title: In situ synthesis of biomolecule encapsulated gold-cross-linked poly(ethylene glycol) nanocomposite as biosensing platform: a model study.
abstract: In situ synthesis of poly(ethylene glycol) (PEG) hydrogels containing gold nanoparticles (AuNPs) and glucose oxidase (GOx) enzyme by photo-induced electron transfer process was reported here and applied in electrochemical glucose biosensing as the model system. Newly designed bionanocomposite matrix by simple one-step fabrication offered a good contact between the active site of the enzyme and AuNPs inside the network that caused the promotion in the electron transfer properties that was evidenced by cyclic voltammetry as well as higher amperometric biosensing responses in comparing with response signals obtained from the matrix without AuNPs. As well as some parameters important in the optimization studies such as optimum pH, enzyme loading and AuNP amount, the analytical characteristics of the biosensor (AuNP/GOx) were examined by the monitoring of chronoamperometric response due to the oxygen consumption through the enzymatic reaction at -0.7 V under optimized conditions at sodium acetate buffer (50 mM, pH 4.0) and the linear graph was obtained in the range of 0.1-1.0 mM glucose. The detection limit (LOD) of the biosensor was calculated as 0.06 mM by using the signal to noise ratio of 3. Moreover, the presence of AuNPs was visualized by TEM. Finally, the biosensor was applied for glucose analysis for some beverages and obtained data were compared with HPLC as the reference method to test the possible matrix effect due to the nature of the samples.
authors.affiliation: Ege University, Faculty of Science, Biochemistry Department, Bornova, 35100 Izmir, Turkey.
authors.forename: Dilek
authors.initials: D
authors.lastname: Odaci
authors.forename: Muhammet U
authors.initials: MU
authors.lastname: Kahveci
authors.forename: Elif L
authors.initials: EL
authors.lastname: Sahkulubey
authors.forename: Caglar
authors.initials: C
authors.lastname: Ozdemir
authors.forename: Tamer
authors.initials: T
authors.lastname: Uyar
authors.forename: Suna
authors.initials: S
authors.lastname: Timur
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Yagci
mesh_terms: D001628:Beverages / Q000032:analysis; D015374:Biosensing Techniques / Q000379:methods*; D002021:Buffers; D002851:Chromatography, High Pressure Liquid; D004563:Electrochemistry; D004566:Electrodes; D005947:Glucose / Q000032:analysis / Q000737:chemistry; D005949:Glucose Oxidase / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D053761:Nanocomposites / Q000737:chemistry*; D010084:Oxidation-Reduction; D011092:Polyethylene Glycols / Q000737:chemistry*; D019346:Sodium Acetate / Q000737:chemistry
chemical_list: D002021:Buffers; D011092:Polyethylene Glycols; D019346:Sodium Acetate; D006046:Gold; D005949:Glucose Oxidase; D005947:Glucose