Objective To compare transdermal penetration of triamcinolone acetonide liposparticles (TAA-LPPs) and TAA-Ethosomes in vitro. Methods The TAA-LPPs and TAA-Ethosomes were produced and the morphology was observed by transmission electron microscope,particle size was detected by laser particle analyzer. The percutaneous permeability in vitro was tested by modified Franz diffusion pools. The amount of penetrated triamcinolone acetonide and the retention in the skin were de-termined by HPLC. Results The shape of TAA-LPPs and TAA-Ethosomes was almost spherical with mean diameter of (99. 9±1. 3) and (105±1. 4) nm, respectively. The cumulative transdermal penetration of TAA-LPPs, TAA-Ethosomess and TAA suspension was (53. 59±4. 40),(87. 03±4. 87),and (30. 54±8. 61) μg·(cm2 ) -1 , respectively . The drug retention in the skin after 32 h was (1. 02±0. 13), (0. 62±0. 08), (0. 55±0. 17) μg·(cm2 ) -1 , respectively. Conclusion TAA-LPPs is better for transdermal administration of triamcinolone acetonide by reducing systemic absorption of the drug.

Borneol is a traditional Chinese medicine that can promote drug absorption from the gastrointestinal tract and distribution to the brain. However, stomach irritation may occur when high doses of borneol are used. In the present work, gastrodin, the main bioactive ingredient of the traditional Chinese drug "Tianma" (Rhizoma Gastrodiae) was used as a model drug to explore reasonable application of borneol. Sustained-release solid dispersions (SRSDs) for co-loading gastrodin and borneol were prepared using ethylcellulose as a sustained release matrix and hydroxy-propyl methylcellulose as a retarder. The dispersion state of drug within the SRSDs was analyzed by using scanning electron microscopy, differential scanning calorimetry, and powder X-ray diffractometry. The results indicated that both gastrodin and borneol were molecularly dispersed in an amorphous form. Assay of in vitro drug release demonstrated that the dissolution profiles of gastrodin and borneol from the SRSDs both fitted the Higuchi model. Subsequently, gastric mucosa irritation and the brain targeting of the SRSDs were evaluated. Compared with the free mixture of gastrodin and borneol, brain targeting of SRSDs was slightly weaker (brain targeting index: 1.83 vs. 2.09), but stomach irritation obviously reduced. Sustained-release technology can be used to reduce stomach irritation caused by borneol while preserving sufficient transport capacity for oral brain-targeting drug delivery.