Core–Shell Multifunctional Nanomaterial-Based All-in-One Nanoplatform for Simultaneous Multilayer Imaging of Dual Types of Tumor Biomarkers and Photothermal Therapy

Versatile all-in-one nanoplatforms that inherently possess both diagnostic imaging and therapeutic capabilities are highly desirable for efficient tumor diagnosis and treatment. Herein, we have developed a novel core–shell multifunctional nanomaterial-based all-in-one nanoplatform composed of gold nanobipyramids@polydopamine (Au NBPs@PDA) and gold nanoclusters (Au NCs) for simultaneous in situ multilayer imaging of dual types of tumor biomarkers (using a single-wavelength excitation) with different intracellular spatial distributions and fluorescence-guided photothermal therapy. The competitive combination between target transmembrane glycoprotein mucin1 (MUC1) and its aptamer caused Au NCs (620 nm) labeled with MUC1 aptamer to detach from the surface of Au NBPs@PDA, turning on the red fluorescence. Meanwhile, the hybridization between microRNA-21 (miRNA-21) and its complementary single-stranded DNA triggered the green fluorescence of Au NCs (515 nm). Based on this, simultaneous in situ multilayer imaging of dual types of tumor biomarkers with different intracellular spatial distributions was achieved. In addition, the potential of Au NBPs@PDA/Au NCs was also confirmed by simultaneous multilayer in situ imaging within not only three cell lines (MCF-7, HepG2, and L02 cells) with different expression levels of MUC1 and miRNA-21 but also cancer cells treated with different inhibitors. Moreover, the remarkable photothermal properties of Au NBPs@PDA resulted in the more efficient killing of cancer cells, demonstrating the great promise of the all-in-one nanoplatform for accurate diagnosis and tumor therapy.