三价铁四-(4-磺酸钠苯基)卟啉与共聚物的相互作用及在复合胶束中的聚集。

Interaction of FeIII-tetra-(4-sulfonatophenyl)-porphyrin with copolymers and aggregation in complex micelles.

机构信息

State Key Laboratory of Hollow Fiber Membrane Materials and Processes, School of Materials Science and Engineering, Tianjin Polytechnic University, Tianjin 300387, People's Republic of China.

出版信息

Langmuir. 2013 Jul 16;29(28):8936-43. doi: 10.1021/la401805x. Epub 2013 Jul 1.

DOI:10.1021/la401805x

PMID:23768050

Abstract

Aggregation of Fe(III)-tetra-(4-sulfonatophenyl)-porphyrin (Fe(III)TPPS) was studied in the presence of block copolymers, poly(ethylene glycol)-block-poly(4-vinylpyridine) (PEG-b-P4VP), poly(ethylene glycol)-block-poly(2-(dimethylamino)ethyl methylacrylate) (PEG-b-PDMAEMA), and poly(ethylene glycol)-block-poly(β-cyclodextrin) (PEG-b-PCD). The interaction between the iron porphyrin and the blocks, P4VP, PDMAEMA, and PCD, led to the formation of copolymers/Fe(III)TPPS complex micelles with a PEG shell and determined the species of Fe(III)TPPS. The electrostatic interaction of protonated P4VP and PDMAEMA with Fe(III)TPPS remarkably decreased the apparent pKd of Fe(III)TPPS and led to a micellar μ-oxo dimer of the iron porphyrin. At pH above the pKa of P4VP, Fe(III)TPPS was kept inside the hydrophobic P4VP core and formed an encapsulated μ-oxo dimer. However, when above the pKa of PDMAEMA, Fe(III)TPPS escaped from the hydrophobic PDMAEMA core, existing as a free μ-oxo dimer. PCD caused the monomer of the porphyrin because of the inclusion complexation between the β-cyclodextrin residues and Fe(III)TPPS. The two micellar monomer species Fe(III)TPPS(H2O)2 and Fe(III)TPPS(OH) were obtained with an equilibrium pKa ~ 6.4.

摘要

在嵌段共聚物存在的情况下研究了 Fe(III)-四-(4-磺酸钠基苯基)卟啉（Fe(III)TPPS）的聚集，嵌段共聚物为聚乙二醇-聚(4-乙烯基吡啶)（PEG-b-P4VP）、聚乙二醇-聚(2-(二甲氨基)乙基甲基丙烯酸酯)（PEG-b-PDMAEMA）和聚乙二醇-聚(β-环糊精)（PEG-b-PCD）。铁卟啉与嵌段 P4VP、PDMAEMA 和 PCD 之间的相互作用导致形成具有 PEG 壳的共聚物/Fe(III)TPPS 复合胶束，并确定了 Fe(III)TPPS 的物种。质子化的 P4VP 和 PDMAEMA 与 Fe(III)TPPS 的静电相互作用显著降低了 Fe(III)TPPS 的表观 pKd，并导致铁卟啉的胶束 μ-氧合二聚体。在 pH 高于 P4VP 的 pKa 时，Fe(III)TPPS 被保留在疏水性 P4VP 核内并形成包封的 μ-氧合二聚体。然而，当 pH 高于 PDMAEMA 的 pKa 时，Fe(III)TPPS 从疏水性 PDMAEMA 核中逸出，以游离的 μ-氧合二聚体形式存在。PCD 引起卟啉单体，因为β-环糊精残基与 Fe(III)TPPS 之间存在包合络合。两种胶束单体物种 Fe(III)TPPS(H2O)2 和 Fe(III)TPPS(OH)通过平衡 pKa~6.4 获得。