Shanghai Skin Disease Hospital, Shanghai, People's Republic of China.
Int J Nanomedicine. 2013;8:2669-76. doi: 10.2147/IJN.S45821. Epub 2013 Jul 24.
5-Aminolevulinic acid (ALA) is a prodrug for topical photodynamic therapy. The effectiveness of topical ALA can be limited by its bioavailability. The aim of this study was to develop a novel ALA delivery approach using poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs).
A modified double emulsion solvent evaporation method was used to prepare ALA loaded PLGA NPs (ALA PLGA NPs). The characteristics, uptake, protoporphyrin IX fluorescence kinetics, and cytotoxicity of ALA PLGA NPs toward a human skin squamous cell carcinoma cell line were examined.
The mean particle size of spherical ALA PLGA NPs was 65.6 nm±26 nm with a polydispersity index of 0.62. The encapsulation efficiency was 65.8%±7.2% and ALA loading capacity was 0.62%±0.27%. When ALA was dispersed in PLGA NPs, it turned into an amorphous phase. ALA PLGA NPs could be taken up by squamous cell carcinoma cells and localized in the cytoplasm. The protoporphyrin IX fluorescence kinetics and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay showed that ALA PLGA NPs were more effective than free ALA of the same concentration.
PLGA NPs provide a promising ALA delivery strategy for topical ALA-photodynamic therapy of skin squamous cell carcinoma.
5-氨基酮戊酸（ALA）是局部光动力疗法的前体药物。其生物利用度可能会限制局部 ALA 的疗效。本研究旨在采用聚（乳酸-共-乙醇酸）（PLGA）纳米粒（NPs）开发一种新的 ALA 递药方法。
采用改良的双乳液溶剂蒸发法制备 ALA 负载的 PLGA NPs（ALA-PLGA NPs）。检测了 ALA-PLGA NPs 的特性、摄取、原卟啉 IX 荧光动力学和对人皮肤鳞状细胞癌细胞系的细胞毒性。
球形 ALA-PLGA NPs 的平均粒径为 65.6nm±26nm，多分散指数为 0.62。包封效率为 65.8%±7.2%，ALA 载药量为 0.62%±0.27%。当 ALA 分散在 PLGA NPs 中时，它转变成无定形相。ALA-PLGA NPs 可被鳞状细胞癌细胞摄取并定位于细胞质中。原卟啉 IX 荧光动力学和 3-[4,5-二甲基噻唑-2-基]-2,5-二苯基四氮唑溴盐试验表明，ALA-PLGA NPs 比相同浓度的游离 ALA 更有效。
PLGA NPs 为皮肤鳞状细胞癌的局部 ALA-光动力疗法提供了一种有前途的 ALA 递药策略。
