Program of Petrochemistry and Polymer Science, Chulalongkorn University, Bangkok 10330, Thailand.
Int J Pharm. 2011 Feb 14;404(1-2):281-8. doi: 10.1016/j.ijpharm.2010.11.019. Epub 2010 Nov 18.
Retinyl acetate (RA) loaded polymeric nanoparticle (NP) carriers were prepared using two different single polymers, ethyl cellulose (EC) and poly (ethylene glycol)-4-methoxycinnamoylphthaloylchitosan (PCPLC). The stability of RA to aqueous solution and UVA light was significantly improved when encapsulated with PCPLC, whilst EC encapsulation gave some improved stability in water but showed no improved photostability. Ex vivo application of free RA and the RA-loaded PCPLC NPs onto the surface of the freshly excised skin from a baby mouse indicated a significantly slower skin absorption rate for the encapsulated RA. However, 100% retention of the encapsulated RA in the skin tissue was observed after 24h. Confocal fluorescent analysis of the skin pieces applied with the RA-loaded PCPLC NPs indicated likely entry and accumulation of the PCPLC NPs and RA at the hair follicles. Release of RA from the PCPLC NP carriers was confirmed through the detection of an increasingly higher RA/PCPLC fluorescent signal ratio deeper into the dermis and away from the hair follicles.
醋酸视黄酯（RA）负载的聚合物纳米颗粒（NP）载体采用两种不同的单一聚合物，乙基纤维素（EC）和聚（乙二醇）-4-甲氧基肉桂酰基邻苯二甲酰壳聚糖（PCPLC）制备。当用 PCPLC 包封时，RA 对水溶液和 UVA 光的稳定性得到了显著提高，而 EC 包封在水中提供了一些改善的稳定性，但没有改善光稳定性。将游离 RA 和负载 RA 的 PCPLC NPs 应用于从新生小鼠体表面新鲜取出的皮肤表面，表明包封的 RA 的皮肤吸收速度明显较慢。然而，在 24 小时后观察到 100%的包封 RA 保留在皮肤组织中。用负载 RA 的 PCPLC NPs 处理的皮肤片段的共聚焦荧光分析表明，PCPLC NPs 和 RA 可能进入和积聚在毛囊中。通过检测更深到真皮并远离毛囊处的 RA/PCPLC 荧光信号比值的不断增加，证实了 RA 从 PCPLC NP 载体中的释放。
