1.0代树形大分子(PAMAM)的合成及对阴阳离子的识别

The Synthesis of G1.0 Poly (amidoamine) Dendrimer (PAMAM) and the Recognition with Anions and Cations

目前生物体内ATP合酶催化ATP水解的研究是生物催化方向的研究热点。为了探索ATP合酶催化ATP水解的机制,本研究模拟生物体系环境,在N2氛围中,采用甲醇溶液回流的发散合成法合成了多功能化的树形大分子,用核磁、红外光谱等方法对其结构进行了表征,并利用其多作用位点的特征对不同阴阳离子进行了识别作用的分析。结果表明:G1.0 PAMAM(L)与Mn2+的识别效果最明显,荧光强度增加18倍,根据修饰的Benesi-Hildebrand方程得到了G1.0 PAMAM与Mn2+最佳配位比为1∶1,结合常数为1.13×104L/mol;采用Job’s法对主客体配位比进行了验证;同时,F-对G1.0 PAMAM荧光猝灭现象最明显,根据修饰的Benesi-Hildebrand方程确定了两者的最佳配位比为1∶1,结合常数为2561 L/mol。该结果开辟了新的一类模拟酶催化剂体系,并为研究ATP合酶的作用机理提供理论依据。

The ATP hydrolysis catalyzed by ATPase becomes the research hotspot in biocatalysis fields. In order to study the mechanism of ATPase catalysis,we mimic the biotic environment in this paper.Multi-functional dendrimer G1.0 PAMAM（L） as a ligand was synthesized by divergent method. The raw material was refluxed in methanol solution under nitrogen.Then the product was characterized by FR-IR,1H NMR and13 C NMR. Make use of its more active sites,it was studied for the recognition between ligand and anions（cations）. The results show that there is the most obvious recognition intention between G1.0PAMAM（L） and Mn2＋.The fluorescent intensity of L is increased by 18-fold. According to the modified Benesi-Hildebrand equation, the optimum molar ratio of L and Mn2＋is calculated as 1∶1.The binding constant is 1.13×104L/mol using Job＇s method.Meanwhile,the recognition between L and anions is also studied.The optimum molar ratio of the subject and object is validated result is that F-can interact with L.The fluorescent quenching is linearly reduced with depending on the increasing concentration of F-.According to the modified Benesi-Hildebrand equation,it can be calculated that the optimum molar ratio is1∶1.The binding constant is 2561 L/mol.The results open up the new kinds of mimic catalyst system.It can be supplied the theoretical foundation for research on mechanism of catalysis of ATPase.