Evaluation of a galvo-based novel fs-LA-ICP-MS/MS platform for high-precision elemental analysis with flexible large spots

Abstract

Conventional femtosecond laser ablation (fs-LA) systems offer low thermal effects but are historically constrained by small spot sizes and depth-dependent fractionation, limiting their sensitivity for ultra-trace analysis and bulk representativeness. In this work, we evaluate a novel galvanometer-scanning fs-LA system coupled with a triple-quadrupole ICP-MS/MS to overcome these limitations. We introduced an empirical ablation efficiency factor (R) to systematically optimize complex scanning parameters—including divider, scan (Mark) speed, and jump speed, etc.—establishing three distinct ablation protocols: galvo pulse, continuous, and line scan modes. A key methodological advancement involves the synergy between unconstrained large ablation-area (up to 500 µm) and the electronic dilution capability of the ICP-MS/MS. For NIST 614, BIR-1G and iron meteorites, the combination of a larger ablation-area and the extended dynamic range of the ICP-MS enabled analytical errors for ∼10 ppb concentrations to be constrained within ±20%. This study demonstrates that the galvanometer-based fs-LA-ICP-MS/MS platform substantially expands the dynamic range of in situ analysis and, to some extent, delivers trace-element detection capability comparable to that of SF-ICP-MS, while maintaining accurate quantification of elements spanning several orders of magnitude in concentration.