An ionically crosslinked hydrogel containing vancomycin coating on a porous scaffold for drug delivery and cell culture

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• 作者：Li Fang Zhang ; De Juan Yang ; He Chun Chen ; Rui Sun ; Liang Xu ; Zuo Chun Xiong ; Thirumala Govender ; Cheng Dong Xiong
• 关键词：Biodegradable polymers ; Porous scaffold ; Alginate hydrogel ; Coating ; Controlled release ; Cell culture
• 刊名：International Journal of Pharmaceutics
• 出版年：2008
• 出版时间：2 April 2008
• 年：2008
• 卷：353
• 期：1-2
• 页码：74-87
• 全文大小：2833 K

文摘

Alginate hydrogels were prepared with varying degrees of covalent cross-linking and different pore characteristics. Dehydrated scaffolds were compressed into smaller, temporary forms, introduced into the dorsal subcutaneous space of CD-1 mice by minimally invasive delivery through a 10 gauge angiocatheter and rehydrated in situ with a saline solution delivered through the same catheter. Ionically cross-linked calcium alginate gel served as a control. Specimens were harvested at 2, 6, 12 and 24 weeks to evaluate implant shape retention and volume, cell infiltration and calcification, and the presence of an inflammatory response.

Results:

A total of 90 scaffolds were implanted and 95 % were recovered at the site of injection. All of these scaffolds successfully rehydrated and 80 % recovered and maintained their original 3-dimensional shape for 6 months. Scaffold volume and tissue infiltration varied depending on the degree of alginate cross-linking. Highly cross-linked materials (20 % and 35 % ) demonstrated the best volume maintenance with the latter facilitating the most tissue infiltration. The inflammatory response was minimal except with the 80 % cross-linked material. Calcification was not observed in covalently cross-linked scaffolds. In contrast, 98 % of calcium alginate implants were calcified.

Conclusions:

Shape retaining porous hydrogels meet many of the requirements necessary for a successful injectable bulking agent and offer advantages over currently used agents.