An alternative to stationary, ground-mounted instrumentation for tracking air pollution trends has taken flight. Atmospheric air pollutant concentrations can now be detected in mid-air with a lab-on-a-drone system engineered by researchers in Brazil.

The quadcopter drone was designed to sample and analyze hydrogen sulfide gas while aloft and report the results in real time, negating the time-consuming need to return samples to Earth for subsequent laboratory analysis. The commercially available drone is equipped with 3D-printed analytical tools in which a green-glowing dye known as fluorescein mercuric acetate glows less brightly when exposed to the gas. An integrated blue LED boosts that reaction, allowing an onboard light sensor to precisely measure the decrease in fluorescence intensity. The greater the decrease, the greater the concentration of hydrogen sulfide gas in the area.

[See also: Drones drop in to survey nuclear decommissioning site]

The system was tested at a wastewater treatment plant where it sampled ground-level air as well as at around 30 ft and 65 ft altitude at three different times throughout the day. Real-time monitoring was enabled by transmitting analytical data via Bluetooth to a smartphone. The airborne laboratory documented a pollutant range of 15 ppb to 200 ppb and an increase in hydrogen sulfide concentration in the evening.

According to researchers from Federal University of Uberlandia and Universidade Federal de Goiás, the Arduino-controlled drone described in the journal Analytical Chemistry could be adapted to detect other pollutants of interest.

To contact the author of this article, email shimmelstein@globalspec.com