ESPCI web site
SMBP has developed a biological mass spectrometry platform at ESPCI since the end of the 1990s, integrated in 2002 into the national platform of Montagne Saint Geneviève, future Proteomics@PSL Paris, in partnership with the Institut Curie site to support research projects for over 20 years. New analytical strategies and protocols are developed in response to the complex questions emerging from the scientific communities. When disruptive technologies are developed, we have to evolve our scientific and technical know-how to stay at the forefront of science. In 2004, we became the first French academic site equipped with an FT MS (Fourier transform mass spectrometry) for proteomics. In 2024, after implementing microfluidic solutions, Proteomics@PSL is the first platform in France to be equipped with Astral technology, combining high-resolution FT MS and high acquisition frequency TOF MS (time-of-flight mass spectrometry).
Our group is one of the few in France to work still using both MALDI and ESI sample ionization modes. Our recent results have again demonstrated the strong complementarity of these techniques, for example for the study of glycosylated polypeptides. Very promising data have been obtained using MALDI for molecular imaging. In addition, the extra dimension of ion mobility is an effective strategy to deepen our analysis, search for specific signals of minute traces in complex or degraded samples, or differentiate metal complexes after spontaneous exchanges with environmental metal ions. Several analytical strategies have been developed on model samples, from miniaturized sample processing to bioinformatics data processing. Numerous applications in archaeology have emerged, broadening our field of application to polysaccharides.
A final key point of our group, which has been an underlying theme since the 2000s, is the need to combine high specificity with high sensitivity. Thanks to our nanochromatography expertise and within the Labex IPGG framework for microfluidics, we have logically developed miniaturized tools to minimize sample loss, such as the ChipFilter. The relative amount of sample lost by non-specific adsorption increases with decreasing sample size for a constant contact surface and becomes a major obstacle. We have also worked on specific surface treatments to minimize this phenomenon. As we recently published, miniaturization is a key, even if we do not consider single-cell analysis as fully compatible with classical proteomics strategies, as opposed to the current trend. Indeed, as mass spectrometry is currently the reference and requires a statistical population (>1E3 molecules) to be informative, single-cell proteomics by mass spectrometry will never be suitable for the study of low-abundance proteins expressed at less than a few hundred copies per cell. Alternative detection methods are absolutely necessary to reach this Holy Grail.