米诺地尔-生物可溶性微针的制备及评价

目的 制备治疗脱发的米诺地尔-甲基丙烯酸酰化明胶(GelMA)生物可溶性微针,并对其进行表征和评价。方法 以生物可溶性水凝胶GelMA为基质,采用模印法和紫外交联法制备米诺地尔-GelMA生物可溶性微针,分别采用光学和荧光显微镜表征其形貌,采用机械性能和溶胀率测定考察交联度对微针机械强度和吸水性的影响,采用体外药物释放实验考察其体外药物释放速度;采用动物透皮实验评价其透皮效果。结果 所得微针机械强度足以穿透皮肤实现透皮给药。微针吸水性良好,使其在刺入皮肤后通过吸附溶胀和降解释放包合的米诺地尔。结论 以GelMA为基质的米诺地尔-GelMA生物可溶性微针具有生物相容性高、可缓释、靶向给药等优点。微针贴片便于携带,使用方便,与其他剂型相比有独特优势,具有较好的应用前景。

Preparation and Evaluation of Minoxidil-GelMA Bio-soluble Microneedles

OBJECTIVE To prepare minoxidil-Methacrylate Gelatin (GelMA) bio-soluble microneedles for the treatment of hair loss, and to characterize and evaluate obtained microneedles. METHODS Minoxidil-GelMA bio-soluble microneedles were prepared by using molding method and UV-crosslinking method. The morphology of microneedles(MNs) was characterized by using optical microscopy and fluorescence microscopy. The mechanical properties and the swelling rate of MNs were measured respectively. The effects of GelMA with different degree of crosslinking on the mechanical strength and water absorption of MNs were investigated. The effect of GelMA with different degree of crosslinking on drug release rate in vitro was also investigated. RESULTS The shape of microneedles was sharp, and the mechanical property could meet the requirement of skin penetration with finger pressing. And the mechanical strength of MNs was increased with the increase of crosslinking time. The drug release rate in vitro was reduced with the increase of crosslinking time. The tuned properties of MNs can fulfill the actual demand. CONCLUSION The microneedles show good water absorption, allowing the sustained release of encapsulated minoxidil through the swelling and degrading of MNs. Therefore, minoxidil-GelMA bio-soluble microneedles is an ideal type of preparation for the treatment of alopecia.