Characterizing the small-molecule corona of nanoparticles by capillary electrophoresis-mass spectrometry: a new approach in nanoscience

Rawi Ramautar, Biomedical Microscale Analytics, Leiden University, Leiden, The Netherlands (r.ramautar@lacdr.leidenuniv.nl)

The use of nanomaterials in biomedical and biotechnological applications is growing, and such materials are also released into the environment as consumer products. Due to their high surface free energy, nanomaterials adsorb biomolecules on contact with biological samples. In particular, proteins bind to the surface of nanoparticles to form a coating around the nanoparticle, known as protein corona. The small-molecule or metabolite corona is a much overlooked aspect of the nanoparticle corona. The corona affects the biological identity of the nanoparticle and may thus affect biomedical applications or modulate nanotoxicological effects. Therefore, in the development of nanomaterials for any kind of biological or biomedical applications, it is essential to understand the formation and evolution of the corona.

In this work, we show that capillary electrophoresis-electrospray ionization mass spectrometry (CE-MS) using a low-flow interfacing technique offers an exciting platform to characterise the polar and charged compounds found within the metabolite corona. This work is the first to quantitativly assess the metabolite corona of various nanoparticles incubated in academic test solutions and human plasma. Initial findings suggest that each studied nanoparticle has a unique small-molecule fingerprint dependent upon their physico-chemical properties and that the presence of proteins has a significant impact upon the formation of the metabolite corona.

Overall, these results represent the first application of CE-MS to nanoparticle corona characterisation yielding highly sensitive and reproducible data for highly polar and charged metabolites. Thus, opening a new area of coronal analysis while simultaneously introducing CE-MS-based metabolomics to the nanosciecne community.

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Abstract Reference & Short Personal Biography of Presenting Author

Rawi Ramautar obtained his PhD on the development of capillary electrophoresis-mass spectrometry methods for metabolomics from Utrecht University, the Netherlands, in 2010. Intrigued by metabolomics for disease prediction and diagnosis, Rawi switched to the Leiden University Medical Center to broaden his horizon on this topic. In 2013 and 2017, he received the prestigious Veni and Vidi research grants from the Netherlands Organization for Scientific Research for the development of CE-MS approaches for volume-restricted metabolomics. Currently, he is a principal investigator at the Leiden University where his group is developing microscale analytical workflows for sample-restricted biomedical problems. Rawi Ramautar was recently selected for the Top 40 under 40 Power List of the Analytical Scientist.