In an effort to augment the atomic emission spectra of conventional laser-induced breakdown spectroscopy (LIBS) and to provide an increase in selectivity, mid-wave to long-wave infrared (IR), LIBS studies were performed on several organic pharmaceuticals. Laser-induced breakdown spectroscopy signature molecular emissions of target organic compounds are observed for the first time in the IR fingerprint spectral region between 4-12 μm. The IR emission spectra of select organic pharmaceuticals closely correlate with their respective standard Fourier transform infrared spectra. Intact and/or fragment sample molecular species evidently survive the LIBS event. The combination of atomic emission signatures derived from conventional ultraviolet-visible-near-infrared LIBS with fingerprints of intact molecular entities determined from IR LIBS promises to be a powerful tool for chemical detection.
Vol. 9, Iss. 4 Virtual Journal for Biomedical Optics
Clayton S.-C. Yang, Ei E. Brown, Eric Kumi-Barimah, Uwe H. Hommerich, Feng Jin, Sudhir B. Trivedi, Alan C. Samuels, and A. Peter Snyder, "Mid-Infrared, Long Wave Infrared (4-12 μm) Molecular Emission Signatures from Pharmaceuticals Using Laser-Induced Breakdown Spectroscopy (LIBS)," Appl. Spectrosc. 68, 226-231 (2014)