Y. Yang, N. Gao, Y. Hu, C. Jia, H. Du, H. Wang
Stevens Institute of Technology, United States
pp. 98 - 101
Keywords: photodynamic therapy, gold nanoparticles, mitochondria, reactive oxygen species
Photodynamic therapy (PDT) is an emerging minimally invasive therapeutic modality for a variety of oncologic diseases. In recognition of their superior optical and surface plasmonic properties, gold nanoparticles (Au NPs) can be utilized as the enhancers for PDT by promoting the generation of reactive oxygen species (ROS) under light irradiation. Meanwhile, given that mitochondria are the primary site for photodynamic reaction, together with their crucial roles in regulating cell apoptosis and cancer metabolism, they are of particular interest as potential target for improved PDT efficiency. In present study, we aimed to further improve the efficiency and selectivity of PDT by delivering Au NPs particularly to mitochondria of breast cancer cells. Au NPs with positive surface charge were synthesized and conjugated with mitochondria-targeting triphenylphosphonium (TPP) molecules. Combination of positive surface charge with mitochondria-targeting domain onto Au NPs allowed their accumulation in the mitochondria of breast cancer cells to significantly elevate ROS formation in 5-aminolevulinic acid (5-ALA)-enabled PDT and improve selective destruction of breast cancer cells. Targeted delivery of Au NPs into mitochondria provides an important guidance on the effectiveness of intracellular targeting for further optimization of drug delivery and improvement of therapeutic efficacy.