Host鈥揋uest Chemistry of Dendrimer鈥揇rug Complexes: 7. Formation of Stable Inclusions between Acetylated Dendrimers and Drugs Bearing Multiple Charges

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• 作者：Min Fang ; Jiahai Zhang ; Qinglin Wu ; Tongwen Xu ; Yiyun Cheng
• 刊名：The Journal of Physical Chemistry B
• 出版年：2012
• 出版时间：March 15, 2012
• 年：2012
• 卷：116
• 期：10
• 页码：3075-3082
• 全文大小：427K
• 年卷期：v.116,no.10(March 15, 2012)
• ISSN：1520-5207

文摘

Drug molecules bearing multiple charges usually form precipitates with cationic dendrimers, which presents a challenge during the preparation of dendrimer inclusions for these drugs. In the present study, fully acetylated polyamidoamine (PAMAM) dendrimers were proposed as stable vehicles for drug molecules bearing two negative charges such as Congo red and indocyanine green. NMR techniques including ¹H NMR and ¹H-¹H NOESY were used to characterize the host鈥揼uest chemistry of acetylated dendrimer and these guest molecules. The cationic PAMAM dendrimer was found to form a precipitate with Congo red and indocyanine green, but the acetylated one avoided the formation of cross-linking structures in aqueous solutions. NOESY studies revealed the encapsulation of Congo red and indocyanine green within the interior cavities of PAMAM dendrimers at mild acidic conditions and acetylated dendrimers show much stronger ability to encapsulate the guest molecules than cationic ones. Also, UV鈥搗is鈥揘IR studies suggest that acetylated dendrimers significantly improve the photostability of indocyanine green and prevent the formation of indocyanine green J-aggregates in aqueous solutions. The present study provides a new insight into dendrimer-based host鈥揼uest systems, especially for those guest molecules bearing multiple charges.