S.N. Jackson, S.M. Dutta, K.K. Murray, “A nitrocellulose matrix for infrared matrix-assisted laser desorption/ionization of polycyclic aromatic hydrocarbons,” Rapid Commun. Mass Spectrom.18 (2004) 228–230. doi:10.1002/rcm.1296.


IR-MALDI mass spectra of benzo[a]pyrene with a nitrocellulose matrix
IR-MALDI mass spectra of benzo[a]pyrene with a nitrocellulose matrix at the indicated wavelengths between 2.45 and 3.85 mm. The spectra are an average of five laser shots and are plotted on the same scale.

Infrared matrix-assisted laser desorption/ionization (IR-MALDI) of low molecular weight polycylic aromatic hydrocarbons (PAHs) was performed using a 3 µm mid-infrared laser and nitrocellulose as the matrix.  No other liquid or solid matrix material was added. Positive ion mass spectra obtained with the nitrocellulose matrix contain an intense molecular ion peak with no interference from matrix or alkali cations. PAH mass spectra were obtained at wavelengths between 2.44 to 3.88 mm with the best performance between 2.5 and 3.0 µm and near 3.6 µm. The relative intensities of the analyte signal at the different wavelengths is consistent with absorption of the IR radiation by the nitrocellulose with a possible additional contribution due to the absorption of residual water or solvent.