In situ synthesis of biomolecule encapsulated gold-cross-linked poly(ethylene glycol) nanocomposite as biosensing platform: A model study

WOS: 000281326600009
PubMed ID: 20605749
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. (C) 2010 Elsevier B.V. All rights reserved.
Istanbul Technical University (ITU)Istanbul Technical University; Ege UniversityEge University; TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK); UNAM-Institute of Materials Science and Nanotechnology through the National Nanotechnology Research CenterIhsan Dogramaci Bilkent University
This work was supported by Istanbul Technical University (ITU) and the Ege University Research Grants. M. U. Kahveci thanks to TUBITAK for financial support as a graduate scholarship. Prof. N. Ertas is acknowledged for the fruitful discussions on the electrochemical data. The State Planning Organization of Turkey (DPT) is acknowledged for the support of UNAM-Institute of Materials Science and Nanotechnology through the National Nanotechnology Research Center Project. H. Deniz and M. Guler are also acknowledged for helping TEM imaging and sample preparation for TEM, respectively.