A Label-Free Electrochemical Biosensor Based on Ligand-Receptor Interaction

We demonstrated a label-free electrochemical biosensor for detection of cell surface receptor (CSR) based on ligand-receptor interaction between its corresponding bioactive substance (BS) and the cell membrane receptor. The biosensor was fabricated through layer-by-layer (LBL) deposition method using chitosan (Chi) and bioactive substance conjugated multi-walled carbon nanotubes (MWCNTs-BS). Our optimized CSR detection approach using the designer biosensor yielded a linear detection range wildly from 1 ng/mL to 10,000 ng/mL, achieving the limit of detection (LOD) of 0.106 ng/mL.