Continuous-wave laser ablation enables high-resolution ambient mass spectrometry imaging
Year: 2026
Type: preprint
Abstract: Continuous-wave lasers are generally not considered for applications demanding precision ablation, because sustained heating in bulk tissue causes extensive thermal damage. Here we show that this limitation does not apply to thin sections: a 2.91 µm continuous-wave laser leaves no resolvable heat-affected zone beyond the ablation track on 10 µm thick cryosections, a confinement consistent with heat sinking vertically into the glass slide rather than diffusing laterally. This defines a distinct sampling regime in which confined material removal by a continuous-wave mid-infrared laser preserves the sample morphology for post-hoc staining and optical imaging while generating a laminar plume well suited for aspiration into the atmospheric inlet of a mass spectrometer. Here we demonstrate matrix-free ambient mass spectrometry imaging at 3 µm pixel size with a fibre-delivered beam, uniting few micron scale sampling, broad chemical coverage, and same-section co-registration on a readily adoptable platform assembled entirely from commercial components.
Source: ChemRxiv
Language: English
Subfield: Spectroscopy
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7220857761