posted on 2022-01-27, 21:04authored byJing Su, Shixing Chen, Yanzhi Dou, Zhihan Zhao, Xiaolong Jia, Xianting Ding, Shiping Song
Exosomes
are potential biomarkers, which play an important role
in early diagnosis and prognosis prediction of cancer-related diseases.
Nevertheless, direct quantification of exosomes in biological fluid,
especially in point-of-care tests (POCTs), remains extremely challenging.
Herein, we developed a sensitive and portable electrochemical biosensor
in combination with smartphones for quantitative analysis of exosomes.
The improved double-antibody sandwich method-based poly-enzyme signal
amplification was adopted to detect exosomes. We could detect as low
as 7.23 ng of CD63-positive exosomes in 5 μL of serum within
2 h. Importantly, we demonstrated that the biosensor worked well with
microliter-level serum and cell culture supernatant. The biosensor
holds great potential for the detection of CD-63-expressing exosomes
in early diagnosis of prostate disease because CD63-positive exosomes
were less detected from the prostate patient serum. Also, the biosensor
was used to monitor the secretion of exosomes with the drug therapy,
showing a close relationship between the secretion of exosomes and
the concentration of cisplatin. The biosensing platform provides a
novel way toward POCT for the diagnosis and prognosis prediction of
prostate disease and other diseases via biomarker expression levels
of exosomes.