Highly efficient human serum filtration with water-soluble nanoporous nanoparticles

Antonella Pujia¹, Francesco De Angelis^1,2, Domenica Scumaci³, Marco Gaspari³, Carlo Liberale^1,2, Patrizio Candeloro¹, Giovanni Cuda³, Enzo Di Fabrizio^1,2
1BIONEM Laboratory, Department of Experimental and Clinical Medicine, University of Catanzaro “Magna Graecia”, Germaneto (CZ), Italy; ²IIT, Italian Institute of Technology, Genova, Italy; ³Proteomics and Mass Spectrometry Laboratory, Department of Experimental and Clinical Medicine, University of Catanzaro “Magna Graecia”, Germaneto (CZ), Italy

Background: Human serum has the potential to become the most informative source of novel biomarkers, but its study is very difficult due to the incredible complexity of its molecular composition. We describe a novel tool based on biodegradable nanoporous nanoparticles (NPNPs) that allows the harvesting of low-molecular-weight fractions of crude human serum or other biofluids. NPNPs with a diameter of 200 nm and pore size of a few nm were obtained by ultrasonication of nanoporous silicon. When incubated with a solution, the NPNPs harvest only the molecules small enough to be absorbed into the nanopores. Then they can be recovered by centrifugation and dissolved in water, making the harvested molecules available for further analyses.
Results: Fluorescence microscopy, gel electrophoresis, and mass spectrometry were used to show the enrichment of low-molecular-weight fraction of serum under physiological conditions, with a cut-off of 13 kDa and an enrichment factor >50.
Conclusion: From these findings, we conclude that ability to tune pore size, combined with the availability of hundreds of biomolecule cross-linkers, opens up new perspectives on complex biofluid analysis, discovery of biomarkers, and in situ drug delivery.

Keywords: nanoporous silicon, nanoparticle, biomarker discovery, human serum proteomics, harvesting