Distribution of Xanthene Dyes in DPPC Vesicles: Rationally Accounting for Drug Partitioning Using a Membrane Model

Journal of the Brazilian Chemical Society

Universidade de São Paulo, Ribeirão Preto, Brazil¹  Caetano, Wilker¹  Universidade Estadual de Maringá, Maringá, Brazil¹  Calori, Italo R.¹  Hioka, Noboru¹  Pereira, Paulo C. S.¹  Cesar, Gabriel B.¹  Universidade de São Paulo, São Paulo, Brazil¹  Vanzin, Douglas¹  Pellosi, Diogo S.¹  Politi, Mario J.¹ 

关键词:  xanthene dye;    DPPC liposome;    membrane interface;    photodynamic activity;   

DOI  :  10.5935/0103-5053.20160079

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

The correct selection of a dye that has effective action as a photosensitizer is a primary concern for successful therapeutic outcomes. The effectiveness of the photodynamic agent is related to both the targeting of cell membranes and the photochemical yield of the chosen dye. The distributions of xanthene derivatives Eosin Y, Erythrosin B, and Rose Bengal B in vesicles of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) in both liquid-crystalline and gel phases were investigated by fluorescence spectroscopy. Binding constants, fluorescence anisotropy, fluorescence quenching, fluorescence quantum yield, and fluorescence resonance energy transfer at physiological pH conditions were determined. To Erythrosin B and Eosin Y, the iodide quenching rate constant was shown to involve a sphere of action mechanism driven by a specific interaction between Erythrosin B and Eosin Y molecules and the choline head-group of the phospholipid; in contrast, Rose Bengal B was located deep in the membrane and this mechanism was not present. The dyes can be ordered by their penetration depth in the membrane, and this order was found to be Eosin Y < Erythrosin B < Rose Bengal B. These results demonstrate a rational approach for the screening of more active agents for photodynamic therapy based on the affinity between the xanthene derivatives and DPPC vesicles.

【 授权许可】

Unknown