Bio-directed synthesis of platinum nanoparticles by Nymphaea alba extract: fabrication of a novel non-enzymatic hydrogen peroxide sensor

摘要

In this work, the extract of Nymphaea alba flowers was used as a reducing agent to synthesize platinum nanoparticles (Pt NPs), being such NPs characterized by different methods such as XRD, SEM and FT-IR. Crystal size of prepared Pt NPs was determined by SEM round circa 35 nm. Such characterized NPs were then applied to modify carbon paste electrodes (CPE/Pt NPs), which were electro-chemically investigated by cyclic voltammetric method. The active surface area of CPE/Pt NPs was calculated about 0.027 cm~2. Finally, the ability of this modified electrode was assessed to determine of hydrogen peroxide by amperometric technique. This modified electrode has shown a linear dynamic range of 1.5-250 μmol L~(-1) with detection limit of 0.7 μmol L~(-1). In addition, the electron transfer coefficient for hydrogen peroxide at the surface of CPE/Pt NPs was found to be 0.74. The simple preparation method, low costs (free enzyme), good stability, and efficient response are the advantages of this novel modified electrode as a sensor for determination of hydrogen peroxide.