Multifunctional Ru(III)/Fe₃O₄/DNA nanoplatform for photothermal-enhanced photodynamic and chemodynamic cancer therapy

Among the many cancer treatment methods, there have been many reports on the use of nanoplatforms with single treatment methods such as photothermal, photodynamic or chemodynamic for cancer treatment. In this study, Ru(III) with photodynamic effect and Fe₃O₄ nanoparticles with photothermal and chemodynamic effects are connected through long DNA chains with efficient active targeting rolling circle amplification to construct Ru(III)/Fe₃O₄/DNA nano-platform realizes the combination of photothermal, photodynamic and chemodynamic treatment, which significantly improves the therapeutic effect of the nano-platform. Its multiple active targeting capabilities reduce the damage to normal cells. Ru(III) has excellent photodynamic effect and can catalyze the respiration product NADH (Nicotinamide adenine dinucleotide)to produce highly oxidizing H₂O₂. Fe₃O₄ NPs has weak absorption at 808 nm indicates that it can perform mild photothermal treatment, and the Fe²⁺ in it can react with H₂O₂ to produce ·OH and participate in chemodynamic treatment. Each repeating unit on the rolling circle amplified DNA long chain is connected to the AS1411 aptamer that can actively target cancer cells. Unlike the passive targeting of other nanomedicines, active and efficient targeting is achieved, and a small amount of drugs can achieve high efficacy. The therapeutic effect also reduces the damage to normal cells. The comprehensive killing effect of Ru(III)/Fe₃O₄/DNA can reach 85.1 %. Its high targeting of cancer cells can also be used for imaging detection of cancer cells. This new nanoplatform provides an idea for the synergy of multiple cancer treatments.