Rudolfs Cimdins Riga Biomaterials Innovations and Development Centre of Riga Technical University, Pulka 3, LV-1007 Riga, Latvia.
Mater Sci Eng C Mater Biol Appl. 2015 Apr;49:106-113. doi: 10.1016/j.msec.2014.12.075. Epub 2014 Dec 24.
Among calcium phosphate biomaterials, calcium phosphate bone cements (CPCs) have attracted increased attention because of their ability of self-setting in vivo and injectability, opening the new opportunities for minimally invasive surgical procedures. However, any surgical procedure carries potential inflammation and bone infection risks, which could be prevented combining CPC with anti-inflammatory drugs, thus overcoming the disadvantages of systemic antibiotic therapy and controlling the initial burst and total release of active ingredient. Within the current study α-tricalcium phosphate based CPCs were prepared and it was found that decreasing the solid to liquid phase ratio from 1.89g/ml to 1.23g/ml, initial burst release of vancomycin within the first 24h increased from 40.0±2.1% up to 57.8±1.2% and intrinsic properties of CPC were changed. CPC modification with vancomycin loaded poly(lactic acid) (PLA) microcapsules decreased the initial burst release of drug down to 7.7±0.6%, while only 30.4±1.3% of drug was transferred into the dissolution medium within 43days, compared to pure vancomycin loaded CPC, where 100% drug release was observed already after 12days. During the current research a new approach was found in order to increase the drug bioavailability. Modification of CPC with novel PLA/vancomycin microcapsules loaded and coated with nanosized hydroxyapatite resulted in 85.3±3.1% of vancomycin release within 43days.
在磷酸钙生物材料中，磷酸钙骨水泥（CPC）因其在体内的自凝固能力和可注射性而受到越来越多的关注，为微创手术开辟了新的机会。然而，任何手术都有潜在的炎症和骨感染风险，如果将 CPC 与抗炎药物结合使用，可以预防这些风险，从而克服全身抗生素治疗的缺点，并控制有效成分的初始突释和完全释放。在目前的研究中，制备了基于α-磷酸三钙的 CPC，并发现将固液比从 1.89g/ml 降低至 1.23g/ml，万古霉素的初始突释率在最初 24 小时内从 40.0±2.1%增加到 57.8±1.2%，并且 CPC 的固有性质发生了变化。用载万古霉素的聚乳酸（PLA）微胶囊修饰 CPC 可将药物的初始突释率降低至 7.7±0.6%，而在 43 天内仅有 30.4±1.3%的药物转移到溶解介质中，相比之下，纯载万古霉素的 CPC 在 12 天后就已经观察到 100%的药物释放。在目前的研究中，发现了一种提高药物生物利用度的新方法。用载有纳米羟基磷灰石的新型 PLA/万古霉素微胶囊对 CPC 进行修饰和包被，可在 43 天内释放 85.3±3.1%的万古霉素。
