To achieve better specificity to cancer cells, fluorescent dyes or nanoparticles are usually conjugated with tumor-specific biomarkers, such as antibodies.13 For example, cetuximab is a monoclonal antibody that can selectively target to an epidermal growth factor receptor, which is overexpressed in colorectal and breast cancer cells.14,15 Although conjugation of biomolecules to fluorescent dyes can improve the imaging contrast between cancer and normal cells, this method involves complicated molecular design, synthetic step and product purification procedure. Here, EGFR is linked to cancer.