Gbureck Uwe, Vorndran Elke, Müller Frank A, Barralet Jake E
Department for Functional Materials in Medicine and Dentistry, University of Würzburg, Pleicherwall 2, Würzburg, Germany.
J Control Release. 2007 Sep 26;122(2):173-80. doi: 10.1016/j.jconrel.2007.06.022. Epub 2007 Jun 30.
The aim of this study was to investigate the adsorption and desorption kinetics of antibiotics to microporous bioceramics fabricated by a novel low temperature 3D powder direct printing process. The adsorption of vancomycin, ofloxacin and tetracycline onto hydroxyapatite, brushite and monetite showed a linear correlation with the drug concentration in the immersion solution, whereas a non-linear relationship was found between the immersion time and the amount of adsorbed drug. Differences in the total amount of adsorbed drugs were correlated to the specific surface areas of the matrices, which varied between 2.4-13.1 m(2)/g. Normalised drug loadings were found to be in the range of 1.5-1.8 mg/m(2) for vancomycin and ofloxacin, whereas higher loads of up to 5-7 mg/m(2) were obtained for tetracycline. Vancomycin and ofloxacin were rapidly released into PBS buffer within 1-2 days, while tetracycline showed a much slower release rate of approximately 25% after 5 days of immersion. Additional polymer impregnation of the drug loaded matrix with PLA/PGA polymer solutions enabled the release kinetics to be delayed such that sustained release was achieved in polymer ceramic biocomposites.
本研究的目的是研究抗生素对通过新型低温3D粉末直接打印工艺制备的微孔生物陶瓷的吸附和解吸动力学。万古霉素、氧氟沙星和四环素在羟基磷灰石、透钙磷石和磷酸氢钙上的吸附与浸泡溶液中的药物浓度呈线性相关，而浸泡时间与吸附药物量之间呈非线性关系。吸附药物总量的差异与基质的比表面积相关，比表面积在2.4 - 13.1 m²/g之间变化。发现万古霉素和氧氟沙星的归一化载药量在1.5 - 1.8 mg/m²范围内，而四环素的载药量更高，可达5 - 7 mg/m²。万古霉素和氧氟沙星在1 - 2天内迅速释放到PBS缓冲液中，而四环素在浸泡5天后显示出约25%的慢得多的释放速率。用聚乳酸/聚乙醇酸聚合物溶液对载药基质进行额外的聚合物浸渍能够延迟释放动力学，从而在聚合物陶瓷生物复合材料中实现持续释放。
