title: Partially reduced graphene oxide-gold nanorods composite based bioelectrode of improved sensing performance.
abstract: The present work proposes partially reduced graphene oxide-gold nanorods supported by chitosan (CH-prGO-AuNRs) as a potential bioelectrode material for enhanced glucose sensing. Developed on ITO substrate by immobilizing glucose oxidase on CH-prGO-AuNRs composite, these CH-prGO-AuNRs/ITO bioelectrodes demonstrate high sensitivity of 3.2 µA/(mg/dL)/cm(2) and linear range of 25-200 mg/dL with an ability to detect as low as 14.5 mg/dL. Further, these CH-prGO-AuNRs/ITO based electrodes attest synergistiacally enhanced sensing properties when compared to simple graphene oxide based CH-GO/ITO electrode. This is evident from one order higher electron transfer rate constant (Ks) value in case of CH-prGO-AuNRs modified electrode (12.4×10(-2) cm/s), in contrast to CH-GO/ITO electrode (6×10(-3) cm/s). Additionally, very low Km value [15.4 mg/dL(0.85 mM)] ensures better binding affinity of enzyme to substrate which is desirable for good biosensor stability and resistance to environmental interferences. Hence, with better loading capacity, kinetics and stability, the proposed CH-prGO-AuNRs composite shows tremendous potential to detect several bio-analytes in the coming future.
authors.affiliation: Department of Zoology, Banaras Hindu University, Varanasi 221005, India.
authors.forename: Narsingh R
authors.initials: NR
authors.lastname: Nirala
authors.affiliation: Department of Physics, Banaras Hindu University, Varanasi 221005, India.
authors.forename: Shiju
authors.initials: S
authors.lastname: Abraham
authors.affiliation: Department of Zoology, Banaras Hindu University, Varanasi 221005, India.
authors.forename: Vinod
authors.initials: V
authors.lastname: Kumar
authors.affiliation: Department of Metallurgical Engineering, IIT (BHU), Varanasi 221005, India.
authors.forename: Shobhit A
authors.initials: SA
authors.lastname: Pandey
authors.affiliation: Department of Zoology, Banaras Hindu University, Varanasi 221005, India.
authors.forename: Umakant
authors.initials: U
authors.lastname: Yadav
authors.affiliation: School of Materials Science and Technology, IIT (BHU), Varanasi 221005, India.
authors.forename: Monika
authors.initials: M
authors.lastname: Srivastava
authors.affiliation: Department of Physics, Mahila Mahavidyalaya (MMV), Banaras Hindu University, Varanasi 221005, India.
authors.forename: S K
authors.initials: SK
authors.lastname: Srivastava
authors.affiliation: CSIR-National Physical Laboratory, New Delhi, India.
authors.forename: Vidya Nand
authors.initials: VN
authors.lastname: Singh
authors.affiliation: School of Biotechnology, Banaras Hindu University, Varanasi 221005, India.
authors.forename: Arvind M
authors.initials: AM
authors.lastname: Kayastha
authors.affiliation: Department of Physics, Banaras Hindu University, Varanasi 221005, India. Electronic address: anchalbhu@gmail.com.
authors.forename: Anchal
authors.initials: A
authors.lastname: Srivastava
authors.affiliation: Department of Zoology, Banaras Hindu University, Varanasi 221005, India. Electronic address: pssaxena@rediffmail.com.
authors.forename: Preeti S
authors.initials: PS
authors.lastname: Saxena
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D048271:Chitosan / Q000737:chemistry; D004563:Electrochemistry; D004566:Electrodes; D005947:Glucose / Q000032:analysis; D005949:Glucose Oxidase / Q000737:chemistry / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D017971:Tin Compounds / Q000737:chemistry
chemical_list: D010087:Oxides; D017971:Tin Compounds; C109984:indium tin oxide; D006046:Gold; D006108:Graphite; D048271:Chitosan; D005949:Glucose Oxidase; D005947:Glucose
keywords: Chitosan; Composite; Electrochemical biosensors; Flavin adenine dinucleotide (FAD); Glucose K(m); Gold nanorods; K(s); Partially reduced graphene oxide