Synthesis of fibrous and non-fibrous mesoporous silica magnetic yolk –shell microspheres as recyclable supports for immobilization of Candida rugosa lipase

Publication date: August 2017 Source:Enzyme and Microbial Technology, Volume 103 Author(s): Zafar Ali, Lei Tian, Baoliang Zhang, Nisar Ali, Muhammad Khan, Qiuyu Zhang The mesoporous yolk–shell nanoparticles (MYSNs), with a movable Fe3O4 core inside the hollow capsules, with two different morphologies (1) Fe3O4@SiO2@hollow@fibrous SiO2 (Yolk Shell-1) (2) Fe3O4@SiO2@hollow@mesoporousSiO2 (Yolk Shell-2) were fabricated as carriers for Candida rugosa lipase (CRL) immobilization, through a template-assistant selectively etching method. Firstly the hydrophilic Fe3O4 nanoparticles were synthesized according to the solvothermal method. Then, SiO2 shell was coated on the Fe3O4 nanoparticle surface by a sol–gel reaction. Subsequently, the resorcinol farmaldehyde (RF) shell was covered on the surface of as-prepared Fe3O4@SiO2 composites and sandwiched Fe3O4@SiO2@RF composites were formed, which were finally provided with mesoporous fibrous (KCC) in the Yolk Shell-1 and mesoporous Silica in the Yolk Shell-2(Non fibrous). After selectively etching CTAB and the middle RF layer, the two kinds of yolk/shells composites were obtained. By utilization of their large and open mesopores (20–50nm) with good surface area (457.78–625.54m2/g,) CRL was immobilized after amino functionalization using glutaraldehyde as a linker. The ICRL on Y.S-1, Y.S-2 showed good loading (797–501mg/g) and enzyme activity of (1503–837U/g) respectively. Thermal stability, resistance to pH, recycling ...
Source: Enzyme and Microbial Technology - Category: Biotechnology Source Type: research