Department of Chemistry, Marquette University, P. O. Box 1881, Milwaukee, Wisconsin, 53201.
J Biomed Mater Res A. 2013 Nov;101(11):3266-77. doi: 10.1002/jbm.a.34636. Epub 2013 Apr 18.
Hydroxyapatite (HAp) is often used as a bone-implant material because it is biocompatible and osteoconductive. However, HAp possesses poor rheological properties and it is inactive against disease-causing microbes. To improve these properties, we developed a green method to synthesize multifunctional composites containing: (1) cellulose (CEL) to impart mechanical strength; (2) chitosan (CS) to induce antibacterial activity thereby maintaining a microbe-free wound site; and (3) HAp. In this method, CS and CEL were co-dissolved in an ionic liquid (IL) and then regenerated from water. HAp was subsequently formed in situ by alternately soaking [CEL+CS] composites in aqueous solutions of CaCl2 and Na2 HPO4 . At least 88% of IL used was recovered for reuse by distilling the aqueous washings of [CEL+CS]. The composites were characterized using FTIR, XRD, and SEM. These composites retained the desirable properties of their constituents. For example, the tensile strength of the composites was enhanced 1.9 times by increasing CEL loading from 20% to 80%. Incorporating CS in the composites resulted in composites which inhibited the growth of both Gram positive (MRSA, S. aureus and VRE) and Gram negative (E. coli and P. aeruginosa) bacteria. These findings highlight the potential use of [CEL+CS+HAp] composites as scaffolds in bone tissue engineering.
羟基磷灰石（HAp）常被用作骨植入材料，因为它具有生物相容性和骨诱导性。然而，HAp 的流变性较差，对致病微生物没有活性。为了改善这些性能，我们开发了一种绿色方法来合成含有以下成分的多功能复合材料：（1）纤维素（CEL），赋予机械强度；（2）壳聚糖（CS），诱导抗菌活性，从而保持无微生物的伤口部位；和（3）HAp。在该方法中，CS 和 CEL 共同溶解在离子液体（IL）中，然后从水中再生。HAp 随后通过在 CaCl2 和 Na2 HPO4 的水溶液中交替浸泡 [CEL+CS] 复合材料原位形成。通过蒸馏 [CEL+CS] 的水洗液，至少回收了 88%的 IL 以供重复使用。使用 FTIR、XRD 和 SEM 对复合材料进行了表征。这些复合材料保留了其组成成分的理想性质。例如，通过将 CEL 的负载从 20%增加到 80%，复合材料的拉伸强度提高了 1.9 倍。在复合材料中加入 CS 导致复合材料抑制革兰氏阳性（MRSA、金黄色葡萄球菌和 VRE）和革兰氏阴性（大肠杆菌和铜绿假单胞菌）细菌的生长。这些发现突出了 [CEL+CS+HAp] 复合材料作为骨组织工程支架的潜在用途。
