# Detecting carbon dioxide concentration using mosquito neurons

At the Mauna Loa Observatory the concentration of atmospheric carbon dioxide is measured using the absorption of infra-red light. This is a statistical technique that requires constant careful calibration. Mosquitoes, drosophila, and other insects have specific cpA neurons that detect $$\ce{CO2}$$. These insects are orders of magnitude smaller and more portable than the equipment at Mauna Loa.

What work is being done on unraveling the chemical processes used by cpA neurons in order to create more accurate detection of $$\ce{CO2}$$ levels?

There are currently available electronic gas sensors that are of the same order of size as mosquito neurons, and are much easier to interface to devices and to maintain. For example, see the list of $$\ce{CO2}$$ sensors from DigiKey.
Mosquitoes do have an advantage in their ability to locate a source of $$\ce{CO2}$$, though they also rely on water vapor, heat and volatile organic chemicals to find prey. So, if you itch to try out interfacing with mosquito neurons, you might make a better directional tracker for sources of $$\ce{CO2}$$... or $$\ce{NH3}$$, $$\ce{CH3COOH}$$, etc. However, the Mauna Loa $$\ce{CO2}$$ measurements are to detect long-term changes in global $$\ce{CO2}$$, not to track down breathing prey. Mosquitoes, and their neurons, are a bit ephemeral for that.