Magnetic thermosensitive polymer composite carrier with target spacing for enhancing immobilized enzyme performance

• Published in: Enzyme and microbial technology 2021-10, Vol.150, p.109896-109896, Article 109896
• Main Authors: Tu, Hongyi, Zhang, Boyuan, Zhang, Xiayun, Zhao, Chunli, Li, Lin, Wang, Jianbin, Chen, Zhenbin, Wang, Pingbo, Li, Zhizhong
• Format: Article
• Language: English
• Subjects: Design; Fe3O4-grafted-poly N; N-diethyl acrylamide-block-poly β-Hydroxyethyl methacrylate-block-random copolymer of glycidyl methacrylate and methyl methacrylate (Fe3O4-g-PDEA-b-PHEMA-b-P(MMA-co-GMA)); Reversible-adaptive fragmentation chain transfer polymerization; Superparamagnetic nanocomposite carrier; Synthesis
• ISSN: 0141-0229; 1879-0909
• DOI: 10.1016/j.enzmictec.2021.109896

Scheme 1 The immobilization process of PGA on Magnetic Thermosensitive Polymer Composite Carrier Fe3O4-g-PDEA-b-PHEMA-b-P(MMA-co-GMA). [Display omitted] •Interesting design ideas with versatility.•Immobilization PGA shows 93.32 % high catalytic activity.•Immobilization PGA realizes homogeneous catalysis and heterogeneous magnetic separation.•Hydrophilic PHEMA and P(MMA-co-GMA) with adjustable target spacing help maintain high catalytic activity.•Small particle size carrier exhibits fast response rate. A novel magnetic thermosensitive polymer composite carrier with target spacing was developed. In this strategy, thermosensitive polymer grafted on magnetic Fe3O4 for enhancing immobilized penicillin G acylase (PGA) performance and introduce immobilized target spacing into magnetic carriers for the first time. Fe3O4 nanoparticles were synthesized by a reverse microemulsion method. The modifier used was the silane coupling agent γ-methylacryloxypropyl trimethoxysilane (KH570) and then reacting with a reversible-adaptive fragmentation chain transfer (RAFT) reagent, 2-cyano-2-propyldodecyl trithiocarbonate (CPDTC). The thermo-sensitive nanoparticle-composite carrier of Fe3O4-grafted-poly N, N-diethyl acrylamide-block-poly β-Hydroxyethyl methacrylate-block-random copolymer of glycidyl methacrylate and methyl methacrylate (Fe3O4-g-PDEA-b-PHEMA-b-P(MMA-co-GMA)) were synthesized by RAFT polymerization technique that used N, N-diethyl acrylamide (DEA), β-Hydroxyethyl methacrylate (HEMA), Glycidyl methacrylate (GMA) and Methyl methacrylate (MMA) as monomer, then which were employed as functional carriers for the immobilization of PGA. Within the carrier, the epoxy group of GMA segment was a target immobilization site for PGA and the introduction of MMA reflected the target space of immobilized PGA to improve catalytic activity and catalytic activity recovery rate of the immobilized PGA. Characterizations demonstrated that the triblock copolymers grafted Fe3O4 nanoparticles were successfully fabricated by the structure design. Besides, under these circumstances the enzyme activity (EA), enzyme loading capacity (ELC) and catalytic activity recovery ration (CAR) reached 31235 U/g, 128.39 mg/g and 93.32 %, respectively. The catalytic activity of immobilized PGA maintained 87.4 % of initial value and the recovery ratio (R) of immobilized PGA reached 96.22 % after recycling 12 times. Furthermore, the immobilized PGA exhibited advantages of low temperature homogeneous catalys