Mesa Ruddy L M, Villa Javier E L, Khan Sabir, Peixoto Rafaella R Alves, Morgano Marcelo A, Gonçalves Luís Moreira, Sotomayor Maria D P T, Picasso Gino
Laboratory of Physical Chemistry Research, Faculty of Sciences, National University of Engineering, Lima 15333, Peru.
Institute of Chemistry, State University of São Paulo (UNESP), Araraquara, SP 14800-060, Brazil.
Nanomaterials (Basel). 2020 Dec 17;10(12):2541. doi: 10.3390/nano10122541.
Methylmercury (MeHg) is a mercury species that is very toxic for humans, and its monitoring and sorption from environmental samples of water are a public health concern. In this work, a combination of theory and experiment was used to rationally synthesize an ion-imprinted polymer (IIP) with the aim of the extraction of MeHg from samples of water. Interactions among MeHg and possible reaction components in the pre-polymerization stage were studied by computational simulation using density functional theory. Accordingly, 2-mercaptobenzimidazole (MBI) and 2-mercaptobenzothiazole (MBT), acrylic acid (AA) and ethanol were predicted as excellent sulfhydryl ligands, a functional monomer and porogenic solvent, respectively. Characterization studies by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) revealed the obtention of porous materials with specific surface areas of 11 m g (IIP-MBI-AA) and 5.3 m g (IIP-MBT-AA). Under optimized conditions, the maximum adsorption capacities were 157 µg g (for IIP-MBI-AA) and 457 µg g (for IIP-MBT-AA). The IIP-MBT-AA was selected for further experiments and application, and the selectivity coefficients were MeHg/Hg (0.86), MeHg/Cd (260), MeHg/Pb (288) and MeHg/Zn (1510), highlighting the material's high affinity for MeHg. The IIP was successfully applied to the sorption of MeHg in river and tap water samples at environmentally relevant concentrations.
甲基汞（MeHg）是一种对人类毒性极强的汞物种，对其在环境水样中的监测及吸附是一个公共卫生问题。在这项工作中，采用理论与实验相结合的方法合理合成了一种离子印迹聚合物（IIP），目的是从水样中萃取甲基汞。在预聚合阶段，利用密度泛函理论通过计算模拟研究了甲基汞与可能的反应组分之间的相互作用。据此，预测2-巯基苯并咪唑（MBI）和2-巯基苯并噻唑（MBT）、丙烯酸（AA）和乙醇分别为优良的巯基配体、功能单体和致孔溶剂。通过扫描电子显微镜（SEM）和布鲁诺尔-埃米特-泰勒（BET）进行的表征研究表明，获得了比表面积分别为11 m²/g（IIP-MBI-AA）和5.3 m²/g（IIP-MBT-AA）的多孔材料。在优化条件下，最大吸附容量分别为157 μg/g（IIP-MBI-AA）和457 μg/g（IIP-MBT-AA）。选择IIP-MBT-AA进行进一步实验和应用，其选择性系数分别为MeHg/Hg（0.86）、MeHg/Cd（260）、MeHg/Pb（288）和MeHg/Zn（1510），突出了该材料对甲基汞的高亲和力。该IIP成功应用于环境相关浓度下河水和自来水样中甲基汞的吸附。
