High-Precision Profiling of Sialic Acid Expression in Cancer Cells and Tissues Using Background-Free Surface-Enhanced Raman Scattering Tags.

Precise profiling of the sialic acid (SA) expression on the membrane of cancer cells is critical for early identification of cancers and assessment of cancer metastasis. However, the complex physiological environments often result in false positives with currently available imaging technologies. Herein, we have established a background-free surface-enhanced Raman scattering (SERS) imaging platform that allows high-precision profiling of SA expression in cancer cells and differentiation of clinically relevant cancer tissues with various metastasis degrees. Three-dimensional Raman imaging technique provided a deeper insight into visualizing the probe distribution and thus the SA expression at the single-cell level, without destructing the cells. This noninvasive, high-precision imaging technique could favor early diagnosis, staging, and monitoring therapeutic responses of cancers that are highly essential in clinical settings.