Controllable generation of nitric oxide by near-infrared-sensitized upconversion nanoparticles for tumor therapy

NaYbF₄:Tm@NaYF₄:Yb/Er upconversion nanoparticles are synthesized and then integrated with light-sensitive nitric oxide (NO) donors (Roussin's black salt) to construct a novel near-infrared (NIR)-triggered on-demand NO delivery platform. This nanocompound can absorb 980 nm NIR photons, convert them into higher energy photons and then transfer the energy to the NO donors, resulting in an efficient release of NO. By manipulating the output power of the 980-nm NIR light, NO-concentration-dependent biological effects for cancer therapy can be fine-tuned, which is investigated and confirmed in vitro. High concentrations of NO can directly kill cancer cells and low concentrations of NO can act as a potent P-glycoprotein (P-gp) modulator to overcome multi-drug resistance (MDR) if combined with chemotherapy. A new near-infrared triggered on-demand nitric oxide (NO) delivery nanoplatform is constructed by incorporating upconversion nanoparticles with light-sensitive NO donors, Roussin's black salt (RBS). By regulating the output power of the laser, the on-demand release of NO is realized and results in multi-functionality of NO for tumor therapy.