title: Disposable biosensor based on platinum nanoparticles-reduced graphene oxide-laccase biocomposite for the determination of total polyphenolic content.
abstract: A disposable amperometric biosensor was developed for the detection of total polyphenolic compounds from tea infusions. The biosensor was designed by modifying the surface of a carbon screen-printed electrode with platinum nanoparticles and reduced graphene oxide, followed by the laccase drop-casting and stabilization in neutralised 1% Nafion solution. The obtained biosensor was investigated by scanning electron microscopy and electrochemical techniques. It was observed that platinum nanoparticles-reduced graphene oxide composite had synergistic effects on the electron transfer and increased the electroactive surface area of the carbon screen-printed electrode. The constructed analytical tool showed a good linearity in the range 0.2-2 μM for caffeic acid and a limit of detection of 0.09 μM. The value of Michaelis-Menten apparent constant was calculated from the electrochemical version of Lineweaver-Burk equation to be 2.75 μM. This disposable laccase biosensor could be a valuable tool for the estimation of total polyphenolic content from tea infusions.
authors.affiliation: Centre of Bioanalysis, National Institute of Research and Development for Biological Sciences, Bucharest, Romania.
authors.forename: Sandra A V
authors.initials: SA
authors.lastname: Eremia
authors.forename: Ioana
authors.initials: I
authors.lastname: Vasilescu
authors.forename: Antonio
authors.initials: A
authors.lastname: Radoi
authors.forename: Simona-Carmen
authors.initials: SC
authors.lastname: Litescu
authors.forename: Gabriel-Lucian
authors.initials: GL
authors.lastname: Radu
mesh_terms: D001672:Biocompatible Materials; D015374:Biosensing Techniques; D006108:Graphite / Q000737:chemistry*; D042845:Laccase / Q000737:chemistry*; D053768:Metal Nanoparticles; D008855:Microscopy, Electron, Scanning; D010087:Oxides / Q000737:chemistry; D010984:Platinum / Q000737:chemistry*; D059808:Polyphenols / Q000032:analysis*; D015203:Reproducibility of Results
chemical_list: D001672:Biocompatible Materials; D010087:Oxides; D059808:Polyphenols; D010984:Platinum; D006108:Graphite; D042845:Laccase