Christina Johannsen, Léon Reubsaet and Trine Grønhaug Halvorsen
Section of Pharmaceutical Chemistry, Department of Pharmacy, University of Oslo, Oslo, Norway.
Email: cjoha@uio.no
Efficient and selective sample preparation remains a key bottleneck in bioanalysis for clinical diagnostics and anti-doping applications. While microsampling approaches such as dried blood spots and volumetric absorptive microsampling simplify sample collection, they still require multiple off-line preparation steps prior to LC–MS/MS analysis. This work presents the development and improvement of smart samplers -integrated devices that combine microsampling with immunoaffinity-based sample preparation directly at the point of collection. The smart samplers were produced by using three different chemistries for functionalization of the sampling material and consequent antibody immobilization (Figure 1 “Smart sampler production”), enabling selective on-device analyte enrichment. Applications were demonstrated for protein and peptide biomarkers in clinical bioanalysis, including human chorionic gonadotropin (hCG), as well as for growth hormone–releasing hormone (GHRH) analogs (Figure 1 “Smart sampler use”). Analytical performance was evaluated by LC–MS/MS with respect to selectivity, recovery, precision, limits of detection, and matrix effects.
Across multiple formats, smart samplers showed improved reproducibility, enhanced sensitivity at low analyte concentrations, and significantly reduced sample preparation time compared to conventional microsampling workflows. For example, on-paper affinity sampler achieved a 14-fold increase in analyte capture1, while affinity-functionalized VAMS2 and divinyl sulfone–activated samplers3 demonstrated robust performance for both clinical and anti-doping analytes. Overall, integrating immunoaffinity-based sample preparation into the sampling device streamlines bioanalytical workflows and improves analytical robustness.
Figure 1 Schematic workflows for smart sampler production and use ,exemplified using paper as the sampling material
References
1 Christina Johannsen, Anam ul haq, Léon Reubsaet & Trine Grønhaug Halvorsen. On the spot immunocapture in targeted biomarker analysis using paper‑bound streptavidin as anchor for biotinylated antibodies. Analytical and Bioanalytical Chemistry. 2022, 414:5979–5989. Link
2 Christina Johannsen; Leon Reubsaet & Trine Grønhaug Halvorsen. Revolutionizing biomarker analysis one tip at a time – Coupling antibody to Volumetric Absorptive Microsamplers for sensitive LC-MS analysis. Advances in Sample Preparation. 2024, ISSN 2772-5820. 11. Link
3 Christina Johannsen, Anna Kha Tu Nguyen, Sasha Shabani, Inger Oulie, Siri Dørum, Yvette Dehnes, Leon Reubsaet & Trine Grønhaug Halvorsen. Development of smart samplers and their comparison to dried serum spots for the analysis of growth hormone releasing hormone analogs using LC-HRMS/MS. Manuscript submitted to Advances in Sample Preparation. 2025. Link