Bone regeneration with recombinant human bone morphogenetic protein-2 (rhBMP-2) using absorbable collagen sponges (ACS): Influence of processing on ACS characteristics and formulation
Bone regeneration with recombinant human bone morphogenetic protein-2 (rhBMP-2) using absorbable collagen sponges (ACS): Influence of processing on ACS characteristics and formulation
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DOI：
10.1081/pdt-100101374
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发表时间：
1999-08-01
影响因子：
3.4
通讯作者：
Biron, R
中科院分区：
文献类型：
--
作者：
Friess, W;Uludag, H;Biron, R
研究了三种外科植入性可吸收胶原海绵(ACS)的三个参数(质量、与CH2O的交联度和ETO灭菌)的变异性。对用重组人骨形态发生蛋白-2(rhBMP-2)溶液浸泡的海绵进行了pH值、电导率和rhBMP-2沉淀的分析。建立了用三硝基苯磺酸测定胶原海绵中游离氨基的方法。CH2O暴露240分钟后，游离氨基减少到80%。相比之下，用差示扫描量热仪(DSC)测定的海绵在磷酸盐缓冲盐水浸泡后的变性温度从48摄氏度上升到55摄氏度，这表明由于交联剂的作用更强。随后用ETO灭菌后，游离氨基的数量显著减少(约为未灭菌对照的33%)，与先前的CH2O处理无关。然而，灭菌海绵的变性温度比未灭菌的材料平均低5摄氏度。与CH2O暴露相反，与ETO的强烈反应似乎削弱了胶原结构。海绵对胶原酶的抵抗力与胶原的交联度有关，但经灭菌后略有降低。此外，用水浸泡的ACS经灭菌处理后，其pH值显著提高。蛋白质沉淀是pH和盐浓度的函数，但仅受胶原蛋白的影响不大。结果表明，为了避免重组人骨形态发生蛋白-2的沉淀，必须限制ACS的重量。
The effects of variability in three parameters (mass, cross-linking with CH2O, and EtO sterilization) of three surgically implantable absorbable collagen sponges (ACS) were studied. Sponges soaked with recombinant human bone morphogenetic protein-2 (rhBMP-2) solution were analyzed for pH, conductivity, and rhBMP-2 precipitation. A method using trinitrobenzenesulfonic acid was developed to quantify the free amino groups of the collagen sponge. With up to 240 min exposure to CH2O, the amount of free amino groups was reduced to 80%. In comparison, the denaturation temperature as determined by differential scanning calorimetry (DSC) after the sponges were soaked with phosphate-buffered saline, increased from 48 to 55 degrees C, indicating stronger interactions due to cross-linking. Subsequent sterilization with EtO caused a marked decrease in the amount of free amino groups (approximately 33% of nonsterilized controls) independent of previous CH2O treatment. However, the denaturation temperature was on average 5 degrees C lower in sterilized sponges than in nonsterilized material. In contrast to CH2O exposure, the strong reaction with EtO appeared to weaken the collagen structure. Resistance of the sponge to collagenase correlated with the degree of collagen cross-linking but was slightly reduced by sterilization. In addition, the pH of ACS soaked with water was substantially increased by sterilization. Protein precipitation was a function of pH and salt concentration but there was no effect due to collagen alone. Results indicated that ACS weight has to be limited to avoid rhBMP-2 precipitation.