牛磺胆酸钠对胆红素与钙离子相互作用形成沉淀过程的影响的研究

本工作选择牛磺胆酸钠作为人体内胆汁酸盐的代表研究其对胆色素结石的重要成分——胆红素钙沉淀过程的影响。结果表明,牛磺胆酸钠的存在使胆红素钙沉淀的条件溶度积大大提高,并使沉淀反应速度大大减慢。在牛磺胆酸钠浓度较高的情况下,沉淀过程出现诱导期,说明牛磺胆酸钠在一定条件下可以抑制胆红素钙沉淀的形成。沉淀的红外光谱表明,牛磺胆酸并未结合在沉淀中,也未影响沉淀中胆红素与钙离子间的相互作用的部位。沉淀的扫描电镜观察结果经统计学处理表明牛磺胆酸钠的存在使沉淀的颗粒变小,颗粒的聚集程度减小。

STUDIES ON EFFECTS OF SODIUM TAUROCHOLATE UPON PRECIPITATION OF BILIRUBIN WITH CALCIUM ION

The reaction of bilirubin with calcium ion forming calcium bilirubinate -the important component of pigment gallstone was studied in the absence and presence of various concentrations of sodium taurocholate (TC). In the kinetic studies, the calcium and bilirubin of the reaction mixture in constant pH were monitored as the function of time. The particle size distributions of the precipitates were measured in parallel. The results showed that in the presence of TC, the reaction may be significantly delayed and an induction period is present in a relative concentrated TC background. In thermodynamic aspect, the conditional solubility products were determined and found increase with the increasing TC concentration. The results also showed that the average sizes of particles decrease in the presence of TC. Thus the effects of TC on calcium bilirubi-nate formation include, less precipitates formed, slower reaction rate and smaller particles.