Ethylene (C2H4) functions both as a key phytohormone regulating plant growth and development and as an essential feedstock in organic chemical synthesis. Reliable detection of C2H4 is critical for monitoring emissions during crop cultivation and ensuring safety in industrial transportation. However, most existing C2H4 sensors rely on noble-metal catalysts and/or high-operating temperature, which significantly constrain their practical applications. Moreover, achieving high specificity in C2H4 recognition remains a major challenge. Inspired by the signal transduction mechanism of plant C2H4 receptor, this study propose a biomimetic sensing strategy based on a facilely synthesized cuprous-cystine complex (Cu2Cyt), which features a sulfur-bridged Cu+ coordination center that mimics the biological binding site for C2H4 recognition. The noble-metal-free wearable sensor was fabricated by depositing a Cu2Cyt/MXene composite onto a flexible interdigital electrode, enabling room-temperature detection of C2H4 emitted from fruits or leaked from transport pipelines of chemical industries. It exhibits a detection range (0.05-5 ppm), an ultra-low detection limit of 1.07 ppb, fast response/recovery (51/92 s), high sensitivity of 3.64%·ppm-1 in trace concentration range of 0-0.5 ppm, and good reversibility and reproducibility. Overall, this work offers a bioinspired design strategy for low-cost, high-performance, noble-metal-free, and wearable sensors, capable of trace-level C2H4 monitoring.
Xu et al. (2026) studied this question.