Surface-enhanced Raman spectroscopy (SERS) technology is increasingly being adopted in biomedical analysis and imaging. A group of researchers at the University of Padova, Italy recently adopted the technology to capture and analyze tumor cells in peripheral blood. Cancer cells released from the primary tumor into the lymphatic system or in the bloodstream have the potential to invade and proliferate in tissues and organs, originating metastatic growths. Early detection is a powerful weapon in physicians’ arsenal and can boost the efficacy of targeted treatments.
Surface-enhanced Raman spectroscopy (SERS) technology is an efficient and sensitive detection method. It overcomes some of the challenges associated with the low abundance of circulating cancer cells and has multiplexing potential. The signal intensities can be further amplified by surface-enhanced resonance Raman scattering (SERRS) and are not affected by photobleaching, typically associated with laser-induced fluorescence. SERRS nanostructures were generated for this application using gold nanoparticles. These were linked to dyes and functionalized with antibodies (Abs) targeting specific biomarkers.
The method was validated with blood samples spiked with cancer cells. The cells were captured onto an avidin coated glass slide functionalized with biotinylated antibodies. A FlexWell™ Incubation Chamber was affixed to the glass slide to create smaller compartments in which cells were fixed and incubated with nanostructures. SERRS spectra were acquired with a µ-Raman spectrophotometer.
The results suggest that detection of circulating tumor cells by Surface-enhanced Raman spectroscopy (SERS) could be used for early cancer detection, and for monitoring the evolution of the disease.
Litti L, Colusso A, Pinto M, et al. SERRS multiplexing with multivalent nanostructures for the identification and enumeration of epithelial and mesenchymal cells. Sci Rep. 2020;10(1):15805. Published 2020 Sep 25. doi:10.1038/s41598-020-72911-w