The design and application of an inkjet-printed electrochemically reduced graphene oxide microelectrode for HT-2 mycotoxin immunoenzymatic biosensing is reported. A water-based graphene oxide ink was first formulated and single-drop line working microelectrodes were inkjet-printed onto poly(ethylene 2,6-naphthalate) substrates, with dimensions of 78 μm in width and 30 nm in height after solvent evaporation. The printed graphene oxide microelectrodes were electrochemically reduced and characterized by Raman and X-ray photoelectron spectroscopies in addition to microscopies. Through optimization of the electrochemical reduction parameters, differential pulse voltammetry were performed to examine the sensing of 1-naphthol (1-N), where it was revealed that reduction times had significant effects on electrode performance. The developed microelectrodes were then used as an immunoenzymatic biosensor for the detection of HT-2 mycotoxin based on carbodiimide linking of the microelectrode surface and HT-2 toxin antigen binding fragment of antibody (anti-HT2 (10) Fab). The HT-2 toxin and anti-HT2 (10) Fab reaction was reported by anti-HT2 immune complex single-chain variable fragment of antibody fused with alkaline phosphatase (anti-IC-HT2 scFv-ALP) which is able to produce an electroactive reporter - 1-N. The biosensor showed detection limit of 1.6 ng ∙ mL-1 and a linear dynamic range of 6.3 - 100.0 ng ∙ mL-1 within a 5 min incubation with 1-naphthyl phosphate (1-NP) substrate.
- MeSH
- Biosensing Techniques instrumentation MeSH
- Equipment Design MeSH
- Electrochemical Techniques instrumentation MeSH
- Graphite chemistry MeSH
- Antibodies, Immobilized chemistry MeSH
- Immunoenzyme Techniques instrumentation MeSH
- Microelectrodes MeSH
- Oxidation-Reduction MeSH
- Reagent Strips analysis MeSH
- T-2 Toxin analogs & derivatives analysis MeSH
- Publication type
- Journal Article MeSH