Uppsala University, Department of Pharmacy, Uppsala, Sweden.
J Pharm Pharmacol. 2011 Oct;63(10):1265-73. doi: 10.1111/j.2042-7158.2011.01339.x. Epub 2011 Aug 16.
The aim of this study was to investigate skin permeation rates of a drug substance when applied in novel gel formulations with catanionic aggregates.
Reference gel without catanionic aggregates was compared with formulations with catanionic aggregates composed of tetracaine and either sodium dodecyl sulphate (SDS) or capric acid. Carbomer and SoftCAT were used to compare the effect of different gel types to elucidate if physically cross-linked, 'self-destructing' systems had benefits compared with classical, covalently cross-linked, gels.
The rheological investigation showed that the interactions between the SoftCAT polymer and tetracaine/SDS aggregates were stronger than when the tetracaine/capric acid aggregates were used. The skin permeation was measured ex vivo in horizontal Ussing chambers and the permeation of tetracaine was significantly lower when formulations with tetracaine/SDS aggregates were applied (P < 0.001), but not statistically different from the reference when capric acid was used.
No morphological differences could be distinguished between the skin samples exposed to the different formulations or the reference. Skin permeation was compared with silicone sheet permeation and the results indicated that silicone sheets could be used as a model of skin when using these formulations.
本研究旨在考察应用具有双离子聚集体的新型凝胶制剂时药物的透皮速率。
将不含双离子聚集体的参考凝胶与由局麻药和十二烷基硫酸钠（SDS）或癸酸组成的双离子聚集体制剂进行比较。使用卡波姆和 SoftCAT 来比较不同凝胶类型的效果，以阐明与经典的共价交联凝胶相比，物理交联的“自毁”系统是否具有优势。
流变学研究表明，SoftCAT 聚合物与局麻药/SDS 聚集体之间的相互作用强于局麻药/癸酸聚集体。在水平 Ussing 室中进行了离体皮肤渗透研究，当使用局麻药/SDS 聚集体制剂时，局麻药的渗透明显降低（P < 0.001），但当使用癸酸时，与参比制剂没有统计学差异。
暴露于不同制剂或参比制剂的皮肤样本之间未观察到形态学差异。将皮肤渗透与硅酮片渗透进行了比较，结果表明在使用这些制剂时，硅酮片可以作为皮肤模型。
