ERBB2 and neoplasm: Using a similarmethod, SERS imaging of EGFR and human epidermal growth factor 2 (HER2)on the lumenal surface of the rat esophagus was obtained. The distribution of the tumor-associated surfacebiomarker (CD44) was characterized on the surface of HCT116 cellsusing hyaluronic acid functionalized high narrow nanogap-containingAu@Au core–shell SERS tags. Furthermore,imprinted polymer layers on the SERS probe can act as an artificialantibody and specifically bind with biomolecules in the cells.