Copper(II) based low molecular weight collagen fragments-chlorin e6 nanoparticles synergize anti-cancer and anti-bacteria photodynamic therapy.

Copper-based photosensitizer nanoparticle has high potential clinic translation potency for its extensive physiological effects such as anti-cancer progression, anti-bacteria and accelerate tissue regeneration. However, copper excess or improper coordination can induce toxicity or reduce drug efficacy. To get proper copper-photosensitizer complex nanoparticle, a portion of chlorin e6 covalently conjugated with low molecular weight fish collagen fragments-collage tripeptides (CTPs), and Cu subsequently triggers CTP-Ce6 conjugates assemble to Cu(II) based CTP-Ce6 nanosphere(CCeC-Ns). CCeC-Ns are 10-20 nm nanoparticles. CCeC-Ns quenched Ce6 fluorescence in aqueous solution and improved longer wavelength light absorbance. It exhibited dramatically higher cellular uptake rates and much more anticancer potency than those of free Ce6 under 660 nm irradiation without obvious dark toxicity in vitro. CCeC-Ns have longer retention time and higher penetrating rate than free Ce6 in tumor spheroid model. CCeC-Ns displayed extremely higher anti-bacterial potency than free Ce6 and sustainable efficacy. It provides a more potent and safer nanodrug for cancer and infection treatment and an idea for highly efficient metal-photosensitizers complexes design.