Carbon dots-mediated synthesis of gold nanodendrites with extended absorption into NIR-II window for in vivo photothermal therapy

Abstract

Background Photothermal therapy (PTT) in the second near-infrared (NIR-II) window has attracted extensive attention due to the benefits in high maximum permissible exposure and penetration depth. Current photothermal agents generally show a broadband absorption accompanied by a gradual attenuation of absorption in the NIR-II window, leading to poor effect of PTT. It remains a great challenge to gain photothermal agents with strong and characteristic absorption in NIR-II regions. To overcome this problem, based on carbon dots (CDs)-mediated growth strategy, we proposed a simple and feasible approach to prepare plasmonic gold nanodendrites (AuNDs) with NIR-II absorption to enhance the therapeutic effect of PTT. Results By rationally regulating the size and branch length of AuNDs, the AuNDs exhibited a broadband absorption from 300 to 1350 nm, with two characteristic absorption peaks located at 1077 and 1265 nm. The AuNDs demonstrated desired optical photothermal conversion efficiency (38.0%), which was further applied in NIR-II photoacoustic imaging (PAI) and PTT in human colon cancer cells (HCT 116)-tumor-bearing mice model. The tumor cells could be effectively eliminated in vivo under 1064 nm laser irradiation by the guidance of PAI. Conclusions We reported a simple but powerful synthetic method to obtain the unique AuNDs with strong and characteristic absorption peaks in the NIR-II window. This study provides a promising solution to tuning the growth of nanoparticles for bioimaging and phototherapy in the NIR-II window. Graphical Abstract

Zero-Dimensional Carbon Nanomaterials for Fluorescent Sensing and Imaging

“…Mu et al prepared plasmonic gold nanoderivatives (AuNDs) based on the synthesis of CDs-mediated AuNDs with good PCE and effective in vivo clearance of tumor cells under 1064 nm laser irradiation guided by PA. This study not only provides a new method for AuNDs preparation but also facilitates their study via PTT within the NIR-II window …”

“…In addition, the Au NCs and CQDs composited sensor can be converted into a low-cost paper strip sensor to accurately detect I − , which exhibits a wide range of applications to assess the health level of I − in urine. 761 Because of the convenience of injectable hydrogels, Wang et al prepared an injectable hydrogel that can be used for PDT and PTT via the Schiff base reaction of amino-modified CQDs with acetal-modified cellulose nanocrystals, achieving an ultrahigh photothermal efficiency of 77.6% under 660 nm light irradiation, thus proving that this procedure can be effectively used to inhibit tumor growth process (Figure 25f). 762 Zhou et al used chitosan and fluorescent CQDs integrated into nanostructures and reported that CHS-CQDs nanogels, which exhibit stable fluorescence emission from visible to NIR wavelength range, can carry doxycycline into implanted tumors in mice, effectively releasing drug molecules and generating photothermal irradiation to inhibit tumor growth.…”

Stimuli-Responsive Polymeric Nanomedicine for Enhanced Cancer Immunotherapy

“…85 Liu et al synthesized gold nanodendrites (AuNDs) based on carbon dot (CD)-mediated growth, followed by PEGylation to enhance the stability. 86 Two-dimensional black phosphorus (BP) has been suggested as an ideal candidate for PTT because of its good electrical conductivity, high PCE, and low cytotoxicity. Zhang et al reported BP nanoparticles modified with PEGylated HA (HA-BP) for PTT, photodynamic therapy (PDT), and photoimmunotherapy.…”

Sustainable approach to synthesis of carbon Dot/ silver nanoparticles for biological evaluation as antimicrobial agent

“…This is because there are abundant oxygen rich functional groups (carbonyl, carboxyl, epoxy and hydroxyl,) on the CDs surface [20,21]. In particular, fluorescent CDs were exploited as stabilizing, protecting, and reducing agent for the preparation of various metal nanoparticles including silver (Ag), gold (Au) nanoparticles (NPs) [18,22]. In particular AgNPs have widely used in microbicidal applications against bacteria, fungus, and virus [23].…”