Cold-spray ionization (CSI) is a variant of electrospray ionization wherein the nebulizing gas is cooled to -40 °C with liquid nitrogen . CSI-MS allows to characterize labile non-covalent complexes unobservable by ESI, to detect reaction intermediates, to uncover the solvated structure of organometallics compounds, or to understand the organization of deep eutectic solvents . Recently, the softness of CSI compared to ESI was evaluated quantitatively on an AccuTOF CS mass spectrometer equipped with a dual ESI/CSI source .