Upconversion nanoparticles@AgBiS_(2) core-shell nanoparticles with cancer-cell-specific cytotoxicity for combined photothermal and photodynamic therapy of cancers

UCNPs@AgBiS_(2) core-shell nanoparticles that AgBiS_(2) coated on the surface of upconversion nanoparticles (UCNPs) was successfully prepared through an ion exchange reaction. The photothermal conversion efficiency of AgBiS_(2) can be improved from 14.7% to 45% due to the cross relaxation between Nd ions and AgBiS_(2). The doping concentration of Nd ions played a critical role in the production of reactive oxygen species (ROS) and enhanced the photothermal conversion efficiency. The NaYF4:Yb/Er/Nd@NaYF4:Nd nanoparticles endows strong upcon-version emissions when the doped concentration of Nd ions is 1% in the inner core, which excites the AgBiS_(2) shell to produce ROS for photodynamic therapy (PDT) of cancer cells. As a result, the as-prepared NaYF4:Yb/Er/ Nd@NaYF4:Nd@AgBiS_(2) core-shell nanoparticles showed combined photothermal/photodynamic therapy (PTT/ PDT) against malignant tumors. This work provides an alternative near-infrared light-active multimodal nano-structures for applications such as fighting against cancers.

Antibacterial mechanism and transcriptomic analysis of a nearinfrared triggered upconversion nanoparticles@AgBiS2 for synergetic bacteria-infected therapy

Methicillin-resistant Staphylococcus aureus(MRSA)has become a rising clinical problem as its occurrence has increased due to the overuse and misuse of antibiotics.In this work,upconversion nanoparticles@AgBiS2 core–shell were produced with enhanced photothermal transformation efficiency and ability to produce reactive oxygen species for synergistic photodynamic photothermal and photodynamic antibacterial performance.The nanoparticles exhibit good antibacterial effects in vitro and satisfactory therapeutic performance on healing MRSA-infected wounds in vivo experiments.RNA-sequencing technique has been used to investigate and reveal that photothermal–photodynamic therapy using the nanoparticles can interfere with metabolic processes such as galactose metabolism in MRSA bacteria,destroy the transport system on the surface of MRSA,and affect quorum sensing to hinder the formation of biofilms to achieve effective antibacterial efficacy.It was demonstrated that this work presents an alternative near-infrared photoactive multimodal nanostructure for antibacterial applications.

Evoking robust immunogenic cell death by synergistic sonodynamic therapy and glucose depletion using Au clusters/single atoms modified TiO_(2)nanosheets

Facilitated by reactive oxygen species(ROS)-involved therapies,tumor cells undergo immunogenic cell death(ICD)to stimulate long-term immunity response.However,it is hard to trigger abundant and large-scale ICD for satisfactory cancer immunotherapy.Herein,a multifunctional sonosensitizer that consists of Au single atoms and clusters anchored on TiO_(2)nanosheets(named Au_(S/C)-TiO_(2))is reported for augmented sonodynamic therapy(SDT)and glucose depletion,which ultimately induce robust ICD due to the improved ROS generation and strong endoplasmic reticulum(ER)stress.The synergy effect between Au cluster/single atom with TiO_(2)nanosheets intensifies apoptosis and ICD pathways to inhibit 80%of tumor cells through in vivo analyses.Furthermore,immune cells in vivo analyses verify the effectiveness of Au_(S/C)-TiO_(2)sonosensitizer towards the induction of antitumor immunity.This study thus reveals that simultaneous presence of ROS generation and strong ER stress can efficiently evoke a strong ICD-mediated immune response.