Bacterial Peroxidase on Electrochemically Reduced Graphene Oxide for Highly Sensitive H2O2 Detection

• Published in: Chembiochem : a European journal of chemical biology 2022-09, Vol.23 (17), p.n/a
• Main Authors: Bhardwaj, Sheetal K., Knaus, Tanja, Garcia, Amanda, Yan, Ning, Mutti, Francesco G.
• Format: Article
• Language: English
• Subjects: bacterial peroxidases; biocatalysis; biosensors; Chemical sensors; DyP peroxidases; Electrochemistry; Electrodes; Graphene; graphene oxide electrodes; H2O2 detection; Horseradish peroxidase; Hydrogen peroxide; Immobilization; Indium tin oxides; Peroxidase; Polyethylene; Polyethylene terephthalate; Structural integrity
• ISSN: 1439-4227; 1439-7633
• DOI: 10.1002/cbic.202200346

Peroxidase enzymes enable the construction of electrochemical sensors for highly sensitive and selective quantitative detection of various molecules, pathogens and diseases. Herein, we describe the immobilization of a peroxidase from Bacillus s. (BsDyP) on electrochemically reduced graphene oxide (ERGO) deposited on indium tin oxide (ITO) and polyethylene terephthalate (PET) layers. XRD, SEM, AFM, FT‐IR and Raman characterization of the sensor confirmed its structural integrity and a higher enzyme surface occupancy. The BsDyP‐ERGO/ITO/PET electrode performed better than other horseradish peroxidase‐based electrodes, as evinced by an improved electrochemical response in the nanomolar range (linearity 0.05–280 μM of H2O2, LOD 32 nM). The bioelectrode was mechanically robust, active in the 3.5–6 pH range and exhibited no loss of activity upon storage for 8 weeks at 4 °C. A bacterial peroxidase (BsDyP) from the “dye‐decolorizing” family was immobilized on electrochemically reduced graphene oxide (ERGO) deposited on indium tin oxide (ITO) and polyethylene terephthalate (PET) layers to create a mechanically robust biosensor with a shelf‐life of eight weeks. This biosensor was characterized for the highly selective and sensitive detection of hydrogen peroxide (linearity 0.05–280 μM, LOD 32 nM).