Krishnaiah Y S R, Satyanarayana V, Bhaskar P
Department of Pharmaceutical Sciences, Andhra University, Visakhapatnam, India.
Pharmazie. 2002 Dec;57(12):842-7.
The aim of the present investigation was to study the effect of limonene on in vitro permeation of nicardipine hydrochloride across the excised rat abdominal skin from a 2% w/w hydroxypropyl cellulose (HPC) gel. The HPC gel formulations containing 1% w/w of nicardipine hydrochloride and selected concentrations of limonene (0% w/w to 12% w/w) were prepared, and subjected to in vitro permeation of the drug through excised rat abdominal epidermis. The drug content in the gels was found to be uniform and the drug was found to be stable in the HPC gel formulations. The permeation flux of nicardipine hydrochloride across rat epidermis was increased markedly by the addition of limonene to the HPC gels. A maximum flux was observed (246 +/- 1 micrograms/cm2/h) with an enhancement ratio of about 8 when limonene was incorporated at a concentration of 4% w/w. However, there was no further increase in the permeability of nicardipine hydrochloride beyond 4% w/w of limonene. The DSC and FT-IR data indicated that limonene increased the permeability of nicardipine hydrochloride across the rat epidermis by partial extraction of lipids in the stratum corneum. The results suggest that limonene may be useful for enhancing the skin permeability of nicardipine hydrochloride from transdermal therapeutic system containing HPC gel as a reservoir.
本研究的目的是考察柠檬烯对盐酸尼卡地平从2%（w/w）羟丙基纤维素（HPC）凝胶中透过离体大鼠腹部皮肤的体外渗透作用。制备了含1%（w/w）盐酸尼卡地平及选定浓度柠檬烯（0%（w/w）至12%（w/w））的HPC凝胶制剂，并使其进行药物透过离体大鼠腹部表皮的体外渗透实验。发现凝胶中的药物含量均匀，且药物在HPC凝胶制剂中稳定。向HPC凝胶中添加柠檬烯可显著提高盐酸尼卡地平透过大鼠表皮的渗透通量。当柠檬烯以4%（w/w）的浓度加入时，观察到最大通量（246±1μg/cm²/h），增强比约为8。然而，当柠檬烯浓度超过4%（w/w）时，盐酸尼卡地平的渗透性没有进一步增加。差示扫描量热法（DSC）和傅里叶变换红外光谱（FT-IR）数据表明，柠檬烯通过部分提取角质层中的脂质增加了盐酸尼卡地平透过大鼠表皮的渗透性。结果表明，柠檬烯可能有助于提高含HPC凝胶作为储库的透皮治疗系统中盐酸尼卡地平的皮肤渗透性。
