Assessment of Salt Stress to Arabidopsis Based on the Detection of Hydrogen Peroxide Released by Leaves Using an Electrochemical Sensor.

Salt stress will have a serious inhibitory effect on various metabolic processes of plant cells, this will lead to the excessive accumulation of reactive oxygen species (ROS). Hydrogen peroxide (H 2 O 2 ) is a type of ROS that can severely damage plant cells in large amounts. Existing methods for assessing the content of H 2 O 2 released from leaves under salt stress will cause irreversible damage to plant leaves and are unable to detect H 2 O 2 production in real time. In this study, on the strength of a series of physiological indicators to verify the occurrence of salt stress, an electrochemical sensor for the detection of H 2 O 2 released from leaves under salt stress was constructed. The sensor was prepared by using multi-walled carbon nanotube-titanium carbide-palladium (MWCNT-Ti 3 C 2 T x -Pd) nanocomposite as substrate material and showed a linear response to H 2 O 2 detection in the range 0.05-18 mM with a detection limit of 3.83 μM. Moreover, we measured the determination of H 2 O 2 released from Arabidopsis leaves at different times of salt stress by the sensor, which was consistent with conventional method. This study demonstrates that electrochemical sensing is a desirable technology for the dynamic determination of H 2 O 2 released by leaves and the assessment of salt stress to plants.