Surface plasmon resonance biosensor using hydrogel-AuNP supramolecular spheres for determination of prostate cancer-derived exosomes

Based on the hydrogel-AuNP supramolecular sphere (H-Au), a label-free and real-time surface plasmon resonance imaging biosensor has been developed for highly sensitive and specific determination of prostate cancer cell-derived exosomes. After integrating the signal amplification effect of the mass cumulative hydrogel and the LSPR effect of AuNPs with high specific aptamer, the SPRi biosensor for exosome detection exhibited a wide linear range from 1.00 × 10⁵ to 1.00 × 10⁷ particles/mL with a limit of detection of 1.00 × 10⁵ particles/mL. Most importantly, with a strong correlation between the SPRi signal and the t-PSA value measured by the clinical chemiluminescence immunoassay, this biosensor displayed excellent practicability for human serum analysis, which exhibits great potential applications in disease diagnosis and bioanalysis. Graphical abstract: