Application Of Molecularly Imprinted Solid Phase Extraction And Fluorescence Quenching In Pharmaceutical Analysis

Molecular imprinting polymer (MIP) based on the molecular recognition theory, which becomes a potential stationary phase in the solid-phase extraction. The combination of MIP and solid-phase extraction (MISPE) has been used in determining trace analytes in drug, biological and environmental samples. The application of MIP in SPE has become the most promising development of selective SPE method for trace analysis. In this paper, new solid-phase sorbents were synthesized and extraction performances were studied in detail.1.Metronidazole (MNZ) chosen as the research target, metronidazole ester (MNZ-Es) for template molecule, through computational investigation between functional monomer and template molecular interactions , determine the optimal monomer for methyl acrylic acid (MAA). Adopt Ethylene Glycol Dimethacrylate for crosslinking agent, Azodiisobutyronitrile (AIBN) for initiator, chloroform as a porogen solvent, using bulk polymerization synthesis dummy template molecularly imprinted polymer DMIPs.2. Through batch binding experiment, characterize the selectivity and imprinting factor (IF) of MIPs. The applicability of the MISPE-HPLC-UV method was tested for extraction of bovine serum spiked with metronidazole on MISPE and NISPE with recoveries of 97% and 64%, respectively. The high selective pseudo-template imprinting demonstrated the ability of overcome template bleeding.3. The charge-transfer reaction of 2, 3-dichloro-5, 6-dicyano-1, 4-benzoquinone(DDBQ)as an electron acceptor with Lidocaine as electron donor was investigated by spectrophotometer. In acetonitrile, DDBQ was found to react with Lidocaine and produce a stable charge-transfer complex. Therefore a high-selectivity charge-transfer reaction method for the determination of LD has been developed. The method has been applied to the determination of Lidocaine injection with satisfactory results.4. Using fluorescence and ultraviolet absorption spectrometry, bovine serum albumin (BSA) and Metronidazole, Metronidazole ester and Zidovudine ester interactions were studied. In normal physiological condition, each drug has strong fluorescence quenching on BSA, According to the quenching at different drug concentrations, and different temperatures change ultraviolet absorption spectra, and it can be concluded that the quenching is multi-fluorescence quenching. According to the reaction thermodynamic parameters, the interaction between MNZ and MNZ-Es and the BSA mainly is electrostatic interaction, the interaction between AZT-Es and BSA is hydrophobic interaction.5. To establish a method for the determination of Metronidazole (MNZ) and 4-nitrophenol (4-NP) by fluorescence quenching.1- pyrenebutyric acid(PBA)was chosen as the best fluorescent reagents, MNZ concentration in 5～40mg/L and 4-NP concentration in 0.6～15mg/L was linearly proportional to quenching amount (F0/F),r=0.9995 and 0.9996,respectively.the proposed method is simple,rapid,sensitive,selective and applicable for the determination of MNZ and 4-NP in environmental samples and biological samples.