可生物降解高分子微针的制作及透皮应用

透皮给药相比于传统的给药方式,具有更多的优势．但是,皮肤的角质层能够阻止外源性物质的侵犯,限制了透皮给药系统的应用．为此,基于微针的透皮给药系统的提出增大了透皮给药系统的应用范围．首先,采用MEM技术制作单晶硅微针．接下来,提出一种新颖、简单而且经济的方法快速制作聚乳酸微针．通过理论分析及有限元分析微针的力学性能,表明微针有足够的强度．体外透皮实验表明,未经微针处理的皮肤,钙黄绿素10h的累计渗透量只有0．17±0．07 μg／cm2;手动进针处理的皮肤只达到4．54±1．17 μg／cm2,比未用微针处理的皮肤增加了30倍;经过进针器处理的皮肤,各个时间点的渗透量均有显著性提高（P〈0．05）,渗透量达到45．37±5．80 μg／cm2,比未用微针处理的皮肤增加了300倍．所有的结果都表明,本实验室制备可降解的聚乳酸微针的方法新颖、快速且经济,而且对于透皮给药系统来说具有很大的潜在价值．     

Solid Carriers for Improved Solubility of Glipizide in Osmotically Controlled Oral Drug Delivery System

The purpose of this study was to increase the solubility of glipizide (gli) by solid dispersions SDs technique with polyvinylpyrrolidone (PVP) in aqueous media. The gli–PVP solid dispersion systems was prepared by physical mixing or spray drying method, and characterized by differential scanning calorimetry (DSC), X-ray powder diffraction (XRD) analysis, Fourier transformation-infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The elementary osmotic pumps (EOPs) were prepared with gli–PVP complex and the effect of the PVP percentages on the enhancing of gli dissolution rate was studied. The influences of various parameters e.g., drug- PVP ratio, level of solubility modifier, coating weight gain and diameter of drug releasing orifice on drug release profiles were also investigated. The solubility and dissolution rates of gli were significantly increased by solid dispersion using spray dried method as well as their physical mixture. The obtained results indicated that gli–PVP solid dispersion system has suitable solubility behavior in EOP tablets.