Abstract
Electrochemical sensors that can determine single/multiple analytes remain a key challenge in miniaturized analytical systems and devices. In this study, we present in situ synthesis and modification of gold nanodendrite electrodes to create an electrochemical system for the analysis of hydrogen peroxide. The sensor system consisted of the reference and counter electrodes as well as the working electrode. Electrochemical reduction of graphene oxide, ErGO, on the thin-film gold and gold nanodendrite working electrodes was used to achieve an efficient sensor interface for the adsorption of a biomimetic electrocatalytic sensor material, Mn(III) meso-tetra(N-methyl-4-pyridyl) porphyrin complex, with as high as 10–10 mol cm−2 surface coverage. The sensor system demonstrated a detection limit of 0.3 µM H2O2 in the presence of oxygen. Electrochemical determination of hydrogen peroxide in plant material in the concentration range from 0.09 to 0.4 µmol (gFW)−1 using the electrochemical sensor system was shown as well as in vivo real-time monitoring of the hydrogen peroxide dynamics as a sign of abiotic stress (intense sunlight). Results of the electrochemical determination were in good agreement with the results of biochemical analysis with the spectrophotometric detection. We anticipate that this method can be extended for the synthesis and integration of multisensor arrays in analytical microsystems and devices for the quantification and real-time in vivo monitoring of other analytes and biomarkers.
Highlights
Hydrogen peroxide plays an essential role in developmental and adaptive responses in animal and plant cells (Neill et al, 2002; Quan et al, 2008; Kreslavski et al, 2012; Zandalinas and Mittler 2018; Smirnoff and Arnaud 2019)
Cyclic voltammogram of a thin-film gold electrode after adsorption of the MnTMPyP complex revealed no redox processes of the porphyrin complex, as it is exemplarily shown on Supplementary Figure S1
The electrochemical deposition of the electrochemically reduced graphene oxide (ErGO) on the carbon fiber (Bai et al, 2016) and stainless steel (Farajikhah et al, 2019) electrodes has been used to create an interface for the electrochemical sensors
Summary
Hydrogen peroxide plays an essential role in developmental and adaptive responses in animal and plant cells (Neill et al, 2002; Quan et al, 2008; Kreslavski et al, 2012; Zandalinas and Mittler 2018; Smirnoff and Arnaud 2019). In plants, it is produced by electron transport in chloroplasts and mitochondria via superoxide, peroxisomal oxidases, plasma membrane NADPH oxidase, and other oxidases and peroxidases (Quan et al, 2008; Smirnoff and Arnaud 2019). The development of methods for the quantification and real-time in vivo monitoring of hydrogen peroxide in plant tissue will enable a better understanding of its role in plant physiology, development, and adaptation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
