In situ polymerized monolith tips for reproducible, format-flexible proteomic sample preparation applied to biofluids

Korff, K.; Henneberg, L.; Oliinyk, D.; Eikmeier, N.; Schuele, A. M.; Heymann, T.; Schebesta, A.-S.; Albrecht, V.; Kaiser, C. J. O.; Mann, M.; Mueller-Reif, J. B.

doi:10.64898/2026.06.11.731522

bioRxiv · 10.64898/2026.06.11.731522

In situ polymerized monolith tips for reproducible, format-flexible proteomic sample preparation applied to biofluids

Korff, K.·Henneberg, L.·Oliinyk, D.·Eikmeier, N.·Schuele, A. M.·Heymann, T.·Schebesta, A.-S.·Albrecht, V.·Kaiser, C. J. O.·Mann, M.·Mueller-Reif, J. B.

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Abstract

Sample preparation increasingly sets the throughput and reproducibility of mass spectrometry (MS)-based proteomics. StageTips (stop-and-go extraction tips) and variants thereof have long been common implements to purify samples, and we recently extended the concept to solid-phase extraction capture (SPEC) tips, in which the entire digestion takes place in sub-microliter volumes. Here we replace the hand-packed bed with a strong anion-exchange (SAX) monolith photopolymerized directly inside the pipette tip from a defined recipe (pSPEC). A liquid-handling robot casts 384 tunable tips in minutes, at low cost and in any format, adding negligibly to the workflows variance. Across biofluids, pSPEC added [~]20% more identifications than in-solution plasma and reached 3,500 protein groups from a single injection of healthy urine and 4,800 from saliva at 100 samples per day, depths usually requiring depletion or fractionation. The same light-cast chemistry should extend to single cells, affinity capture, and population-scale studies.

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Korff, K., Henneberg, L., Oliinyk, D., Eikmeier, N., Schuele, A. M., Heymann, T., Schebesta, A.-S., Albrecht, V., Kaiser, C. J. O., Mann, M., Mueller-Reif, J. B.. 2026-06-15. In situ polymerized monolith tips for reproducible, format-flexible proteomic sample preparation applied to biofluids. https://doi.org/10.64898/2026.06.11.731522

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