Quantitaive and specific detection of exosomal miRNA using surface-enhanced Raman spectroscopy for accurate diagnosis of breast cancer

摘要

Recent studies have shown that exosomal miRNAs have an important role in carcinogenesis by targeting cellular growth pathways that enhance intercellular communication and promote metastasis in cancers. Furthermore, miRNAs in exosome are circulating stably in body fluids. As such, exosomal miR.NAs have become an ideal and non-invasive biomarker for the early diagnosis and prognosis. Herein, we developed an ultra-high sensitivity and selectivity nanoplasmonic biosensor based on surface-enhanced Raman scattering (SERS) using head-flocked gold nanopillar substrate for the attomolar detection of cancer-derived exosomal miRNA. SERS nanoplasmonic biosensor showed an ultra-low detection limit of attomolar as well as wide dynamic range of from 1aM to 100nM for target exosomal miRNAs without any amplification step. In addition, this system could discriminate between miRNAs with high sequence similarities, even a single base mismatch. We anticipate that proposed biosensor offers great promise for the precise diagnosis and prognosis of cancer in clinical fields.