Laser ablation sampling of materials directly into the formed liquid microjunction of a continuous flow surface sampling probe/electrospray ionization emitter for mass spectral analysis and imaging

Transmission geometry laser ablation directly into a formed liquid microjunction of a continuous flow liquid microjunction surface sampling probe/electrospray ionization emitter was utilized for molecular and elemental detection and mass spectrometry imaging. The ability to efficiently capture and ionize ablated material was demonstrated by the detection of various small soluble n-mers of polyaniline and silver ion solvent clusters formed from laser ablation of electropolymerized polyaniline and silver thin films, respectively. In addition, analysis of surfaces that contain soluble components was accomplished by coating or laminating the sample with an insoluble film to enable liquid junction formation without directly extracting material from the surface. The ability to perform mass spectrometry imaging at a spatial resolution of about 50 μm was illustrated by using laminated inked patterns on a microscope slide. In general, these data demonstrate at least an order of magnitude signal enhancement compared to the noncontact, laser ablation droplet capture-based surface sampling/ionization approaches that have been previously presented.