title: Genetically Engineered Phage-Templated MnO2 Nanowires: Synthesis and Their Application in Electrochemical Glucose Biosensor Operated at Neutral pH Condition.
abstract: To conveniently obtain one-dimensional MnO2 nanowires (NWs) with controlled structure and unique properties for electron transfer, the genetically engineered M13 phages were used as templates for precise nucleation and growth of MnO2 crystals in filamentous phage scaffolds, via the spontaneous oxidation of Mn(2+) in alkaline solution. It was found that the morphology of NWs could be tailored by the surface charge of M13 mutants. MnO2 crystals were uniformly distributed on the surface of negatively charged tetraglutamate-fused phage (M13-E4), significantly different from irregular MnO2 agglomeration on the weakly negatively charged wild-type phage and positively charged tetraarginine-fused phage. The as-synthesized M13-E4@MnO2 NWs could catalyze the electro-oxidation of H2O2 at neutral pH. To demonstrate the superiority of the electrocatalytic activity in the solution containing plenty of chloride ions at neutral pH, both glucose oxidase and as-prepared MnO2 NWs were used for fabricating the glucose biosensor. The proposed biosensor showed a wide linear range (5 μM to 2 mM glucose), a low limit of detection of 1.8 μM glucose (S/N = 3), good interassay and intra-assay reproducibility and satisfactory storage stability. Due to the superiorities of synthesis and electrochemical performance, the as-prepared MnO2 NWs are promising for applications in electrocatalysis, electrochemical sensor, and supercapacitor.
authors.affiliation: Institute for Biosensing, and College of Chemistry and Chemical Engineering, Qingdao University , Qingdao 266071, China.|Laboratory for Biosensing, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences , 189 Songling Road, Qingdao 266101, China , and.
authors.forename: Lei
authors.initials: L
authors.lastname: Han
authors.affiliation: Institute for Biosensing, and College of Chemistry and Chemical Engineering, Qingdao University , Qingdao 266071, China.|Laboratory for Biosensing, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences , 189 Songling Road, Qingdao 266101, China , and.
authors.forename: Changxu
authors.initials: C
authors.lastname: Shao
authors.affiliation: Laboratory for Biosensing, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences , 189 Songling Road, Qingdao 266101, China , and.
authors.forename: Bo
authors.initials: B
authors.lastname: Liang
authors.affiliation: Institute for Biosensing, and College of Chemistry and Chemical Engineering, Qingdao University , Qingdao 266071, China.
authors.forename: Aihua
authors.initials: A
authors.lastname: Liu
mesh_terms: D001435:Bacteriophages / Q000235:genetics; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D004563:Electrochemistry; D005947:Glucose / Q000032:analysis*; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D017895:Manganese Compounds / Q000737:chemistry*; D053770:Nanowires / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D015203:Reproducibility of Results
chemical_list: D017895:Manganese Compounds; D010087:Oxides; D006861:Hydrogen Peroxide; D005947:Glucose; C016552:manganese dioxide
keywords: MnO2 nanowires; biotemplate synthesis; electrochemical glucose biosensor; neutral pH; phage display