SERS (Surface-Enhanced Raman Scattering) microscopy and Raman fingerprint in Her2 breast cancer cell-lines.

Raman spectroscopy (RS) is a fast, non-invasive, and non-destructive method to study biological matter, counting on the inelastic scattering of light. A laser source is used to generate the scattered photons, collected by a CCD detector. Nowadays, confocal Raman microscopy with sub-micrometric resolution is common instrumentation, allowing super-resolved live imaging on biological samples. Specifically, diagnosing tumor cells is a promising application field of RS, in which a clear and unbiased identification is a challenging issue. In this frame, breast cancer study is one of the main targets of cancer research, in which early-stage diagnosis can dramatically improve the patient's prognosis. In this study, we focused on Her2 protein expression, a malignancy highly correlated breast cancer biomarker. Thus, we have measured the Raman signal of different Her2 expressing cell lines and their Her2 expression levels, by developing a Surface-Enhanced Raman Scattering (SERS) sensor of the Her2 expression. This enabled the same instrumentation to correlate Her2 expression and the biochemical composition of Her2-expressing cancer cell lines.