As an efficient, noninvasive, and high spatiotemporal resolved approach,
photodynamic therapy (
PDT) has high therapeutic potential for
cancer treatment, whereas its development still faces a number of challenges, such as the lack of efficient and stable
photosensitizers (PSs) and the inadequate ability of PSs to accumulate at
tumor sites and target responses. Herein, a pH-responsive
calcium carbonate (CaCO3)-mineralized AIEgen nanoprobe was prepared by using
bovine serum albumin as the skeleton and loaded with a mitochondria-specific aggregation-induced emission (AIE)-active PS of 1-methyl-4-(4-(1,2,2-triphenylvinyl)styryl)quinolinium
iodide (TPE-Qu+), which exhibits superior
singlet oxygen (1O2)-generation ability and meanwhile possesses a bright near-infrared fluorescence emission. The biomineralized nanoparticles have small sizes (100 ± 10 nm) with good water dispersion and stability. With an increase in acidity (pH = 7.4-5.0), the internal TPE-Qu+ molecules are released gradually and accumulated in the mitochondria due to their hydrophobicity and electropositivity and then generate fluorescence emission and
PDT under an external light source.
Tumor inhibition and low acute toxicity were further successfully confirmed by the intracellular uptake test and 4T1-tumor-bearing mouse model.