Screening and multiple detection of cancer exosomes using an SERS-based method.

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Analytical Chemistry

Background:

• Exosomes are crucial cancer biomarkers increasingly utilized in cancer diagnostics.
• Current diagnostic methods for exosomes can be limited in scope and efficiency.
• Surface-enhanced Raman spectroscopy (SERS) offers high sensitivity for molecular detection.

Purpose of the Study:

• To develop a SERS-based method for screening and simultaneous multiple detection of exosomes.
• To utilize magnetic substrates and aptamer-functionalized SERS probes for exosome capture and identification.
• To validate the method's efficacy in real blood samples for clinical cancer screening.

Main Methods:

• Fabrication of magnetic nanobeads coated with gold and modified with aptamers for exosome capture (targeting CD63).
• Design of SERS probes using gold nanoparticles functionalized with Raman reporters and specific aptamers.
• Simultaneous detection strategy involving mixing capturing substrates with multiple SERS probes to form apta-immunocomplexes.

Main Results:

• The SERS method successfully captured and detected exosomes using aptamer-modified magnetic nanobeads.
• Simultaneous detection of multiple exosome types was achieved by employing distinct SERS probes.
• A decrease in SERS signal intensity in the supernatant indicated the presence of target exosomes.
• The method demonstrated successful application in detecting exosomes within real blood samples.

Conclusions:

• The proposed SERS-based method provides a sensitive and specific platform for exosome detection.
• This approach facilitates simultaneous screening and multiplexed detection of various exosome types.
• The successful validation in blood samples highlights its potential as a promising tool for clinical cancer screening.