Wang Binbin, Zhu Yutong, Dong Wenbo, Wang Chaojun, Yang Luyao, Fan Yujie, Sun Taoyu, Shan Yi, Wu Zhongkuan, He Feng
College of Environment, Zhejiang University of Technology, Hangzhou 310014, China.
Institute of Environmental Processes and Pollution control and School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China.
Environ Sci Technol. 2025 Jul 15;59(27):14089-14102. doi: 10.1021/acs.est.5c00497. Epub 2025 Jul 1.
Sulfidated nanoscale zerovalent iron (S-nZVI) is a promising material for the remediation of chlorinated hydrocarbons (CHCs) in groundwater, offering enhanced reactivity and selectivity over unmodified nanoscale zerovalent iron (nZVI). However, integrating S-nZVI with bioremediation using organohalide-respiring bacteria (OHRB) poses potential cytotoxicity challenges. This study investigated the differential impacts of S-nZVI and nZVI on the dechlorination activity of strain 195 ( 195), a representative OHRB. Key factors, including hydrogen evolution reaction (HER), pH, Fe concentration, and nanoparticle-cell interactions, were assessed. S-nZVI exhibited significantly lower cytotoxicity compared to nZVI, primarily due to the reduced nanoparticle adhesion to 195 cell membranes, attributed to its negative surface charge rather than to the milder physicochemical disturbances in the culture medium. S-nZVI minimally disrupted extracellular polymeric substances (EPS), preserving cell integrity, and provided a more sustained hydrogen supply under hydrogen-limited conditions. Limited contact experiments confirmed that the reduced cytotoxicity of S-nZVI stemmed from lower contact toxicity rather than its intrinsic chemical reactivity. This study unveils the mechanisms underlying the interaction between S-nZVI and OHRB, highlighting S-nZVI's potential for safer and more effective abiotic-biotic remediation strategies. The findings provide a scientific basis for optimizing combined remediation approaches for comprehensive CHCs cleanup.
硫化纳米零价铁（S-nZVI）是一种很有前景的用于修复地下水中氯代烃（CHCs）的材料，与未改性的纳米零价铁（nZVI）相比，它具有更高的反应活性和选择性。然而，将S-nZVI与利用有机卤呼吸细菌（OHRB）进行的生物修复相结合会带来潜在的细胞毒性挑战。本研究调查了S-nZVI和nZVI对代表性OHRB菌株195脱氯活性的不同影响。评估了包括析氢反应（HER）、pH值、铁浓度和纳米颗粒与细胞相互作用等关键因素。与nZVI相比，S-nZVI表现出显著更低的细胞毒性，这主要是由于纳米颗粒对195细胞膜的附着力降低，这归因于其负表面电荷，而非培养基中较温和的物理化学干扰。S-nZVI对细胞外聚合物（EPS）的破坏最小，保持了细胞完整性，并在氢气受限条件下提供了更持续的氢气供应。有限接触实验证实，S-nZVI细胞毒性降低源于较低的接触毒性，而非其内在化学反应性。本研究揭示了S-nZVI与OHRB相互作用的潜在机制，突出了S-nZVI在更安全、更有效的非生物-生物修复策略中的潜力。这些发现为优化综合CHCs清理的联合修复方法提供了科学依据。
