15 fibers prepared by two coating techniques represented a significantly improved extraction efficiencies for both polar (phenols) and BTEXs (benzene, toluene, ethylbenzene and o-xylene) compounds. Good repeatability of one fiber (n=6) and reproducibility for three prepared fibers of two coating methods were obtained. The fibers were successfully applied to the determination of BTEX and phenols in three spiked water samples.Morever, in order to fill up the blank of homemade SPME fiber of analyzing organotin, PDMS/Chitosan composite fiber was synthesized by sol-gel method combining with corrosion the mold by hydrofluoric acid. Results showed that PDMS/Chitosan composite fiber exhibited a better extraction efficiencies for butyltin compounds compared with commercial fiber, especially after corrosion of hydrofluoric acid. HS-SPME conditions such as extraction time, desorption time, temperature, salt effect, pH and concertraction of derivatizing reagent were optimized. The fibers were successfully applied to the determination of butyltin compounds of the dock water samples of Sun Yat-sen university and Wanzi in ZhuHai.