The Application of Ordered Mesoporous Carbon and Glod Nanoparticles Composite in Bioensor
|School||Northeast Normal University|
|Keywords||Biosensor Gold nanoparticles Ordered mesoporous carbon Hydrogen peroxide Glucose oxidase|
In recent years, gold nanoparticles （GNPs） are most extensively studied because of their unique size dependent electronic properties and excellent biocompatibility, which were mainly applied to electrocatalysis and biosensor. Ordered mesoporous carbon （OMC） has been gained much attention in the fields of electrochemsitry and sensors, owing to its considerable properties, such as high specific surface area, ordered tunable pore, and chemical inertness etc. In order to take full advantage the merits of GNPs and OMC, we firstly synthesized the nanocompisite of GNPs-OMC using different methods. This dissertation mainly consists of the following two aspects:1. A facile and controllable electrodeposition method was developed to directly attach gold nanoparticles （GNPs） on ordered mesoporous carbon （OMC）. The GNPs on OMC substrate were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and X-ray photoelectron spectrometer （XPS）, respectively. A non-enzymatic hydrogen peroxide （H2O2） sensor was fabricated on GNPs-OMC/GCE. The sensor demonstrated a fast amperometric response （2.5s）, a wide linear range toward H2O2 concentrations between 2.0×10-6 and 3.92×10-3 M （R=0.999）, and a low detection limit of 0.49μM （S/N=3）. Moreover, it exhibited good reproducibility and long-term stability. The excellent electrocatalytical activity might be attributed to the synergistic effect of OMC and GNPs.2. Ordered mesoporous carbon-Au nanoparticles （OMC-Au） nanocomposites were synthesized by a one-step chemical reduction route. Due to the large surface area and high conductivity of OMC, good biocompatibility of OMC and Au nanoparticles, a mediator-free glucose biosensor was fabricated by immobilizing glucose oxidase （GOD） on the OMC-Au nanocomposite modified glassy carbon （GC） electrode. Direct electron transfer between GOD and the electrode was achieved and the electron transfer rate constant （ks） was calculated to be 5.03 s-1. The Michaelis–Menten constant value of GOD immobilized on the OMC-Au/GC electrode surface was found to be 0.6 mM. The glucose biosensor exhibits a linear range from 0.05 to 20.0mM. This biosensor also shows good reproducibility, excellent stability and the negligible interferences from ascorbic acid and uric acid.