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When nanoparticles (NPs) are dispersed in a biofluid, they are covered by a protein corona the composition of which strongly depends on the protein source. Recent studies demonstrated that the type of disease has a crucial role in the protein composition of the NP corona with relevant implications on personalized medicine. Proteomic variations frequently occur in cancer with the consequence that the bio-identity of NPs in the blood of cancer patients may differ from that acquired after administration to healthy volunteers. In this study we investigated the correlation between alterations of plasma proteins in breast, gastric and pancreatic cancer and the biological identity of clinically approved AmBisome-like liposomes as determined by a combination of dynamic light scattering, zeta potential analysis, one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (1D-SDS-PAGE) and semi-quantitative densitometry. While size of liposome-protein complexes was not significantly different between cancer groups, the hard corona from pancreatic cancer patients was significantly less negatively charged. Of note, the hard corona from pancreatic cancer patients was more enriched than those of other cancer types this enrichment being most likely due to IgA and IgG with possible correlations with the autoantibodies productions in cancer. Given the strict relationship between tumor antigen-specific autoantibodies and early cancer detection, our results could be the basis for the development of novel nanoparticle-corona-based screening tests of cancer.

This work describes the development and the application of a lateral flow biosensor for the detection of the prostate specific antigen in urine (uPSA). The biosensor allowed uPSA detection in 10 minutes with a limit of detection and a range of quantification respectively of 20 ng mL-1 and 37 – 420 ng mL-1, showing within and between-day coefficients of variation ≤ 13%. It showed 92% of accuracy and an almost perfect concordance with the reference electrochemiluminescence immunoassay method. The biosensor design provides the disappearance of the Test line signal at the cut-off concentration. This was achieved with a double layer sensing strategy, in which gold nanoparticles were functionalized with Staphylococcal protein A – a mediator – instead of anti-PSA antibody. This strategy allow making a fine-tune on the concentration of the specific antibody, obtaining an on/off switch of the Test line at the cut-off value. The cut-off value was also established in this work, based on the distribution of uPSA levels from 140 patients, who were suspected of prostate cancer and who underwent to first biopsy. The clinical application of the biosensor to predict repeat biopsy outcome in 28 patients showed sensitivity, specificity, positive and negative predictive values of 100%, 64%, 74% and 100%, respectively.