Infrared laser ablation sample transfer for on‐line liquid chromatography electrospray ionization mass spectrometry

We have demonstrated an on‐line laser ablation sampling system and coupling of the system to liquid chromatography (LC) using an infrared (IR) laser to ablate and transfer materials into a flowing solvent stream. With this approach, samples are deposited on a microscope slide mounted on a translation stage and ablated in transmission geometry using a pulsed mid‐IR laser. The ablated material is captured in an exposed flowing solvent stream that carries the ablated material to the electrospray source. Post‐ablation separation is accomplished using a capillary column downstream of the capture zone. The performance of the system was assessed using peptide and protein mixtures ablated from the target and analyzed with and without LC separation. Copyright © 2012 John Wiley & Sons, Ltd.