Electrospray sample injection for single-particle imaging with X-ray lasers

Bielecki, J.; Hantke, M. F.; Daurer, B. J.; Reddy, H. K. N.; Hasse, D.; Larsson, D. S. D.; Gunn, L. H.; Svenda, M.; Munke, A.; Sellberg, J. A.; Flueckiger, L.; Pietrini, A.; Nettelblad, C.; Lundholm, I.; Carlsson, G.; Okamoto, K.; Timneanu, N.; Westphal, D.; Kulyk, O.; Higashiura, A.; van der Schot, G.; Loh, D.; Wysong, T. E.; Bostedt, C.; Gorkhover, T.; Iwan, B.; Seibert, M.; Osipov, T.; Walter, P.; Hart, P.; Bucher, M.; Ulmer, A.; Ray, D.; Carini, G.; Ferguson, K. R.; Andersson, I.; Andreasson, J.; Hajdu, J.; Maia, F. R. N. C.

doi:10.1101/453456

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bioRxiv · 10.1101/453456

Electrospray sample injection for single-particle imaging with X-ray lasers

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Abstract

The possibility of imaging single proteins constitutes an exciting challenge for X-ray lasers. Despite encouraging results on large particles, imaging small particles has proven to be difficult for two reasons: not quite high enough pulse intensity from currently available X-ray lasers and, as we demonstrate here, contamination of the aerosolised molecules by non-volatile contaminants in the solution. The amount of contamination on the sample depends on the initial droplet-size during aerosolisation. Here we show that with our electrospray injector we can decrease the size of aerosol droplets and demonstrate virtually contaminant-free sample delivery of organelles, small virions, and proteins. The results presented here, together with the increased performance of next generation X-ray lasers, constitute an important stepping stone towards the ultimate goal of protein structure determination from imaging at room temperature and high temporal resolution.

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Bielecki, J., Hantke, M. F., Daurer, B. J., Reddy, H. K. N., Hasse, D., Larsson, D. S. D., Gunn, L. H., Svenda, M., Munke, A., Sellberg, J. A., Flueckiger, L., Pietrini, A., Nettelblad, C., Lundholm, I., Carlsson, G., Okamoto, K., Timneanu, N., Westphal, D., Kulyk, O., Higashiura, A., van der Schot, G., Loh, D., Wysong, T. E., Bostedt, C., Gorkhover, T., Iwan, B., Seibert, M., Osipov, T., Walter, P., Hart, P., Bucher, M., Ulmer, A., Ray, D., Carini, G., Ferguson, K. R., Andersson, I., Andreasson, J., Hajdu, J., Maia, F. R. N. C.. 2018-10-26. Electrospray sample injection for single-particle imaging with X-ray lasers. https://doi.org/10.1101/453456

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