Synergistic Photodynamic and Photothermal Antibacterial Nanocomposite Membrane Triggered by Single NIR Light Source

Abstract

Herein, we developed a nanocomposite membrane with synergistic photodynamic therapy and photothermal therapy antibacterial effects, triggered by a single near-infrared (NIR) light illumination. First, upconversion nanoparticles (UCNPs) with a hierarchical structure (UCNPs@TiO2) were synthesized, which use NaYF4:Yb,Tm nanorods as the core and TiO2 nanoparticles as the outer shell. Then, nanosized graphene oxide (GO), as a photothermal agent, was doped into UCNPs@TiO2 core–shell nanoparticles to obtain UCNPs@TiO2@GO. Afterward, the mixture of UCNPs@TiO2@GO in poly­(vinylidene) fluoride (PVDF) was applied for electrospinning to generate the nanocomposite membrane (UTG-PVDF). Generation of reactive oxygen species (ROS) and changes of temperature triggered by NIR action were both investigated to evaluate the photodynamic and photothermal properties. Upon a single NIR light (980 nm) irradiation for 5 min, the nanocomposite membrane could simultaneously generate ROS and moderate temperature rise, triggering synergistic antibacterial effects against both Gram-positive and -negative bacteria, which are hard to be achieved by an individual photodynamic or photothermal nanocomposite membrane. Additionally, the as-prepared membrane can effectively restrain the inflammatory reaction and accelerate wound healing, thus exhibiting great potentials in treating infectious complications in wound healing progress.

Mild temperature photothermal assisted anti-bacterial and anti-inflammatory nanosystem for synergistic treatment of post-cataract surgery endophthalmitis

“…As a transparent optical organ of eyeball, phototherapy has broad prospects on the ophthalmic disease. Phototherapy, including photothermal therapy (PTT) and photodynamic therapy (PDT), are widely used to treat infections and exhibit a distinct advantage over conventional chemical antimicrobial agents 27 . Considering the complex structure of the eye, a bactericidal strategy of mild temperature photothermal assisted therapy, which remains the antibacterial effect but reduces thermal damage to nearby tissues, is more suitable for endophthalmitis 28 , 29 .…”

Erythrocyte membrane-camouflaged nanoworms with on-demand antibiotic release for eradicating biofilms using near-infrared irradiation

“…When the concentration was greater than 100 μg/mL, the final temperature of RBCM-NW-G reached values as high as 50 °C. This temperature has the ability to sterilize without damaging normal tissues [ 43 , 44 ]. The photothermal effect of particles also depends on the laser density, which in turn, has an important effect on the particle temperature.…”

Recent progress in the development of upconversion nanomaterials in bioimaging and disease treatment

“…The hybrid nanomaterials make a difference in the separation and purification of biomolecules or the design of multimodal bioimaging probes. Noble metals such as a silver shell modified on the surface of UCNPs can enhance UCL efficiency by surface plasmon coupled emission to produce a multimodal hybrid material, which can be used for photothermal therapy [ 121 ]. By adjusting the thickness of the silver layer, the wavelength of the UCNP surface plasmon resonance can be adjusted to 980 nm, and bioimaging by upconversion emission can be performed simultaneously under single wavelength illumination [ 122 ].…”