改性Fe_3O_4纳米颗粒固定醋酸杆菌及稳定性分析

Acetobacter Immobilized by Modified Fe_3O_4 Magnetic Nanoparticles and Analysis of Its Stability

目的:优化Fe3O4纳米颗粒固定醋酸杆菌的条件,探讨Fe3O4纳米颗粒作为微生物固定化载体的可行性。方法:以柠檬酸铵处理获得改性的Fe3O4纳米颗粒,分别研究改性和未改性Fe3O4纳米颗粒在不同pH、固定化时间、Fe3O4和醋酸杆菌的重量比条件下醋酸杆菌的固定化率;通过多批次使用,研究固定化菌的操作稳定性。结果:在pH为4.5,固定时间40min,m(醋酸杆菌):m(Fe3O4)=1:1,m(柠檬酸铵)/m(Fe3O4)=3%的条件下,改性Fe3O4纳米颗粒对醋酸杆菌的固定化效果最好;当重复试验10次后,固定化菌的固定化率仍保持在70%以上。结论:经柠檬酸铵改性的Fe3O4纳米颗粒对醋酸杆菌的固定效果好,稳定性高,固定化微生物可以重复利用,具有较好的实际利用价值。

Objective： The conditions of immobilized Acetobacter by modifiedFe3O4magnetic nanoparticles were optimized, the feasibility of Fe3O4 nanoparticles as immobilized carrier was discussed. Method：Using the modifiedFe3O4 magnetic nanoparticles by Ammonium citrate as immobilized carrier, immobilized rate was studied under different levels of pH, fixed time, the weight ratio of Acetobacter to Fe3O4. The stability of immobilized Acetibacter（modified） was analysised by reusing. Result：4. 5 of pH ,40 minutes of fixed time, 1：1 of the weight ra- tio of Acetobacter to Fe304 ,3% of the weight ratio of Ammonium Citrate to Fe3O4 ,were selected as the best immobilized conditions. The fixed rate was still more than 70% reusing ten times. Conclusion：The modifiedFe3O4 magnetic nanopartieles by Ammonium Citrate had a better ability immobilizing Acetobacter. The immobilized Acetobacter could be reused, so it had a good value in application.