Development of Sample Deposition Methods for Laser-Induced Acoustic Desorption (LIAD) Coupled with Molecular Rotational Resonance (MRR) Spectroscopy

Laser-induced acoustic desorption (LIAD) is an evaporation technique that allows for thermally labile, nonvolatile neutral compounds to be vaporized without the need for derivatization or excessive heating. After a thin coating of a sample is applied to a titanium foil, the opposite side of the foil is subjected to laser irradiation to desorb neutral compounds from the opposite side into the gas phase. LIAD shows great potential for facilitating the analysis of a wide variety of compounds when coupled with molecular rotational resonance (MRR) spectroscopy. In this work, a few model compounds were chosen based on previous research to optimize the sample preparation and foil deposition methods for LIAD/MRR spectroscopy. One possible strategy to maximize the MRR signal is attempting to generate amorphous samples on the foils instead of ordered, crystalline samples. Changing the solvents used for dissolution of the compounds and freeze-drying the sample before deposition were also investigated.