a Jordan University of Science and Technology , Irbid , Jordan.
Pharm Dev Technol. 2018 Dec;23(10):986-997. doi: 10.1080/10837450.2016.1245319. Epub 2016 Nov 3.
Levodopa is a promising candidate for administration via the transdermal route because it exhibits a short plasma half-life and has a small window of absorption in the upper section of the small intestine. The aim of this study was to prepare stable levodopa transdermal patches. Both xanthan gum and Carbopol 971 polymers were selected with ethylcellulose constituting the backing layer of the prepared patches. The effect of adding β-cyclodextrin on the prepared patches was investigated. The uniformity in thickness, weight and content of the studied patches was acceptable. Physicochemical characterization revealed that there was no interaction between levodopa and the applied polymer. The results proved that levodopa precipitated as an amorphous form in carbopol patches. Controlled drug release was achieved for all the tested patches over a 6 h period. However, increased permeation was achieved for the carbopol patches. Although cyclodextrin did not enhance levodopa permeation, the stability study confirmed that levodopa stability was enhanced when complexed with β-cyclodextrin. The cumulative amount of drug released from carbopol patches is slightly higher than that of xanthan patches. The optimal stability was achieved in the carbopol/levodopa:β-cyclodextrin patch. The levodopa-β-cyclodextrin complex was successfully characterized using X-ray diffraction, NMR analysis and molecular dynamics simulations. In conclusion, carbopol/levodopa:β-cyclodextrin patches can be considered as a promising stable and effective transdermal drug-delivery system.
左旋多巴经皮给药是一种很有前途的候选药物，因为它的血浆半衰期短，在小肠上段的吸收窗口很小。本研究旨在制备稳定的左旋多巴透皮贴片。选择黄原胶和 Carbopol 971 聚合物作为乙基纤维素制备贴片的背衬层。考察了添加β-环糊精对制备贴片的影响。研究贴片的厚度、重量和含量均匀性均符合要求。物理化学特性研究表明，左旋多巴与应用的聚合物之间没有相互作用。结果表明，卡波姆贴片中的左旋多巴以无定形形式沉淀。所有测试贴片在 6 小时内均实现了药物的控释释放。然而，卡波姆贴片的渗透度增加。尽管环糊精没有增强左旋多巴的渗透度，但稳定性研究证实，当与β-环糊精络合时，左旋多巴的稳定性增强。从卡波姆贴片释放的累积药物量略高于黄原胶贴片。在卡波姆/左旋多巴：β-环糊精贴片达到最佳稳定性。成功地使用 X 射线衍射、NMR 分析和分子动力学模拟对左旋多巴-β-环糊精复合物进行了表征。总之，卡波姆/左旋多巴：β-环糊精贴片可以被认为是一种有前途的稳定有效的经皮给药系统。
