Rapid and visual detection and quantification of ethylene released from ripening fruits: the new use of Grubbs catalyst.

Herein we report on fluorophore-tagged Grubbs catalysts as turn-on fluorescent probes for the sensitive detection and quantitation of ethylene, a plant hormone that plays a critical role in many phases of plant growth and fruit ripening. The ruthenium (Ru) based weakly fluorescent probes were prepared handily through metathesis reaction between the first generation Grubbs catalyst and selected fluorophores that have high quantum yields and contain terminal vinyl groups. Upon exposure to ethylene, fluorescence enhancement was observed via the release of fluorophore from the probe. Our probe shows an excellent limit of detection (LOD) for eth-ylene at 0.9 ppm in air and was successfully applied for monitoring ethylene released during the fruit ripening process. Our work opens up a new avenue of application of Grubbs catalysts for bioanalytical chemistry of ethylene, which is critically important in plant biology, agricul-ture and food industry.