Dual-color imaging of lipid droplets and lysosomes with triphenylamine-phenyl silicon phthalocyanine nanoprobes for enhanced photodynamic therapy

Abstract

Lipid droplets (LDs), vital in cancer cell metabolism, are prevalent in malignant tumors. Elucidating their interaction with lysosomes is essential for understanding their metabolic functions. However, simultaneous dual-color imaging and photodynamic function targeting both LDs and lysosomes using fluorescent probes remain unexplored. Our study fills this gap with DSPE@TPA-SiPc, a biocompatible nanoparticle that penetrates cells and targets these organelles. Using two-photon imaging, we monitored DSPE@TPA-SiPc in breast cancer cells, noting its plasma membrane dissociation and rapid transport to lysosomes and LDs. DSPE@TPA-SiPc uniquely labeled LDs with blue fluorescence and lysosomes with red, responding to intracellular polarity. Additionally, DSPE@TPA-SiPc induced reactive oxygen species (ROS) in cells, showing enhanced phototoxicity against MDA-MB-231 cells with larger LDs than MCF-7 cells. This research introduces a novel dual-labeled probe for organelle imaging and a promising strategy for targeted cancer therapy.