New laboratory method reduces costs for reliable, continuous measurements of CO2 evolution and "Offers the possibility for nearly all biological and chemical laboratories to adapt to this technology"
Researchers in Mexico have developed a low-cost method for continuously measuring carbon dioxide emitted during microbial respiration.
This makes it much easier to reliably determine soil fertility or contamination.
The measurement software they have chosen for their system is Windmill, which they downloaded for free.
CO2 is often used as an indicator for microbiological activity in soils or sediments.
Inhibition of microbial respiration indicates a contaminated soil.
In agricultural science, the amount of CO2 efflux of soils is an indication of soil fertility.
CO2 respiration measurements are also used to evaluate microbiological remediation processes, predicting or optimising microbial processes in contaminated soils.
Previously, continuously monitoring CO2 emission was expensive.
It needed a strict flow control, repeated calibration, air filtering and continuous correction for temperature and atmospheric pressure.
In the new system evolved CO2 is absorbed and precipitated as carbonate, which causes a decrease in ionic strength and conductivity of solution.
This decrease in ionic strength is continuously detected by a conductivity meter connected to a PC.
The free Windmill data acquisition software runs under Windows on the PC and regularly reads the conductivity and temperature of solution from the meter.
It then automatically transfers the data to Microsoft Excel software, which corrects the conductivity readings for temperature and calculates the CO2 concentration.
This new laboratory method reduces costs for reliable, continuous measurements of CO2 evolution and, according to the researchers, "Offers the possibility for nearly all biological and chemical laboratories to adapt to this technology".
