Efficient biodegradation may offer a solution for the treatment of nitro-aromatic compounds (NACs) with toxicity, mutagenicity and persistence in the environment. In this study, dopamine (DA) functionalized magnetic nanoparticles with biocompatibility and hydrophilicity were synthesized and utilized for the immobilization of nitro-aromatic compounds degrading psychrophile Psychrobacter sp. ANT206 harboring the cold-adapted nitroreductase. The prepared nanocarriers were characterized using multiple methods. The highest immobilization yield of cells immobilized by Fe₃O₄@SiO₂@DA was 90.67% under the optimized conditions of 10 °C, pH 7.5, 2 h and cell/support 1.2 mg/mg, and the activity recovery was 89.41%. In addition, the obtained immobilized cells displayed excellent salinity stability and reusability. Moreover, immobilized P. sp. ANT206 strains showed remarkable biodegradation capability on nitrobenzene and p-nitrophenol. This study introduced those novel Fe₃O₄@SiO₂@DA nanoparticles could be applied as ideal and low-cost nanocarriers for the immobilization of cells and large-scale bioremediation of hazardous NACs with perspective applications under low temperature.

有效的生物降解可以为处理具有毒性、致突变性和在环境中持久存在的硝基芳香族化合物（NAC）提供解决方案。在本研究中，合成了具有生物相容性和亲水性的多巴胺（DA）功能化磁性纳米粒子，并将其用于固定降解嗜冷菌Psychrobacter sp . 的硝基芳香族化合物。ANT206 含有冷适应硝基还原酶。使用多种方法对制备的纳米载体进行了表征。_{Fe 3} O ₄ @SiO ₂ @DA在10℃、pH 7.5、2 h、细胞/载体1.2 mg/mg的优化条件下固定化细胞最高固定化率为90.67%，活性回收率为89.41% 。此外，获得的固定化细胞表现出优异的盐度稳定性和可重复使用性。此外，固定化的P。sp。ANT206菌株对硝基苯和对硝基苯酚表现出显着的生物降解能力。本研究介绍了这些新型Fe ₃ O ₄ @SiO ₂ @DA纳米颗粒可作为理想且低成本的纳米载体，用于细胞固定和有害NAC的大规模生物修复，并在低温下具有广阔的应用前景。