带抗菌效能骨科内植物的研制与体外实验研究

Design and Experimental Study of an Anti-infective Orthopedic Implant

目的①研制一种可用于预防和治疗骨折内固定术后感染的骨科内植物。②对本带抗菌效能骨科内植物进行体外药物释放规律及持续时间测定,以了解其体外缓释规律及经过环氧乙烷灭菌对其抗菌效能的影响。方法在长约5cm,直径4mm的圆柱形不锈钢短棒上均匀涂布0.4g头孢唑啉钠,其外涂布丙烯酸树脂等多种高分子可降解有机物的混合物,即制成试验用带抗菌效能内植物。将带有涂层的8根不锈钢短棒随机分为2组,其中一组经环氧乙烷灭菌,将其分别置入10mlpH=7.40的PBS磷酸盐缓冲液中,并保持其处于37℃的环境中,用高效液相色谱法测量溶液中头孢唑啉钠的浓度变化及其有效抑菌时间。结果第1～2天本带抗菌效能骨科内植物所释放出的头孢唑啉钠保持一个较高的浓度,自第3天开始平缓的下降,第17天时8根试管最低浓度仍高达7.1μg/ml(头孢唑啉钠对金黄色葡萄球菌的最低抑菌浓度为0.1～6.3μg/ml),且环氧乙烷灭菌过程对其抗菌效能无任何影响。结论用本涂层方法制备的自带抗菌效能骨科内植物具有较强且持久的抗菌能力,可接受环氧乙烷灭菌,对防治开放性骨折术后感染具有良好的临床应用前景。

Objective ①To design an orthopedic implant with anti - infective fuaction, which can avoid the infection after internal fixation operation. ②To use HPLC for finding out drug - releasing regularity of the implant and whether ethylene oxide would lower the concentration of anti - bacterial agents on the implant. Methods Cefazolin of 0.4 g was smeared onto a cylindrical stainless steel of 5 cm long and 4 mm in diameter. Then some degradable organic matter was smeared on the Cefazolin. In this experiment, 8 pieces of cylindrical stainless steel bars were divided into two groups. One group was sterilized by ethylene oxide and the other group was not sterilized. The two groups were put into the phosphatic solution with the temperature remaining 37 ℃and pH = 7.40. HPLC was used to find the drug- releasing regularity of these implants, effective anti - infective time, and whether ethylene oxide would lower the concentration of anti- bacterial agents on these implants. Results The Cefazolin concentration in the phosphatic solution was considerably high in the first 2 days. After the 3rd day, the concentration was gently declined. In the 17th day, the Cefazolin concentration in the phosphatic solution remained 7.1μg/ml （the MIC of Cefazolin was 0.1 -6.3 μg/ml）, and the ethylene oxide had not lowered the concentration of anti - infective drugs on the implant. Conclusion The orthopedic implant we designed has the effective anti - infective function, which can allow the sterilization by ethylene oxide. These implants which have antiinfective function have a brilliant future to avoid infection after internal fixations.