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The group is developing and applying a novel, atomically precise surface preparation method, electrospray ion beam deposition (ES-IBD), which is based on the preparative use of mass spectrometry. We use this method to enable atomically resolved microscopy of individual molecules to investigate the structure and properties of complex molecular systems at the single molecular level. This encompasses synthetic as well as biological molecules. Further, we employ the specific properties of  ES-IBD to fabricate novel, covalently bonded molecular surface coatings. 

Combining native MS and cryo-EM

New preprint

In our latest preprint, Mass-selective and ice-free cryo-EM protein sample preparation via native electrospray ion-beam depositionwe introduce native electrospray ion-beam deposition (native ES-IBD), a mass-selective sample preparation workflow for cryo-EM. Folded protein ions are generated by native electrospray ionization, mass-filtered, and gently deposited on cryo-EM grids, which are subsequently frozen in liquid nitrogen. Native ES-IBD has the potential to complement and accelerate established cryo-EM sample preparation workflows, by direct correlation between cryo-EM maps with precise information on composition and conformation. We show 3D reconstructions of protein assemblies purified in the gas-phase.

"Splat chemistry"

Our most recent paper featured in Nature Reviews, New Scientist, PRL Viewpoint and Chemistry World

Our recent paper in Physical Review Letters, Fast Molecular Compression by a Hyperthermal Collision Gives Bond-Selective Mechanochemistry, has garnered interest in many review publications. 

It has been featured in Nature Reviews Chemistry , New Scientist, and Chemistry World, published by the Royal Society of Chemistry, as well as being featured in Viewpoint in Physical Review Letters. 

About the experiment: Using electrospray ion beam deposition, we collide the complex molecule Reichardt’s dye at low, hyperthermal translational energy with a copper surface and image the outcome at single-molecule level by STM. We observe bond-selective reaction induced by the translational kinetic energy. The collision impulse compresses the molecule and bends specific bonds, prompting them to react selectively. This dynamics drives the system to seek thermally inaccessible reactive pathways, since the compression timescale (subpicosecond) is much shorter than the thermalization timescale (nanosecond). The fate of the molecule depends on its orientation when hitting the surface - it can either remain intact, crack or split. This gives great insights into better understanding mechanochemistry.

Imaging single glycan molecules

Our paper in Nature

In our recent paper in Nature we were able to show direct imaging of single glycan molecules that are isolated by mass-selective, soft-landing electro spray ion beam deposition and imaged by low-temperature tunnelling microscopy. The sub-nanometre resolution of the technique enables the visualisation of glycan connectivity and discrimination between regioisomers. Direct glycan imaging is an important  step toward a better understanding of the structure of carbohydrates. 

 

The publication was featured in Nature Methods

New Paper on Ion Transport in Gas Flow in ESI heated Capillary

Transfer conditions and transmission bias in capillaries of vacuum interfaces

In detailed simulations done by our colleagues in Berlin (J. Reiss CFD group, TU-Berlin) we look at the ion transport in transfer capillaries. We illuminate how heating affects the transport and the ion distribution. Also we see how space charge favours ions of low mobility and charge states to be transmitted. The paper

Bernier et al., IJMS 447 (2020) 116239