依诺肝素钠在聚甲基丙烯酸甲酯骨水泥中稳定性的研究

Stability of enoxaparin sodium in polymethyl methacrylate bone cement

目的观察聚甲基丙烯酸甲酯(PMMA)骨水泥的聚合反应过程及释放的热量对加入其中的依诺肝素钠(ES)稳定性的影响。方法将8 000 AXaIU依诺肝素钠加入到40 g Palacos?R PMMA骨水泥中,依照ISO5833:2002《外科植入物——丙稀酸类树脂骨水泥》标准制作依诺肝素钠骨水泥圆柱体试模,用pH7.4 Tris-HCL缓冲液浸提24 h。测定浸提液的抗栓活性和抗凝活性并与标准依诺肝素钠溶液进行对比。结果8 000 AXaIU依诺肝素钠加入40 g Palacos?R PMMA骨水泥中得到的释放体系。24 h抗Ⅹa因子活性为0.847 AXaIU/ml,具有明显的抗栓活性;能显著延长兔血浆复钙时间,表现出良好的抗凝活性。ES纯粉和ES-PMMA骨水泥经75 ℃高温处理10 min,抗Ⅹa因子活性和抗凝活性均没有明显变化。结论ES能够耐受PMMA骨水泥聚合反应及放热过程,保持自身的抗栓抗凝作用基本不变,具有复合入PMMA骨水泥的潜力。

Objective To investigate the polymerization process of polymethyl methacrylate (PMMA) bone cement, and the effects of exothermy on the stability of enoxaparin sodium (ES) added. Methods 8 000 AXaIU enoxaparin sodium was added to 40 g Palacos? R PMMA bone cement and the enoxparin sodium cement cylindrical test specimen was prepared according to ISO5833: 2002 "Surgical Implants-Acrylic Resin Bone Cement" standard. It was leached with pH 7.4 Tris-HCL buffer for 24 h. The antithrombotic activity and anticoagulant activity of the extract were determined and compared with the standard enoxaparin sodium dissolution. Results The release system of 8000 AXaIU enoxaparin sodium added to 40 g Palacos? R PMMA bone cement had an anti-Ⅹa factor activity of 0.847 AXaIU/ml for 24 h, which had obvious antithrombotic activity, could significantly prolong rabbit plasma recalcification time and exert good anticoagulant activity. After the ES pure powder or ES-PMMA bone cement was treated at 75 ℃ for 10 min, there was no significant change in anti-Ⅹa factor activity or anticoagulant activity. Conclusion ES can withstand PMMA bone cement polymerization and exothermic process, maintain its own anti-thrombation and anticoagulant effect, and has the potential to be compounded into PMMA bone cement.