Bi-doped carbon quantum dots functionalized liposomes with fluorescence visualization imaging for tumor diagnosis and treatment

Liposomes are one of the significant classes of antitumor nanomaterials and the most successful nanomedicine drugs in clinical translation. However, it is difficult to accurately reveal liposome delivery modes and drug release rates at different pH values to assess the biodistribution and drug delivery pathways in vivo. Here, we established a strategy to integrate Bi-doped carbon quantum dots (CQDs) with liposomes to produce fluorescence visualization and therapeutic effects, namely lipo/Bi-doped CQDs. Lipo/Bi-doped CQDs show good water solubility and physicochemical properties, which can be used for in vitro labeling of colon cancer (CT26) cells and in vivo imaging localization tracking tumors for monitoring. Simultaneously, thanks to the excellent pH sensitivity and ion doping characteristic of Bi-doped CQDs, lipo/Bi-doped CQDs can be used to reveal the drug release rate of liposomes at different pH values and exhibit potential effects in vivo antitumor therapy.