New Approach in Calibration of Passive Permeation Samplers used for Sampling of VOCs from Air
Passive sampling is a very attractive alternative to active sampling due to its simplicity and low cost. Among the passive samplers used in air analysis, permeation passive samplers offer unique advantages, including elimination of problems related to moisture, low sensitivity to air currents and to temperature changes. The biggest drawback of permeation passive samplers is the need to calibrate them experimentally for each individual target analyte. This limited the applicability of permeation passive samplers exclusively to target compound analysis. The approach proposed to estimate the values of the calibration constants based on physico-chemical properties of the analytes and/or their retention parameters eliminate this fundamental limitation of permeation passive sampling.
The approach proposed to estimate the values of the calibration constants based on physico-chemical properties of the analytes (carbon atoms among families of compounds, the molecular weights of the compounds, their boiling points) and/or their retention parameters eliminate this fundamental limitation of permeation passive sampling. The PDMS membrane used in permeation passive sampler assured high sampling rates of analytes. This makes it possible to deploy permeation passive samplers in the same way in which active sampling is deployed. The samplers can be exposed to an unknown sample without the need to calibrate their response towards all analytes.