title: Multifunctional Janus hematite-silica nanoparticles: mimicking peroxidase-like activity and sensitive colorimetric detection of glucose.
abstract: The design and engineering of multifunctional nanostructures with multiple components and synergistic properties are in urgent demand for variety of acceptable biosensing platforms, enabling users to fulfill multiple tasks in a single nanosystem. Herein, we report using an asymmetric hematite-silica hybrid of Janus γ-Fe2O3/SiO2 nanoparticles (JFSNs) as a multifunctional biosensing platform for sensitive colorimetric detection of H2O2 and glucose. It was demonstrated that JFSNs exhibit an intrinsic peroxidase-like catalytic activity. Compared with natural enzyme, JFSNs nanoenzymes could be used over a wider range of pH and temperatures and were more stable over time. Importantly, besides its excellent catalytic activity, the asymmetric properties of the Janus nanoparticle enable it to form the multiple functional utilities for various biosensing applications, including the ease of surface modification without deactivation of catalytic activity and recoverable use by magnetic separation. Thus, we utilized JFSNs with glucose oxidase (GOx) immobilization for glucose-sensitive colorimetric detection, which exhibited both catalytic activity of glucose oxidase and peroxidase with high selectivity and acceptable reproducibility. By combining these two analysis systems into Janus particles, an all-in-one and reusable sensor for blood glucose was formed and has the capability for determination of glucose in complex samples such as serum. These results suggest that such Janus nanosystems have the potential to construct robust nanoarchitecture with multiple functionalities for various biosensing applications.
authors.forename: Chang
authors.initials: C
authors.lastname: Lu
authors.forename: Xiangjiang
authors.initials: X
authors.lastname: Liu
authors.affiliation: §Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Li
authors.forename: Fang
authors.initials: F
authors.lastname: Yu
authors.forename: Longhua
authors.initials: L
authors.lastname: Tang
authors.affiliation: §Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
authors.forename: Yanjie
authors.initials: Y
authors.lastname: Hu
authors.forename: Yibin
authors.initials: Y
authors.lastname: Ying
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002384:Catalysis; D003124:Colorimetry / Q000379:methods*; D004800:Enzymes, Immobilized / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry*; D005947:Glucose / Q000032:analysis*; D005949:Glucose Oxidase / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000032:analysis; D057230:Limit of Detection; D053758:Nanoparticles / Q000737:chemistry*; D009195:Peroxidase / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D005290:Ferric Compounds; C000499:ferric oxide; D012822:Silicon Dioxide; D006861:Hydrogen Peroxide; D005949:Glucose Oxidase; D009195:Peroxidase; D005947:Glucose
keywords: Janus nanoparticle; colorimetric biosensor; glucose; hematite−silica; hydrogen peroxide