Preparation And Characterization Of Succinate-eighteen-amide Sulfonate Gadolinium Salt And Its Inclusion Compound

Magnetic resonance imaging（MRI）is the most commonly used and effectivenon-invasive imaging diagnostic method in the early stage of tumor.It is often necessary to use contrast agent to improve the diagnostic ability.At present,all the clinical contrast agents are complex of small molecular Gd molecules with molecular weight of 600⁸00.Magnetic resonance contrast agent molecules because of its high efficiency,long residence time in the relaxation,good organ selectivity and side effects of small advantages and gradually attracted much attention.The larger molecular contrast agents containing rare earth elements are becoming more and more hot,especially gadolinium contrast agents.A new macromolecular gadolinium salt:succinate mono eighteen amide sulfonic acid gadolinium（Gd₂（SOAS）₃）and its relative molecular weight is 1657.39,was synthesized in this thesis.Gd₂（SOAS）₃ was synthesized by direct precipitation of sodium succinate mono-eighteen amide sulfonate（SOAS）and gadolinium chloridevia ion exchange.The purity of Gd₂（SOAS）₃ was indirectly measured by the silver method,reaching 98.71%.By elemental analysis,inductively coupled plasma atomic emission spectrometry（ICP）,ash analysis,infrared spectrum characterization,illustrate the structure characteristics of succinate mono eighteen amide sulfonic acid gadolinium,its molecular formula is Gd₂(C₁₈H₃₇NHCOCH₂CHSO₃COO)₃.The solubility test shows that the solubility of Gd₂（SOAS）₃ in water and oil phase was poor.Try to use the Tween series（T-20,T-60,T-80）,Spann series（SP-40,SP-60,SP-80）,polyvinyl alcohol（PVA）,alkylethoxyglucoside（AEG）,alkyl glucoside（APG）,Pimpinga（AEO）and nonylphenol（OP-10）and a series of nonionic surfactant solubilized Gd₂（SOAS）₃.Finally,AEG was selected as a solutizer.Through single factor experiment,it wasfound that when the mass of AEG and Gd₂（SOAS）₃ is 1:1,The transparent dispersion system can be obtained,and the system was relatively stable.Than,try to use beta cyclodextrin and its derivatives of the inclusion of Gd₂（SOAS）₃ and its solution.Meanwhile,the polyglycol（PEG）molecule was combined with theβ-CD.The results made the water solubility ofβ-CD significantly improved by introducing PEG molecule,and the complex system is stable,and also provided a good carrier for the inclusion complex of Gd₂（SOAS）₃.It belongs to the derivative of beta-cyclodextrin.The preparation of the inclusion complex was confirmed by SEM analysis,infrared spectrum,XRD and fluorescence analysis.Although the Gd₂（SOAS）₃ prepared in this paper is insoluble in aqueous phase,Gd₂（SOAS）₃ after AEG solubilization and their inclusion complexes have good water solubility.And Gd₂（SOAS）₃ has unique structural characteristics.It is expected to become a new type of MRI contrast agent.