Here we describe a new instrument (SpiderMass) designed for in vivo and real-time analysis. In this instrument ion production is performed remotely from the MS instrument and the generated ions are transported in real-time to the MS analyzer. Ion production is promoted by Resonant Infrared Laser Ablation (RIR-LA) based on the highly effective excitation of O-H bonds in water molecules naturally present in most biological samples. The retrieved molecular patterns are specific to the cell phenotypes and benign versus cancer regions of patient biopsies can be easily differentiated. We also demonstrate by analysis of human skin that SpiderMass can be used under in vivo conditions with minimal damage and pain. Furthermore SpiderMass can also be used for real-time drug metabolism and pharmacokinetic (DMPK) analysis or food safety topics. SpiderMass is thus the first MS based system designed for in vivo real-time analysis under minimally invasive conditions.

The formation and dynamics of a laser-produced aluminum plasma have been experimentally and theoretically investigated. The visible-emitting regions of the plasma form two structures with different lifetimes and expansion velocities. The first part of the transient ionic signal simultaneously recorded by a Langmuir probe presents an oscillatory structure. A hydrodynamic model in a nondifferentiable space-time has been established. The numerical simulation of the plasma expansion showed the plasma plume separation into two patterns. Moreover, the self-structuring of the interface appears through a negative differential conductance and the current oscillations are explained as being induced by thermal fluctuations that appear in the plasma cooling processes.