Label-free single-molecule digital Raman assay for quantification of low abundance biomarkers (DigiRaman)

Current protein analysis and sequencing relies mainly on mass spectroscopy that generally requires 1 million copies of proteins. The low sensitivity of mass spectroscopy faces a significant challenge in analyzing trace amount of biomarkers in human biofluids in early stage of diseases and the small amount of low-abundance proteins in single cells. This DigiRaman project aims to develop a novel single-molecule digital Raman assay to first identify and then quantify low-abundance biomarkers. Based on our plasmonic nanogap biosensor, the project will be conducted by integrating single-particle manipulation technique, nanogap-enhanced Raman spectroscopy, active feedback control with machine learning analysis. The technology developed by this project can be the key technologies for single-cell proteomics and diagnostic devices for early diagnosis of diseases.