Biotrapping Ureolytic Bacteria on Sand to Improve the Efficiency of Biocementation
Biotrapping Ureolytic Bacteria on Sand to Improve the Efficiency of Biocementation
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DOI：
10.1021/acsami.3c13971
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发表时间：
2024-01-04
影响因子：
9.5
通讯作者：
Heveran，Chelsea
中科院分区：
文献类型：
--
作者：
Ugur，Gizem Elif;Rux，Kylee;Heveran，Chelsea
微生物诱导碳酸钙沉淀（MICP）已成为一种新技术，具有通过低温工艺生产建筑材料的潜力。在MICP中形成碳酸钙桥允许骨料颗粒的生物胶结以产生生物砖。目前的方法需要几个微生物脉冲和矿化介质来增加碳酸钙矿物的量并提高材料的强度，从而导致可持续性降低。提高强度发展效率的一种潜在技术涉及使用硅烷偶联剂如带正电荷的3-氨丙基-甲基-二乙氧基硅烷（APMDES）将细菌捕获在骨料表面上。这种处理通过静电相互作用将细菌捕获在沙子上，静电相互作用将带负电荷的细菌壁吸引到带正电荷的胺基团上。APMDES处理促进了细菌与砂的丰富和直接的关联，增加了砂上的尿素分解微生物的空间密度，并促进有效的初始碳酸钙沉淀。虽然微生物的活力受到损害的治疗，尿素水解的影响最小。APDES处理的砂比未处理的砂的强度获得更快。三次注射细菌和生物矿化介质使用APMDES处理过的沙子导致相同的强度增益为七次注射使用未经处理的沙子。用APMDES处理的较高强度不能用结构中碳酸钙增加来解释，而可能受到其他因素的影响，如砂粒之间碳酸钙桥的微观结构差异。总的来说，结合预处理方法，如胺硅烷偶联剂，通过生产具有更高效率和可持续性的材料，为生物矿化研究开辟了一条新的途径。
Microbially induced calcium carbonate precipitation (MICP) has emerged as a novel technology with the potential to produce building materials through lower-temperature processes. The formation of calcium carbonate bridges in MICP allows the biocementation of aggregate particles to produce biobricks. Current approaches require several pulses of microbes and mineralization media to increase the quantity of calcium carbonate minerals and improve the strength of the material, thus leading to a reduction in sustainability. One potential technique to improve the efficiency of strength development involves trapping the bacteria on the aggregate surfaces using silane coupling agents such as positively charged 3-aminopropyl-methyl-diethoxysilane (APMDES). This treatment traps bacteria on sand through electrostatic interactions that attract negatively charged walls of bacteria to positively charged amine groups. The APMDES treatment promoted an abundant and immediate association of bacteria with sand, increasing the spatial density of ureolytic microbes on sand and promoting efficient initial calcium carbonate precipitation. Though microbial viability was compromised by treatment, urea hydrolysis was minimally affected. Strength was gained much more rapidly for the APMDES-treated sand than for the untreated sand. Three injections of bacteria and biomineralization media using APMDES-treated sand led to the same strength gain as seven injections using untreated sand. The higher strength with APMDES treatment was not explained by increased calcium carbonate accrual in the structure and may be influenced by additional factors such as differences in the microstructure of calcium carbonate bridges between sand particles. Overall, incorporating pretreatment methods, such as amine silane coupling agents, opens a new avenue in biomineralization research by producing materials with an improved efficiency and sustainability.