title: Multifunctional glucose biosensors from Fe₃O₄ nanoparticles modified chitosan/graphene nanocomposites.
abstract: Novel water-dispersible and biocompatible chitosan-functionalized graphene (CG) has been prepared by a one-step ball milling of carboxylic chitosan and graphite. Presence of nitrogen (from chitosan) at the surface of graphene enables the CG to be an outstanding catalyst for the electrochemical biosensors. The resulting CG shows lower ID/IG ratio in the Raman spectrum than other nitrogen-containing graphene prepared using different techniques. Magnetic Fe3O4 nanoparticles (MNP) are further introduced into the as-synthesized CG for multifunctional applications beyond biosensors such as magnetic resonance imaging (MRI). Carboxyl groups from CG is used to directly immobilize glucose oxidase (GOx) via covalent linkage while incorporation of MNP further facilitated enzyme loading and other unique properties. The resulting biosensor exhibits a good glucose detection response with a detection limit of 16 μM, a sensitivity of 5.658 mA/cm(2)/M, and a linear detection range up to 26 mM glucose. Formation of the multifunctional MNP/CG nanocomposites provides additional advantages for applications in more clinical areas such as in vivo biosensors and MRI agents.
authors.affiliation: Lab of Nanoscale Biosensing and Bioimaging, Institute of Advanced Materials for Nano-Bio Applications, School of Ophthalmology &Optometry, Wenzhou Medical University, 270 Xueyuan Xi Road, Wenzhou, Zhejiang 325027, China.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Lab of Nanoscale Biosensing and Bioimaging, Institute of Advanced Materials for Nano-Bio Applications, School of Ophthalmology &Optometry, Wenzhou Medical University, 270 Xueyuan Xi Road, Wenzhou, Zhejiang 325027, China.
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Li
authors.affiliation: Lab of Nanoscale Biosensing and Bioimaging, Institute of Advanced Materials for Nano-Bio Applications, School of Ophthalmology &Optometry, Wenzhou Medical University, 270 Xueyuan Xi Road, Wenzhou, Zhejiang 325027, China.
authors.forename: Ruitao
authors.initials: R
authors.lastname: Zou
authors.affiliation: Lab of Nanoscale Biosensing and Bioimaging, Institute of Advanced Materials for Nano-Bio Applications, School of Ophthalmology &Optometry, Wenzhou Medical University, 270 Xueyuan Xi Road, Wenzhou, Zhejiang 325027, China.
authors.forename: Huizi
authors.initials: H
authors.lastname: Wu
authors.affiliation: Lab of Nanoscale Biosensing and Bioimaging, Institute of Advanced Materials for Nano-Bio Applications, School of Ophthalmology &Optometry, Wenzhou Medical University, 270 Xueyuan Xi Road, Wenzhou, Zhejiang 325027, China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Shi
authors.affiliation: Lab of Nanoscale Biosensing and Bioimaging, Institute of Advanced Materials for Nano-Bio Applications, School of Ophthalmology &Optometry, Wenzhou Medical University, 270 Xueyuan Xi Road, Wenzhou, Zhejiang 325027, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Yu
authors.affiliation: 1] Lab of Nanoscale Biosensing and Bioimaging, Institute of Advanced Materials for Nano-Bio Applications, School of Ophthalmology &Optometry, Wenzhou Medical University, 270 Xueyuan Xi Road, Wenzhou, Zhejiang 325027, China [2] Advanced Cytometry Labs, ARC Center of Excellence for Nanoscale BioPhotonics, Macquarie University, Sydney, NSW 2109, Australia.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D048271:Chitosan / Q000737:chemistry; D003287:Contrast Media / Q000737:chemistry; D004800:Enzymes, Immobilized / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry*; D005947:Glucose / Q000032:analysis*; D005949:Glucose Oxidase / Q000378:metabolism; D006108:Graphite / Q000737:chemistry; D057230:Limit of Detection; D008279:Magnetic Resonance Imaging / Q000379:methods; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*
chemical_list: D003287:Contrast Media; D004800:Enzymes, Immobilized; D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; C000499:ferric oxide; D006108:Graphite; D048271:Chitosan; D005949:Glucose Oxidase; D005947:Glucose