血红蛋白催化导电聚苯胺合成的模板功能

Role of Template in Hemoglobin Biocatalytic Synthesis of Conducting Polyaniline

利用UV vis分光光度法对不同类型聚电解质、胶束、非胶束和混合胶束等模板导向血红蛋白(Hb)生物催化方法制备水溶性导电聚苯胺进行了研究.发现模板不同于水溶液,它不仅能提供必需的低pH值和一定量电荷密度的局部环境,还能定位、组织、并与苯胺反应,最终控制聚苯胺的类型.强酸型聚电解质(如聚苯乙烯磺酸)模板和强酸型表面活性剂分子(如十二烷基磺酸或十二烷基苯磺酸)形成的胶束模板是最理想的模板.它们能提供必需的低pH值和一定量电荷密度的局部环境促进导电聚苯胺形式的形成.当反应媒介中不能形成胶束或胶束体系中带电荷的磺酸基团之间的距离过大,则导电形式的聚苯胺不能形成.结果表明:模板在Hb催化合成导电聚苯胺过程中起重要作用.

Using a template-guided Hemoglobin (Hb) biocatalytic approach for the synthesis of a water soluble and conducting polyaniline is presented. The different types of polyelectrolytes, micellar, non-micellar and mixed micellar templates were investigated by UV-vis spectrophotometer. It was found that the template not only provides a necessary type of local environment where the pH and charge density near the template molecule is different from that of the bulk solution, but anchors, aligns, and reacts the aniline monomers and ultimately controls what form of polyaniline. Strong acid polyelectrolytes, such as sulfonated polystyrene and micelles formed from aggregating, strong acid surfactant molecules such as sodium dodecylsulfonic acid and sodium dodecylbenzenesulfonic acid are the most favorable because they provide a necessary type of local environment where the pH and charge density near the template molecule that lead to the formation of conducting polyaniline. However, if the reaction media was such that micelles were not formed or if the distance between the sulfonated headgroups in the mixed micelle systems was too large, then the conducting form of polyaniline could not be obtained. This result showed that template played an important role in the course of Hb catalytic synthesis of a conducting polyaniline.