Fruit-FIT: Drone Interfaced Multiplexed Sensor Suite to Determine the Fruit Ripeness

This work presents a hybrid sensor suite comprising a microneedle-based multiplexed hormone sensor and a volatile organic compound sensor integrated on a single chip. The microneedle sensors measured two phytohormones, salicylic acid and indole-3-acetic acid levels with onboard pH correction, and the volatile organic compound sensor measured the gaseous hormone ethylene. The sensor suite was deployed through a drone on ripe and unripe bell peppers before harvest. Dynamic measurement of salicylic acid, indole-3-acetic acid, and ethylene gas in bell peppers informed the progression of ripening, which will be pivotal in determining the optimum time to harvest and reducing postharvest losses.