title: Hemin-block copolymer micelle as an artificial peroxidase and its applications in chromogenic detection and biocatalysis.
abstract: Following an inspiration from the fine structure of natural peroxidases, such as horseradish peroxidase (HRP), an artificial peroxidase was constructed through the self-assembly of diblock copolymers and hemin, which formed a functional micelle with peroxidase-like activity. The pyridine moiety in block copolymer poly(ethylene glycol)-block-poly(4-vinylpyridine) (PEG-b-P4VP) can coordinate with hemin, and thus hemin is present in a five-coordinate complex with an open site for binding substrates, which mimics the microenvironment of heme in natural peroxidases. The amphiphilic core-shell structure of the micelle and the coordination interaction of the polymer to the hemin inhibit the formation of hemin μ-oxo dimers, and thereby enhance the stability of hemin in the water phase. Hemin-micelles exhibited excellent catalytic performance in the oxidation of phenolic and azo compounds by H2O2. In comparison with natural peroxidases, hemin-micelles have higher catalytic activity and better stability over wide temperature and pH ranges. Hemin-micelles can be used as a detection system for H2O2 with chromogenic substrates, and they anticipate the possibility of constructing new biocatalysts tailored to specific functions.
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials, Ministry of Education, Institute of Polymer Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University , Tianjin 300071, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Qu
authors.forename: Liangliang
authors.initials: L
authors.lastname: Shen
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Chai
authors.forename: Chen
authors.initials: C
authors.lastname: Jing
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yingli
authors.initials: Y
authors.lastname: An
authors.forename: Linqi
authors.initials: L
authors.lastname: Shi
mesh_terms: D001391:Azo Compounds / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D001557:Benzenesulfonates / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D003124:Colorimetry / Q000379:methods*; D004355:Drug Stability; D006427:Hemin / Q000737:chemistry / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D008823:Micelles; D008956:Models, Chemical; D009195:Peroxidase / Q000737:chemistry / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry*; D012972:Sodium Hydroxide
chemical_list: D001391:Azo Compounds; D001557:Benzenesulfonates; D008823:Micelles; D011145:Polyvinyls; C546916:poly(ethylene glycol)-block-poly(4-vinylpyridine); D011092:Polyethylene Glycols; D012972:Sodium Hydroxide; D006427:Hemin; D006861:Hydrogen Peroxide; D009195:Peroxidase; C014722:2-naphthol orange
keywords: artificial peroxidase; block copolymer; coordination; hemin; micelle