Ultrasensitive carbon dot nanofluorescent probe for rapid imaging of ethylene dynamic changes in plants under abiotic stress exploiting aggregation-induced emission enhancement

Developing sensitive and reliable methods for the rapid, in situ detection of trace ethylene signals released by plants under abiotic stress is crucial for deciphering their complex stress-regulatory networks. However, this has remained a persistent bottleneck in plant stress physiology due to ethylene’s extremely low physiological concentrations, high spatiotemporal heterogeneity, and the lack of ultrasensitive detection tools. Herein, we report an intelligent “turn-on” fluorescent carbon dot (CD) nanoprobe (NE-CDs) constructed from 1-vinylnaphthalene and a Grubbs catalyst precursor. Through an aggregation-induced emission enhancement (AIEE) mechanism triggered by specific ethylene recognition, the NE-CDs achieve an ultrasensitive response to ethylene with a limit of detection (LOD) as low as 0.036 ppm. This represents an order-of-magnitude improvement in sensitivity compared to existing nanoprobes, enabling the precise capture of previously undetectable early or faint fluctuations in ethylene signals. Importantly, the NE-CDs were successfully applied for rapid detection, dynamic imaging and monitoring of endogenous ethylene release patterns in Arabidopsis thaliana leaves under salt and drought stress. This work not only provides a novel nanoprobe with superior performance for trace ethylene detection but, more significantly, paves a new avenue for the rapid analysis of the spatiotemporal dynamics of ethylene signaling under complex abiotic stresses and its precise regulatory mechanisms in stress adaptation. It demonstrates immense potential for advancing research into plant stress resistance mechanisms, guiding crop breeding for stress tolerance, and developing precision agriculture technologies.