A gold nanoparticle-boosted disposable paper-based electrochemiluminescence biosensor for in situ detection of H2O2 in tomato leaves.

This work presents a gold nanoparticle (Au NP)-boosted disposable paper-based electrochemiluminescence (ECL) biosensor for minimally invasive on-leaf in situ detection of endogenous H2O2 in tomato leaves. The inherent capillary action of filter paper (FP) was employed to simplify reagent delivery, while gold nanoparticles (Au NPs) catalytically activated H2O2 to generate reactive oxygen species, thereby driving the ECL signal output. This simple, low-cost paper-based platform enabled time-resolved monitoring of H2O2 in stressed plants, providing a reliable in situ strategy for evaluating tomato physiology and early disease/pest warning.