Mu Tingzhen, Zhao Jixiang, Guan Yueping, Tian Jiangnan, Yang Maohua, Guo Chen, Xing Jianmin
Key Laboratory of Green Process and Engineering, State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.
School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
Biotechnol Lett. 2017 Jun;39(6):865-871. doi: 10.1007/s10529-017-2317-2. Epub 2017 Mar 15.
Thialkalivibrio versutus D301 cells were immobilized on FeO nanoparticles (NPs) synthesized by an improved chemical coprecipitation method and modified with 3-aminopropyltriethoxysilane (APTES), then the immobilized cells were used in sulfur oxidation.
The prepared FeO-APTES NPs had a narrow size distribution (10 ± 2 nm) and were superparamagnetic, with a saturation magnetization of 60.69 emu/g. Immobilized cells had a saturation magnetization of 34.95 emu/g and retained superparamagnetism. The optimum conditions for cell immobilization were obtained at pH 9.5 and 1 M Na. The immobilization capacity of FeO-APTES NPs was 7.15 g DCW/g-NPs that was 2.3-fold higher than that of FeO NPs. The desulfurization efficiency of the immobilized cells was close to 100%, having the same sulfur oxidation capacity as free cells. Further, the immobilized cells could be reused at least eight times, retaining more than 85% of their desulfurization efficiency.
Immobilization of cells with the modified magnetic NPs efficiently increased cell controllability, have no effect on their desulfurization activity and could be effectively used in large-scale industrial applications.
将嗜碱硫杆菌D301细胞固定在通过改进的化学共沉淀法合成并用3-氨丙基三乙氧基硅烷（APTES）改性的FeO纳米颗粒（NPs）上，然后将固定化细胞用于硫氧化。
制备的FeO-APTES NPs粒径分布窄（10±2nm），具有超顺磁性，饱和磁化强度为60.69emu/g。固定化细胞的饱和磁化强度为34.95emu/g，并保留超顺磁性。细胞固定化的最佳条件为pH 9.5和1M Na。FeO-APTES NPs的固定化容量为7.15g DCW/g-NPs，比FeO NPs高2.3倍。固定化细胞的脱硫效率接近100%，具有与游离细胞相同的硫氧化能力。此外，固定化细胞可重复使用至少八次，保留其脱硫效率的85%以上。
用改性磁性纳米颗粒固定化细胞可有效提高细胞可控性，对其脱硫活性无影响，可有效用于大规模工业应用。
