5-Aminolevulinic acid loaded ethosomal vesicles with high entrapment efficiency for in vitro topical transdermal delivery and photodynamic therapy of hypertrophic scars

• DOI: 10.1039/c6nr06872c
• Publication Date: 2016-10-26T07:54:14Z
• Authors: Zheng Zhang; Yunsheng Chen; Heng Xu; Yan Wo; Zhen Zhang; Ying Liu; Weijie Su; Daxiang Cui; Yixin Zhang
• Keywords: Transcellular; Hypertrophic scars; Calcein; Protoporphyrin IX

Photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is an alternative for hypertrophic scars (HS), which destroys human scar fibroblasts (HSF). However, the poor permeability of ALA both in HS tissue and HSF significantly restricts PDT HS. To overcome these barriers, ALA-loaded ethosomal vesicles (ALA-ES) were developed by a pH gradient active loading method characterized morphology, entrapment efficiency (EE) stability. Results show that prepared ALA-ES are homogenous spherical lamellar vesicles, 53 ± 7 nm size, 50.6 2.3% EE have excellent In vitro transdermal delivery studies through carried out using Franz diffusion cells. Compared to traditional hydroalcoholic solution (ALA-HA), achieve higher drug retention less administration time, fluorescence microscopy showed penetrate into deeper dermis shorter indicating can enhance penetration Additionally, was visualized first time transmission electron (TEM). The irregular collapsed suggest they squeeze narrow spaces target area release Taking as target, transcellular cells investigated intracellular protoporphyrin IX (PpIX) accumulation. cells, including formation reactive oxygen species (ROS) cell apoptosis, also well investigated. Furthermore, detailed changes observed TEM. results strongly indicate facilitate cause level apoptosis or necrosis than ALA-HA. high therefore promising system topical has great potential ALA-PDT