Microorganism-mediated, CTAB-directed aggregation of Au nanostructures around Escherichia coli cells: Towards enhanced Au recovery through coordination of cell-CTAB–ascorbic acid
Microorganism-mediated, CTAB-directed aggregation of Au nanostructures around Escherichia coli cells: Towards enhanced Au recovery through coordination of cell-CTAB–ascorbic acid
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DOI：
10.1016/j.seppur.2014.07.016
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发表时间：
2014-09
影响因子：
8.6
通讯作者：
Haixian Yang;Liqin Lin;T. Odoom-Wubah;Dengpo Huang;Daohua Sun;Jiale Huang;Qingbiao Li
中科院分区：
文献类型：
--
作者：
Haixian Yang;Liqin Lin;T. Odoom-Wubah;Dengpo Huang;Daohua Sun;Jiale Huang;Qingbiao Li
本文首次证明了微生物介导的十六烷基三甲基溴化铵（CTAB）定向（MCD）在大肠杆菌细胞（ECCs）周围聚集金纳米结构，以提高水相haucl4中金的回收率。由于细胞- ctab -抗坏血酸（AA）的协同作用，一维Au纳米结构在ECCs周围生长，诱导Au与ECCs快速聚集。当ECC用量和haucl4浓度匹配时，CTAB和AA浓度对沉淀的影响不显著。随着CTAB浓度的增加，Au的回收率降低，而较高的Au回收率需要最低的AA浓度。结合ecc的Au离子在细胞表面被还原成Au核，提供了优先成核的位置。同时，溶液中的自由配体取代阴离子被还原为Au原子，作为Au纳米结构生长的Au源。这项工作为通过金纳米结构的工程化来提高金的回收效率提供了一条新的途径。
In this paper, a microorganism-mediated, cetyltrimethylammonium bromide (CTAB)-directed (MCD) aggregation of Au nanostructures aroundEscherichia colicells (ECCs) for enhanced Au recovery, from aqueous HAuCl4is demonstrated for the first time. Owing to the coordination of cell-CTAB–ascorbic acid (AA), one dimensional Au nanostructures grew around the ECCs, inducing the rapid aggregation of Au and the ECCs. The concentrations of CTAB and AA had insignificant effect on the precipitation if the ECC dosage and HAuCl4concentration were matched. The Au recovery efficiency decreased with increasing CTAB concentration, while a minimum AA concentration was required for higher Au recovery efficiency. The ECC-binding Au ions were reduced to form Au nuclei over the cell surface that provided preferential nucleation sites. Meanwhile, the free ligand-substituted anions in the solution were reduced to Au atoms that served as Au source for growing the Au nanostructures around the ECCs. This work exemplifies a new avenue to enhance the efficiency of recovering Au through the engineering of Au nanostructures.