Capillary electrophoretic separation of cationic porphyrins.
Capillary electrophoretic separation of cationic porphyrins.
复制标题
阳离子卟啉的毛细管电泳分离。
DOI：
10.1016/s0021-9673(97)01172-2
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
Wojtowicz,H
中科院分区：
文献类型：
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作者：
Dixon,DW;Pu,G;Wojtowicz,H
阳离子卟啉具有广泛的用途，包括作为核酸结合剂和裂解剂、作为潜在的药理学试剂、作为分子内电子转移过程中的电子供体/受体以及作为分析试剂。在此，我们报道了在 pH 2-5 的磷酸盐缓冲液中，通过熔融石英毛细管电泳分离阳离子卟啉。本工作中研究的卟啉是通过母体四吡啶基卟啉 (TPyP) 的烷基化合成的，得到各种吡啶鎓卟啉。例如，TPyP的甲基化产生单-、顺-二-、反-二-、三-和四甲基化卟啉的混合物[例如，5,10,15,20-四(N-甲基-4-吡啶鎓基)-21H,23H-卟啉，TMPyP(4)]。对合成混合物进行毛细管电泳显示其中四种化合物得到分离。用碘丙酸和溴丙胺烷基化后的混合物也被分离。通过离心分配色谱法小规模制备分离顺式二甲基化和三甲基化 TMPyP 衍生物。毛细管电泳也用于分离金属 TMPyP(4) 配合物，包括钴、铜、铁、锰、钯、锡、钒和锌的配合物。还分离了 5,10,15,20-四(N-甲基-2-吡啶鎓基)-21H,23H-卟啉 TMPyP(2) 的构象异构体（阻转异构体）。净电荷、分子量和分子形状都有助于毛细管电泳条件下阳离子卟啉的差异保留。通过评估 TMPyP(4) 及其丁基和辛基类似物的分离与溶液条件的函数关系，探讨了影响分离的其他因素，包括卟啉的聚集和质子化。阳离子卟啉很难用传统的色谱方法分离；毛细管电泳和离心分配色谱为分离此类化合物提供了极好的新技术。
Cationic porphyrins have a wide variety of uses including those as nucleic acid binding and cleaving agents, as potential pharmacological agents, as electron donor/acceptors in intramolecular electron transfer processes and as analytical reagents. Herein, we report the separation of cationic porphyrins by capillary electrophoresis on fused silica in phosphate buffer at pH 2–5. The porphyrins studied in this work were synthesized from alkylation of the parent tetrapyridylporphyrin (TPyP) to give various pyridinium porphyrins. For example, methylation of TPyP gives a mixture of the mono-, cis-di-, trans-di-, tri- and tetramethylated porphyrins [e.g., 5,10,15,20-tetrakis(N-methyl-4-pyridiniumyl)-21H,23H-porphyrin, TMPyP(4)]. Capillary electrophoresis on a synthetic mixture showed separation of four of these compounds. Mixtures after alkylation with iodopropionic acid and bromopropylamine were also separated. The cis-di- and trimethylated TMPyP derivatives were separated on a small preparative scale by centrifugal partition chromatography. Capillary electrophoresis was also used to separate metallo TMPyP(4) complexes including those of cobalt, copper, iron, manganese, palladium, tin, vanadium and zinc. The conformational isomers (atropisomers) of 5,10,15,20-tetrakis(N-methyl-2-pyridiniumyl)-21H,23H-porphyrin, TMPyP(2), were also separated. Net charge, molecular mass and molecular shape all contribute to the differential retention of cationic porphyrins under capillary electrophoresis conditions. Additional factors affecting the separations, including aggregation and protonation of the porphyrins, were probed by evaluating the separation of TMPyP(4) and its butyl and octyl analogs as a function of solution conditions. Cationic porphyrins are difficult to separate using traditional chromatographic methods; capillary electrophoresis and centrifugal partition chromatography provide excellent new techniques for separation of this class of compounds.