posted on 2022-08-01, 07:29authored byXiaona Bu, Huijie Wang, Fang Zhang, Qixian Li, Jingru Zhu, Juan Ding, Jie Sun, Yang Liu, Tingting Jiang
One challenge in the field of photothermal therapy (PTT)
is to
design an assembly of carbon nanodots (CNDs) with enhanced light absorption
in the near-infrared (NIR) spectral region and improved photothermal
conversion efficiency. Herein, a type of CND assembly was fabricated
using a covalent click reaction in a water-in-oil emulsion system
(abbreviated as W/O assembly), providing excellent stability, controllable
size distributions, enhanced NIR absorption, and improved applications
in photothermal imaging (PTI), photoacoustic imaging (PAI), and PTT.
A mechanism based on energy dissipation was proposed in detail to
explain the changes in photophysical properties before and after CND
assembly. In addition, an outstanding antibacterial effect was also
observed during the in vitro phototherapy of drug-resistant pathogens.
Importantly, the results of in vivo infection assays further verified
satisfying photokilling effect toward drug-resistant bacteria and
excellent biosafety to normal cells and tissues. Given the benefits
of the covalent CND assembly developed in this work, it might have
potential applications in the following aspects: (1) strategy of the
controllable covalent assembly could be extended to other nanosystems
and (2) in situ CND assembly could be built at disease sites based
on microenvironment-triggered bioorthogonal click reactions, improving
targeting performance and reducing the side effects of PTT.