Rapid and specific detection nanoplatform of serum exosomes for prostate cancer diagnosis

Tumor exosomes that inherit specific molecules from their parent cells are emerging as ideal biomarkers in cancer diagnostics. Most currently available exosome isolation and detection methods are time-consuming and non-specific; thus, rapid and specific exosome detection methods are needed both clinically and in research. Here, a dual-functional platform is reported composed of reversible conjunction and off-on signal responses. Fe3O4@SiO2@TiO2 particles with high affinity were applied to capture exosomes, and model exosomes could be isolated from solution within 20 min with a capture efficiency of 91.5%. An on-off' fluorescence response PSMA aptasensor was constructed with improved selectivity to detect tumor exosomes by recording the fluorescence intensity with lambda(ex/em )= 557/580 nm. The standard curve for detecting tumor exosomes with the aptasensor was calculated as y = 371.7x + 66.17, ranging from 0.05 to 1 x 10(4) particles/mu L, with R-2 = 0.9737, and a detection limit of 5 x 10(2) particles/mu L in solution. This method was successfully applied to clinical samples, and the results showed better performance in distinguishing prostate cancer patients and healthy samples than the traditional nanoparticle-tracking analysis (NTA) method. This rapid and accurate detection method for prostate cancer may aid in rapid clinical diagnosis.

Automated summary

A dual-functional platform using reversible conjunction and off-on signal responses was developed for rapid and specific detection of tumor exosomes. The platform utilized Fe3O4@SiO2@TiO2 particles to capture exosomes and constructed a fluorescence aptasensor for detecting tumor exosomes with improved accuracy. This method showed better performance in distinguishing prostate cancer patients and healthy samples compared to traditional nanoparticle-tracking analysis (NTA) method.