title: One-pot synthesis of 3-dimensional reduced graphene oxide-based hydrogel as support for microbe immobilization and BOD biosensor preparation.
abstract: We report a hydrothermal method to prepare reduced graphene oxide (rGO)-based hydrogel (Gel(rGONR)), using neutral red (NR) to mediate the assembly of rGO sheets and tune the pore size of Gel(rGONR). A series of techniques including scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy and BET were employed to characterize the physico-chemical properties of Gel(rGONR). A large pore size of up to 20 µm and interconnected porous structure of Gel(rGONR) were obtained. Gel(rGONR) was used as a support for immobilizing microbe (denoted as Gel(rGONR-M)), which showed ~3.3 times more load mass of microbe than commonly used supports (i.e., activated carbon and carbon fiber felt) and 2.5 times higher biodegradation efficiency (BE) than carbon fiber felt. Further use of Gel(rGONR-M) as a biocatalyst for establishing a BOD biosensor exhibits a linear range of 2-64 mg O L(-1) and a detection limit 0.4 mg O L(-1) for glucose-glutamic acid (GGA). Moreover, our proposed BOD detection strategy shows a long-term viability over one year and stability up to 2 months with a relative standard deviation of 2.1%. Our results demonstrated the great potential of employing Gel(rGONR) as a microbe-immobilization support for biosensor development.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China.
authors.forename: Ling
authors.initials: L
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China.
authors.forename: Junfeng
authors.initials: J
authors.lastname: Zhai
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China.
authors.forename: Chengzhou
authors.initials: C
authors.lastname: Zhu
authors.affiliation: School of Science, Changchun Institute of Technology, Changchun, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Gao
authors.affiliation: School of Science, Changchun Institute of Technology, Changchun, PR China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China.
authors.forename: Yanchao
authors.initials: Y
authors.lastname: Han
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China. Electronic address: dongsj@ciac.jl.cn.
authors.forename: Shaojun
authors.initials: S
authors.lastname: Dong
mesh_terms: D001422:Bacterial Adhesion / Q000502:physiology*; D001681:Biological Assay / Q000295:instrumentation; D057919:Biological Oxygen Demand Analysis / Q000295:instrumentation*; D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry*; D020100:Hydrogels / Q000138:chemical synthesis*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry
chemical_list: D020100:Hydrogels; D010087:Oxides; D006108:Graphite
keywords: BOD biosensor; Biochemical oxygen demand; Biodegradation efficiency; Microbe immobilization; Neutral red; Reduced graphene oxide-hydrogel