Visible laser desorption/ionization mass spectrometry using gold nanorods

In this report, we demonstrate the novel application of gold nanorods in the laser desorption/ionization mass spectrometry. The gold nanorod substrate was fabricated by electrodepositing the gold into the pores of the porous alumina template. The embedded nanorods with diameter of similar to 15 nm were exposed to the surface by partial removal of the alumina template. The vertically aligned gold nanorods were irradiated by a frequency-doubled/-tripled Nd:YAG laser and the desorption/ionization was found to be favored by the use of 532 nm visible laser, which is in the range of the localized surface plasmon resonance. The present technique offers a potential analytical method for the low-molecular-weight analytes which are rather difficult to handle in organic matrix-assisted laser desorption/ionization mass spectrometry.