A spatially programmable microfluidic chip for multi-stage particle and cell separation - EurekAlert!

We’re sharing this article early to provide faster access to peer-reviewed, accepted research. It is citable and carries a permanent DOI. This version is subject to further edits and will be replaced automatically by the final Version of Record. All legal disclaimers apply. AbstractMany biologically important molecules are structural isomers that share the same molecular mass yet differ in shape, bonding and function. This creates an ambiguity for mass spectrometry imaging (MSI), where chemically distinct species can be indistinguishable on the mass-to-charge (m/z) scale and therefore cannot be reliably mapped in heterogeneous materials. Here we demonstrate that Orbitrap secondary ion mass spectrometry (OrbiSIMS) can provide an orthogonal contrast that enables both identification and spatial separation of isomeric molecules directly on surfaces. By exploiting structure-dependent secondary-ion dissociation and gas-phase collisional effects during ion transmission, we discriminate isomeric trisaccharides raffinose, maltotriose and melezitose and spatially resolve raffinose and maltotriose in mixtures.

A particle does not have to pass through a magnetic field to be influenced by it. That surprising feature of quantum physics has now been recreated by researchers at the University of Oxford, who used a hybrid quantum computer to demonstrate how an invisible magnetic influence can bring a simulated particle's movement to a complete stop. The experiment reproduced a phenomenon known as the Aharonov-Bohm effect, in which a charged particle traveling around a region containing magnetic flux experiences a measurable change in its quantum state, even though its path never takes it through the magnetic field itself.