Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Helwan University, Helwan, Cairo, 11790 Egypt.
Drug Deliv. 2010 Jul;17(5):282-7. doi: 10.3109/10717541003706257.
The objectives of this research were to prepare ribavirin niosomes and evaluate the influence of niosomal encapsulation on drug liver targeting in rats. Ribavirin niosomes were prepared by the thin film hydration method using span 60, cholesterol, and dicetyl phosphate in molar ratios of (1:1:0), (4:2:0), (1:1:0.1), and (4:2:1). The prepared niosomes were characterized in vitro for vesicle size, drug entrapment, drug release profiles, and vesicular stability at refrigerator temperature. The results indicated that niosomes of the molar ratio (4:2:1) had a significantly (p < 0.05) higher entrapment percentage of ribavirin than the other molar ratios, moreover, they revealed sustained release characteristics as well as longer release pattern than other niosomal formulations. Accordingly, niosomes of molar ratio (4:2:1) was selected for in vivo liver targeting study. Separately, niosomal ribavirin dispersion and free ribavirin solution were administered as a single dose of 30 mg/kg by intraperitoneal injection into two groups of rats to compare the liver ribavirin concentration. The obtained results show that the niosomal formulation significantly increased ribavirin liver concentration (6-fold) in comparison with ribavirin-free solution. Based on the previous results, the use of niosomes as a drug delivery system for ribavirin has significant liver targeting properties, this is expected to improve the efficacy of low doses of ribavirin and minimize its toxic side-effects at higher doses.
本研究的目的是制备利巴韦林脂质体，并考察脂质体包封对大鼠肝靶向的影响。采用薄膜水化法，以摩尔比为（1:1:0）、（4:2:0）、（1:1:0.1）和（4:2:1）的司盘 60、胆固醇和双十六烷基磷酸酯制备利巴韦林脂质体。对所得脂质体进行体外考察，包括囊泡粒径、药物包封率、药物释放特性以及冷藏温度下的囊泡稳定性。结果表明，摩尔比为（4:2:1）的脂质体具有显著（p < 0.05）更高的利巴韦林包封率，此外，与其他脂质体制剂相比，其具有持续释放特性和更长的释放模式。因此，选择摩尔比为（4:2:1）的脂质体用于体内肝靶向研究。此外，将脂质体利巴韦林分散体和游离利巴韦林溶液分别以 30 mg/kg 的剂量通过腹腔注射给药至两组大鼠中，以比较肝内利巴韦林浓度。结果表明，与利巴韦林游离溶液相比，脂质体制剂显著增加了肝内利巴韦林浓度（6 倍）。基于上述结果，脂质体作为利巴韦林的药物传递系统具有显著的肝靶向特性，有望提高低剂量利巴韦林的疗效，并降低高剂量时的毒性副作用。
