Chemists have created a tiny sensor able to detect ethylene gas (a plant hormone) in minuscule concentrations. It could be used to monitor produce ripeness and prevent food spoilage. U.S. supermarkets may be losing about 12% of their fruits and vegetables to spoilage every year so this could be very helpful. Having never taken chemistry, I don’t understand how it works, but others might.
https://www.sciencedaily.com/releases/2020/03/200318143641.htm