Fourier transform infrared photoacoustic spectroscopy (FT-IR-PAS) has been applied to the problem of identifying pollen samples. One hundred measurements were made on a set of pollen samples comprising five families and ten species. Chemometric analysis of the resulting spectra showed evidence of clustering. Construction of a spectral library allowed pollens in the set to be correctly identified as the first match on the basis of photoacoustic spectra at the species (99%) or family (100%) level.
George Parodi, Pearl Dickerson, and Jacqueline Cloud, "Pollen Identification by Fourier Transform Infrared Photoacoustic Spectroscopy," Appl. Spectrosc. 67, 342-348 (2013)