Noninvasive in-vehicle alcohol detection with wavelength-modulated differential photothermal radiometry.

This study describes the potential of wavelength-modulated differential photothermal radiometry (WM-DPTR) for non-invasive in-vehicle alcohol detection which can be of great importance in reducing alcohol-impaired driving. Ethanol content in the range of concern, 0-100 blood alcohol concentration (BAC) in water phantoms and blood serum diffused in human skin in vitro were measured with high sensitivity. The results show that the WM-DPTR system can be optimized for alcohol detection with the combination of two sensitivity-tuning parameters, amplitude ratio R and phase shift ΔP. WM-DPTR has demonstrated the potential to be developed into a portable alcohol ignition interlock biosensor that could be fitted as a universal accessory in vehicles.