蛋白质对建筑材料中的生物凝固的影响
Elvis Baffoe1, Edward Dauer2, Ali Ghahremaninezhad1
1Department of Civil and Architectural Engineering, University of Miami, Coral Gables, FL 33146, USA.
iScience
|January 18, 2024
概括
蛋白质通过屏蔽酶和形成凝网络来增强碳酸沉在水泥环境中的结合. 这提高了材料的性能,而瓦特里特是主要的晶体形式.
科学领域:
- 材料科学 材料科学 材料科学
- 生物化学 生物化学
- 土木工程 土木工程是指土木工程.
背景情况:
- 酶诱导碳酸沉 (EICP) 是一种有前途的材料改造方法.
- 了解蛋白质相互作用对于优化EICP在复杂环境中至关重要,如水泥系统.
- 在水泥环境中的高pH值可能会对酶活性和降水产生负面影响.
研究的目的:
- 在水泥环境中研究蛋白质对EICP的结合特性和微观结构的影响.
- 在高pH条件下评估蛋白质对尿酶活性的保护作用.
- 描述蛋白质修饰EICP过程中形成的晶体相.
主要方法:
- 对EICP沉物的蛋白质修饰.
- 评估沉物与玻璃和水泥糊表面的结合.
- 在水泥状况下进行酶活性测定.
- 福利埃变换红外光谱 (FTIR),扫描电子显微镜 (SEM),热重力学分析 (TGA) 和X射线衍射 (XRD) 用于材料特征.
主要成果:
- 与对照组相比,蛋白质修饰沉物对表面的结合有所改善.
- 蛋白质部分保护尿酶免受高pH的影响,减轻活性减少.
- 蛋白质-Ca2+复合促进了CaCO3核和结晶.
- 瓦特里特是水泥环境中占主导地位的CaCO3多态,与去离子化水中的石不同.
结论:
- 蛋白质显著提高了EICP在水泥环境中的结合能力.
- 尿酶的蛋白屏蔽是保持高pH环境中的降水效率的关键.
- 蛋白质诱导的凝网络作为有效的核化场所,影响CaCO3多态形成 (瓦特里特).
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