Label-free quantitative detection of biomarkers

摘要

A highly sensitive technique for detection and quantification of protein-analyte binding interaction using spectral domain low coherence interferometric technique is implemented. Using this technique, it is possible to study real time interactions by quantifying the changes in optical path length caused by protein-analyte binding. The technique does not require elaborate sensor preparation and calibration. Any coverslip with certain thickness and capability to bind protein can work using this technique. For proof of principle, the interaction between IgG antigen and anti-IgG was studied and quantification of the accumulation of anti-IgG on sensor surface was demonstrated. Additionally, for biological relevance interactions between cancer biomarker EGFr and EGF was also studied and the preliminary results are presented. The potential applications of the label free technique include point-of-care screening of cancer biomarkers and tumor cell adhesion analysis.