Kassem M A, Abdel Rahman A A, Ghorab M M, Ahmed M B, Khalil R M
Department of Pharmaceutical Technology, National Research Center, Dokki, Cairo, Egypt.
Int J Pharm. 2007 Aug 1;340(1-2):126-33. doi: 10.1016/j.ijpharm.2007.03.011. Epub 2007 Mar 12.
Poorly-water-soluble compounds are difficult to develop as drug products using conventional formulation techniques. The use of nanotechnology to formulate poorly-water-soluble drugs as nanosuspensions offers the opportunity to address many of the deficiencies associated with this class of molecules. In the present study, the high pressure homogenization method used to prepare nanosuspensions of three practically insoluble glucocorticoid drugs; hydrocortisone, prednisolone and dexamethasone. The effect of particle size in the micron and nano-size ranges as well as the effect of viscosity of the nanosuspension on the ocular bioavailability was studied by measuring the intraocular pressure of normotensive Albino rabbits using shiØetz tonometer. The results show that compared to solution and micro-crystalline suspensions it is a common feature of the three drugs that the nanosuspensions always enhance the rate and extent of ophthalmic drug absorption as well as the intensity of drug action. In the majority of cases nanosuspensions extend the duration of drug effect to a significant extent. The data presented confirms that nanosuspensions differ from micro-crystalline suspensions and solution as ophthalmic drug delivery systems and that the differences are statistically, highly to very highly significant. The results confirm also the importance of viscosity of nanosuspension especially in increasing the duration of drug action.
使用传统制剂技术将水溶性差的化合物开发成药品很困难。利用纳米技术将水溶性差的药物制成纳米混悬液，为解决与这类分子相关的许多缺陷提供了契机。在本研究中，采用高压均质法制备了三种几乎不溶性糖皮质激素药物（氢化可的松、泼尼松龙和地塞米松）的纳米混悬液。通过使用施-茨眼压计测量正常血压白化兔的眼压，研究了微米和纳米尺寸范围内的粒径以及纳米混悬液的粘度对眼部生物利用度的影响。结果表明，与溶液和微晶混悬液相比，这三种药物的共同特点是纳米混悬液总能提高眼科药物的吸收速率和程度以及药物作用强度。在大多数情况下，纳米混悬液能显著延长药物作用持续时间。所呈现的数据证实，作为眼科药物递送系统，纳米混悬液与微晶混悬液和溶液不同，且这些差异在统计学上具有高度到非常高度的显著性。结果还证实了纳米混悬液粘度的重要性，尤其是在延长药物作用持续时间方面。
