Orthogonal Surface-Enhanced Raman Scattering/Field-Effect Transistor Detection of Breast and Colorectal Cancer-Derived Exosomes using Graphene as a Tag-Free Diagnostic Template

Cancer is one of the leading causes of high mortality worldwide, affecting most of the body organs including the breast and colon. Triple-negative breast (TNBC) and colorectal cancers (CRC) usually present the poorest clinical outcomes and lowest disease-free survival rates among the different cancer types. Novel biomarkers for early detection of TNBC and CRC have been proposed throughout the years, although the rate of success remains limited. Herein, a dual method for detection of cancer-derived exosomes based on the measurement of the Raman spectra in graphene field-effect transistors (GFETs) is proposed, thereby obtaining electrical signal metrics related to the variation of the Dirac point in graphene and optical features corresponding to representative bio-molecular cancer structures in an orthogonal way. This pioneering method and classification routine can potentially be extended to other types of cancer, thus creating a unique and universal tag-free diagnostic template for early cancer diagnostics.