Application on Gold Nanoparticles-Dotted 4-Nitrophenylazo Graphene in a Label-Free Impedimetric Deoxynivalenol Immunosensor

Abstract

In this paper, we report a new concept to construct a label-free electrochemical inhibition-based immunosensor for the detection of the mycotoxin deoxynivalenol (DON) in cereal samples. The electrochemical impedance spectroscopy of tris(bipyridine) ruthenium (II) chloride was used as a marker enhanced with gold nanoparticles-dotted 4-nitrophenylazo functionalized graphene (AuNp/G/PhNO2) nanocatalyst mediated in Nafion on a glassy carbon electrode. Under the optimized conditions, the formation of immunocomplexes inhibited electron flow and increased the charge transfer resistance of the sensing interface linearly. The change in impedance was proportional to DON concentrations in the range of 6–30 ng/mL with a sensitivity and detection limit of 32.14 ΩL/ng and 0.3 μg/mL, respectively, which compares favorably with the ELISA result. The proposed sensor had a stability of 80.3%, good precision and selectivity in DON standard solution containing different interfering agents, indicating promising application prospect for this strategy in designing impedimetric, electrochemiluminescent, voltammetric or amperometric sensors.

An Electrochemical Immunosensor for Rapid and Sensitive Detection of Mycotoxins Fumonisin B1 and Deoxynivalenol

“…With the target mycotoxin-specific Ab attached on the working surface of SPE, a blank sample is tested and the DPV peak current is recorded as the signal baseline. When samples containing mycotoxins are tested, after 40 min of incubation, the Ab-toxin interaction at the electrode surface results in reduced electrochemical current due to the insulating property of the Ab-toxin complex [39]. The decrease in DPV current is proportional to the Ab vs. target toxin concentration of the tested sample.…”

Distance Effects of Phenylpiperazine-Containing Methacrylic Polymers on Optical and Structural Properties

“…The irreversible cathodic peak, common to all the OK compounds, can be assigned to 4-nitrophenyl reduction, in agreement with literature. 33 …”

Mycotoxin Determination in Foods Using Advanced Sensors Based on Antibodies or Aptamers

“…Some reports focused on the electrochemical immunosensor for DON sensing [ 93 ]. Based on the use of immunomagnetic beads (IMBs) coupled with recombinant anti-DON Fab fragment, Romanazzo [ 94 ] developed an enzyme-linked-immunomagnetic-electrochemical (ELIME) method for DON detection in cereal and cereal-based food samples.…”