Preparation Of Novel Polymer Microspheres And Their Applications In High-performance Liquid/Ion Chromatography

Chromatographic stationary phase is the primary factor that determines the separation properties, therefore development and application of novel stationary phase packings are of important academic and practical significance. In this paper, poly （glycidylmethacrylate-divinylbenzene） （poly （GMA-DVB）） microspheres were prepared by seeded swelling polymerization method and used as substrates for the preparation of high-performance liquid, cation exchange and anion exchange chromatographic stationary phases. The chromatographic properties were investigated. Meanwhile, an ion chromatography column-switching system was establised for the detection of y-hydroxybutyrate in urine sample.In chapter one, the liquid chromatographic stationary phase was reviewed, which mainly included the support materials and the species of functional groups. The organic polymer microspheres used in stationary phases were principally discussed. Furthermore, the development and application of chromatographic column-switching technique were also reviewed.In chapter two, porous poly （GMA-DVB） microspheres were prepared by seeded swelling polymerization method. Scanning electron microscope, nitrogen adsorption-desorption test, fourier transform infrared spectrum and titration experiment were employed to characterize the microspheres. The results showed that the microspheres had good mono-dispersity, large specific surface area and high mechanic strength, which were promising to be used as stationary phase substrates.In chapter three, octadecylamine-modified poly （GMA-DVB） microsphere high-performance liquid chromatographic stationary phase was prepared. Mono-substituted benzenes and nitrosamines were employed to characterize the chromatographic properties of the stationary phase. The results showed that the stationary phase had strong hydrophobicity, stereo-selectivity and π-π interaction, which was especially suitable for the separation of N-nitrosamines.In chapter four, succinic anhydride, phthalic anhydride and maleic anhydride-modified poly （GMA-DVB） cation exchangers were obtained by the direct reaction, respectively. Seven common cations and organic amines were employed to characterize the chromatographic properties of the cation exchangers. The results showed that the retention and separation of succinic anhydride, phthalic anhydride and maleic anhydride-modified poly （GMA-DVB） cation exchangers increased successively. The maleic anhydride-modified cation exchanger exhibited similar separation performance with SCS1 column, which could realize the baseline separation of seven common cations and organic amines.In chapter five, anion exchangers based on poly （GMA-DVB） microspheres of different exchange capacity were prepared by repeated and alternant reaction with amines （methylamine, dimethylamine, trimethylamine, diethylamine and triethylamine） and 1,4-butanediol diglycidyl ether. Seven common anions, organic weak acids and carbohydrates were employed to characterize the chromatographic properties of the anion exchangers. The results showed that high capacity anion exchanger based on poly （GMA-DVB） microspheres could be prepared by two or three times quarternization reaction, which enriched the columns suitable for the separation of organic weak acids and carbohydrates.In chapter six, an ion chromatography column-switching system was established for the detection of γ-hydroxybutyrate in urine sample for the first time. Ion-exclusion chromatography was able to separate γ-hydroxybutyrate from other anions in urine sample, while its determination limit was too high; therefore, the ion-exclusion elution fraction of γ-hydroxybutyrate was transferred to the ion-exchange system for further determination by column-switching technology, and the determination limit of γ-hydroxybutyrate was decreased to 0.08 mg L^-1 which met the needs of direct determination of 0-10 mgL^-1 endogenous γ-hydroxybutyrate in urine.