released into the cells to decrease the melanin synthesis too. Based on the acts of microneedles on the skin, an active targeting drug delivery system which has double targeted effects and double function of anti-pigmentation was constructed. The ration and the distribution of NPs in the hareless mouse skin and the human skin treated with microneedles were studied using NPs containing coumarin 6 and R-phycoerythrin (R-PE) as fluorescent probe. Confocal laser scanning microscopy (CLSM) was used to visualize the distribution of nanoparticles and the high performance liquid chromatography (HPLC) was utilized to quantified the amount of the nanoparticles. The CLSM images revealed that NPs could rate into the skin through the microconduits created with microneedles. Permeation study in vitro demonstrated that (i) the permeation of NPs into the skin was enhanced by microneedles; (ii) much more NPs deposited in the epidermis than those in the dermis, but no NP reached the receptor solution;(iii) the permeation was in a particle size-dependent manner. It was also found that the enhancement degree by microneedles in the human skin was more significant than that in the hareless mouse skin. B-16 melanoma cells were treated with skin-lightener. The tyrosinase activity, the melanin content and cell viability were respectively measured to optimize the drug. The results showed that the arbutin was the best drug with high anti-melanogenesis effect and low toxicity. The arbutin-loaed NPs preparation was optimized by the orthogonal design. The pharmaceutical characteristics of NPs made with the optimized prescription were evaluated. The results showed that the NPs were quite round and homogenous with the average size of about 200nm. ASIP was conjugated to the NPs by EDC and NHS to prepare the active targeting NPs. The resultant arbutin-NPs-ASIP was stable. The ASIP labeled with fluorescent R-phycoerythrin (R-PE) was used to modifiy the NPs. The fluorescent NPs were detected by the
