Imaging-imaging analysis of trace-elements and nanoparticles using laser ablation-ICP-mass spectrometry

In the laser ablation-ICP-MS (LA-ICP-MS) method, samples are analyzed at atmospheric pressure, so sample replacement is easy. In addition, by narrowing down the laser irradiation diameter, it is possible to analyze the chemical composition and isotope composition of the specified part of a solid sample, so it is attracting attention as an elemental imaging analysis method. By utilizing the high quantitative performance, analytical sensitivity, and spatial resolution of the LA-ICP-MS method, the imaging analysis of trace elements is rapidly spreading. Recently, the trials of biomolecular imaging have been conducted by applying the LA-ICPMS method and immune reaction. In LA, a sample is vaporized and aerosolized using a pulsed laser, and the vapor and vapor-aerosol generated from a small area of laser irradiation point appear with a temporal expanse at a stage when introduced into ICP. The vapor and vapor-aerosol introduced into ICP are ionized in about 10 ms, and successively, electrically accelerated in a mass spectrometer. There, they are mass-separated and detected at a speed more than 100 times the speed of sound. (A.O.)