Chemometrics approach to Cantilever enhanced photoacoustic spectroscopy with Quantum Cascade lasers

Cantilever-enhanced Photoacoustic Spectroscopy in combination with Wavelength Modulation Spectroscopy was used for the multicomponent analysis of gases. Distributed feedback Quantum Cascade Laser tunable in the region of similar to 1045 - 1048 cm(-1) was used as the excitation source. Principal component analysis (PCA) and Partial Least Squares (PLS) (the pls package in the statistical software R) methods were applied to a mixture of selected substances (methanol and ethanol) in the gas phase to both simulated (www.spectraplot.com) and experimentally acquired spectra, PCA predicting the number of substances and PLS its concentrations.