四碘甲状腺素团簇结构与光谱性质的密度泛函理论研究

在B3LYP/Lanl2mb基组水平上,利用密度泛函理论(DFT)优化了四碘甲状腺素团簇的几何结构.基于该团簇的几何结构下,其吸收和发射光谱的研究使用相同的基组水平并采用极化连续介质模型(PCM)下用含时密度泛函理论(TDDFT).研究结果表明,优化所得甲状腺素团簇的几何结构对称性为C_1;在基态稳定结构基础上,得出其输运性质,即甲状腺素团簇为p型输运材料;通过含时密度泛函理论,在优化好的基态结构基础上,又计算了它的溶剂效应,进一步得出该分子在水溶剂中的吸收光谱和发射光谱特性.     

Determination of tetraiodothyronine in serum by HPLC and electrochemical detection

Tetraiodo-L -thyronine (T4) in human serum was determined by HPLC using a nonphysiological internal standard. For sample preparation, a cation exchange resin, RP-chromatography on C-18 or phenylphase, and electrochemical detection (Metrohm 656 or BAS-LC 4 A) were employed. The mobile phase (0.8 ml/min) was 10 mM H₃PO₄/CH₃OH (40/60 v/v) or 10 mM H₃PO₄/CH₃CN (70/30 v/v, 1.5 ml/min), the voltage applied 800 mV. The coefficient of variation (day to day) was 6.8% (N = 40); concentrations of T4 found were 11 to 20% lower than those obtained by two different commercially available immunoassays.