Natural Tubular Halloysite as Drug Carrier: Effect of Organosilane Modification and Thermal Treatment

作     者：YUAN Peng TAN Daoyong Annabi-Bergaya Faza LIU Dong LIU Hongmei 

作者机构：CAS Key Laboratory of Mineralogy and MetallogenyGuangzhou Institute of GeochemistryChinese Academy of Sciences University of Chinese Academy of Sciences Centre de Recherche sur la Matière DiviséeCNRS-Université d'OrléansOrléans 45071France 

出 版 物：《矿物学报》 (Acta Mineralogica Sinica)

年 卷 期：2013年第33卷第S1期

页      面：131-131页

核心收录：

学科分类：081902[工学-矿物加工工程] 0819[工学-矿业工程] 08[工学] 

主　　题：halloysite ibuprofen drug delivery organosilane modification thermal treatment 

摘      要：Naturally occurring tubular halloysite is a potential drug carrier because of the significant deposit, unique mesoscopic (2-50 nm) or even macroscopic (50 nm) lumen, and excellent biocompatibility. The drugs loaded on halloysite exhibited slow release under the diffusion limitation by the halloysite nanotube. However, due to the weak interaction between halloysite and guest, the loading capacity of halloysite was relatively low. This drawback severely limits the application of halloysite as carrier in pharmaceutics. In this study, the performance of halloysite as carrier for ibuprofen (IBU) loading was investigated for the first time. The effects of 3-aminopropyltriethoxysilane (APTES) modification and thermal treatment of halloysite on the loading and release of IBU were also studied. The purified halloysites were heated at 120 ℃ and 400 ℃ (labeled as Hal/120 and Hal/400), and then modified with APTES (labeled as Hal/120-A and Hal/400-A). The loading of IBU was achieved by soaking method (labeled as IBU-Hal/120, IBU-Hal/400, IBU-Hal/120-A, and IBU-Hal/400-A.). The in vitro drug delivery assays were performed in phosphate buffer solution. IBU was loaded mainly into the lumen and partially on the external surface of halloysite. The order of IBU contents was as follows: IBU-Hal/400-A (14.8wt%) IBU-Hal/120-A (12.7wt%) IBU-Hal/400 (11.8wt%) IBU-Hal/120 (11.7wt%). The IBU was initially anchored to the surface hydroxyl groups of halloysite by hydrogen bonding, followed by further bonding of IBU with the anchored IBU to form hydrogen-bonded aggregates. The APTES modification of halloysite promoted the loading of IBU by introducing a strong affinity through electrostatic attraction between the introduced aminopropyl groups of APTES and the carboxyl groups of IBU. Thermal treatment at 400°C did not destroy the tubular morphology or the crystal structure of halloysite and had little effect on IBU loading in unmodified halloysite. However, thermal treatment by reducing