Departmento de Microbiologia, Univerisidad de Granada, Campus de Fuentenueva s/n, 18002, Granada, Spain.
Departmento de Mineralogia, Universidad de Granada, Campus de Fuentenueva s/n, 18002, Granada, Spain.
Ecotoxicol Environ Saf. 2020 Apr 1;192:110307. doi: 10.1016/j.ecoenv.2020.110307. Epub 2020 Feb 15.
An increasing concern for natural resources preservation and environmental safety is the removal of heavy metals from contaminated water. It is essential to develop simple procedures that use ecofriendly materials with high removal capacities. In this context, we have synthesized a new hybrid material in which eggshell membranes (ESMs) act as nucleation sites for magnetite nanoparticles (MNPs) precipitation in the presence of an external magnetic field. As a result, ESM was transformed into a magnetic biomaterial (MESM) in order to combine the Pb adsorption abilities of both MNPs and ESM and to facilitate collection of the bioadsorbant using an external magnetic field. This green co-precipitation method produced long strands of bead-like 50 nm superparamagnetic MNPs decorating the ESM fibers. When MESM were incubated in Pb(NO) solutions, the hybrid material displayed a 2.5-fold increase in binding constant with respect to that of ESM alone, and a 10-fold increased capacity to remove Pb ions from aqueous solution. The manufactured MESMs present a maximum loading capacity of 0.066 ± 0.009 mg Pb/mg MNPs at 25 °C, which is increased up to 0.15 ± 0.05 mg Pb/mg MNPs at 45 °C. Moreover, the MESM system is very stable, since incubation in 1% HCl solution resulted in rapid Pb desorption, while MNP release from the MESM during the same period was negligible. Altogether, these results suggest that MESM could be utilized as an efficient nanoremediation agent for separation/removal of heavy metal ions or other charged pollutants from contaminated waters, with facile recovery for recycling.
人们越来越关注自然资源的保护和环境安全，因此需要开发从受污染的水中去除重金属的简单方法，这些方法最好使用具有高去除能力的环保材料。在此背景下，我们合成了一种新型杂化材料，该材料中蛋壳膜（ESM）在外磁场的作用下充当了磁铁矿纳米颗粒（MNP）沉淀的成核位点。结果，ESM 被转化为磁性生物材料（MESM），以结合 MNP 和 ESM 的 Pb 吸附能力，并利用外磁场方便地收集生物吸附剂。这种绿色共沉淀法产生了长串珠状的 50nm 超顺磁 MNP，其装饰在 ESM 纤维上。当 MESM 被孵育在 Pb(NO)溶液中时，与单独的 ESM 相比，杂化材料的结合常数增加了 2.5 倍，从水溶液中去除 Pb 离子的容量增加了 10 倍。所制造的 MESM 在 25°C 时的最大负载容量为 0.066±0.009mg Pb/mg MNP，在 45°C 时增加到 0.15±0.05mg Pb/mg MNP。此外，MESM 系统非常稳定，因为在 1%HCl 溶液中孵育会导致 Pb 快速解吸，而在同一时期 MNP 从 MESM 中的释放可以忽略不计。总之，这些结果表明，MESM 可以用作从受污染的水中分离/去除重金属离子或其他带电污染物的有效纳米修复剂，并且易于回收再利用。
