EPJ Plus Highlight - New instrument probes how complex molecules form on cosmic dust

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Published on 29 May 2026

Researchers have designed a non-destructive mass spectrometer that traps and measures individual nanoparticles, which could contribute to our understanding of how complex organic molecules form in interstellar space

Throughout interstellar space, molecules attached to the surfaces of dust grains are constantly being transformed through a combination of chemical reactions and physical forces. How these physicochemical processes play out is strongly tied to the sizes of dust grains – underpinning the formation of complex organic molecules. To study these processes, experiments so far have reproduced them on thick multilayer ice layers, but these surfaces can't fully capture the intrinsic properties of cosmic dust grains.

Through new research published in EPJ Plus, Stefano Bovino and colleagues at the University of Concepción, Chile, introduce a more advanced experimental approach, involving a non-destructive mass spectrometer for charged nanoparticles. Their setup could help researchers to deepen their understanding of how complex molecules can form in the harsh environment of outer space.

In 2001, research led by Stephan Schlemmer and Dieter Gerlich at the University of Technology Chemnitz, Germany, introduced a non-destructive form of mass spectrometry, involving suspending the particle in an ion trap. Here, the particle oscillates physically at specific frequencies which depend on its mass-to-charge ratio – so by illuminating the particle with a laser, researchers can track how the intensity of the scattered light fluctuates. From this, they can precisely reconstruct the particle's mass.

In their study, Bovino's team expanded on Schlemmer and Gerlich’s design: equipping the setup with a triboelectric injection system, which charges nanoparticles through contact; and a split ring electrode ion trap which allows the confined nanoparticle to be probed more easily. They also applied a charge-stepping procedure where the nanoparticle is gently bombarded with electrons. When a single electron collides with the particle, it creates a discrete jump in charge – altering the frequency of the particle's oscillations. By measuring these shifts, the particle's mass can be calculated with high precision.

Having demonstrated this setup, the researchers are confident that its working principles will enable measurements of several key physicochemical properties. These would include the binding energies of molecules on cosmic dust grains, alongside studies of ice formation and complex chemical reactions: ultimately unveiling the size dependence of these fundamental processes.