A Two‐Stage Dissociation System for Multilayer Imaging of Cancer Biomarker‐Synergic Networks in Single Cells

Abstract The monitoring of cancer biomarkers is crucial to the early detection of cancer. However, a limiting factor in biomarker analysis is the ability to obtain the multilayered information of various biomarker molecules located at different parts of cells from the plasma membrane to the cytoplasm. A two‐stage dissociation nanoparticle system based on multifunctionalized polydopamine‐coated gold nanoparticles (Au@PDA NPs) is reported, which allows for the two‐stage imaging of cancer biomarkers in single cells. We demonstrate the feasibility of this strategy on sialic acids (SAs), p53 protein, and microRNA‐21 (miRNA‐21) in MCF‐7 breast cancer cells by two custom‐built probes. Furthermore, the multicolor fluorescence information extracted is used for the monitoring of biomarker expression changes under different drug combinations, which allows us to investigate the complex interactions between various cancer biomarkers and to describe the cancer biomarker‐synergic networks in single cells.