TPPS4的电化学分析法，TPPS4和BSA的相互作用以及环糊精对二者作用体系影响的荧光法研究

目的确立一种快速、准确检测水溶性卟啉(TPPS₄)的分析方法,从而进一步了解水溶性卟啉和牛血清白蛋白(BSA)之间相互作用的机制。方法采用电化学法对TPPS₄的极谱伏安行为进行了研究,同时采用电化学法、荧光法和紫外法对TPPS₄与BSA之间的相互作用分别进行了研究。3种方法相互辅证使得试验结果更加可靠。结果在底液NaH₂PO₄-Na₂HPO₄缓冲液(pH 7.18)中,TPPS₄在-0.70 V(vs SCE)处有一个稳定而灵敏的还原峰,其峰电流与TPPS₄浓度在1.0×10^-7～1.0×10^-5 mol·L^-1有良好的线形关系(r²=0.998 3,0.999 3),检测限LOD为3.0×10^-8 mol·L^-1。平均标准回收率为99.59%,精密度较好,RSD为0.56%(n=5)。在NH₄Cl-NH₃·H₂O缓冲液(pH 9.05)中,实验结果表明BSA与TPPS₄相互作用生成1∶1的TPPS₄-BSA超分子体系。另外,加入环糊精体系后,磺丁醚-β-CD(SBE-β-CD)和羟丙基-β-CD(HP-β-CD)均能促进TPPS₄与BSA发生反应。结论建立了一种简单、快速、准确的水溶性卟啉四-(4-磺基苯)卟啉(TPPS₄)的电化学分析方法。卟啉类药物被环糊精包合后更容易与人体内的蛋白质进行作用,环糊精在卟啉类药物的控制、释放中具有重要的作用和意义。

Electroanalytical method for TPPS4, the interaction of TPPS4 with BSA and the influence of CDs on it by fluorescence spectroscopy

AIM: To establish a simple, rapid and accurate electroanalytical method for water soluble porphyrin meso-tetrakis-(4-sulfonatophenyl) porphyrin (TPPS4); to clarify the reaction between water soluble porphyrins and bovine serum albumin (BSA); and to determine the interaction of TPPS4 with BSA in the absence of presence of cyclodextrins (CDs), separately. METHODS: Three methods including LSV, UV spectroscopy and fluorescence spectroscopy had been employed to the relevant experiments. The way of employing three methods at the same time could make the experiment results more reliable. RESULTS: In the supporting electrolyte of NaH2 PO4-Na2 HPO4 (pH 7.18), a sensitive reduction peak of TPPS4 was found by linear sweep voltammetry (LSV), the peak potential (Ep) was -0.70 V (vs SCE). The relationship between the second derivative peak of LSV (ip") and the concentration of TPPS4 was linear from 1.0 x 10(-7) mol x L(-1) to 1.0 x 10(-5) mol x L(-1), the square of correlation coefficients (r2) were 0.998 3 and 0.999 3, respectively. The relative standard deviation (RSD) was 0.56% (n = 5). The mean recovery of TPPS4 was 99.59%. In NH4Cl-NH3 x H2O buffers (pH 9.05), it was proved that BSA and TPPS4 could interact with each other and form 1 : 1 TPPS4-BSA supramolecular system. Moreover, the interaction between TPPS4 and BSA had been investigated by adding cyclodextrins (CDs). The interaction of TPPS4 with BSA was facilitated both by hydroxypropyl-beta-CD (HP-beta-CD) and sulforbutylether-beta-CD (SBE-beta-CD). CONCLUSION: An electroanalytical method for TPPS4 has been established by LSV. The porphyrin drugs included by CDs could react with protein existing inside the human body easier. The consequences of this article also show that CDs will play important role in controlling and releasing the porphyrin drugs.