The biofilm-mediated implant infections pose a huge threat to human health. It is urgent to explore strategies to reverse this situation. Herein, we design 3-amino-1,2,4-triazole-5-thiol (ATT)-modified gold nanoclusters (AGNCs) to realize biofilm-targeting and near-infrared (NIR)-II light-responsive antibiofilm therapy. The AGNCs can interact with the bacterial extracellular DNA through the formation of hydrogen bonds between the amine groups on the ATT and the hydroxyl groups on the DNA. The AGNCs show photothermal properties even at a low power density (0.5 W/cm2) for a short-time (5 min) irradiation, making them highly effective in eradicating the biofilm with a dispersion rate up to 90 %. In vivo infected catheter implantation model demonstrates an exceptional high ability of the AGNCs to eradicate approximately 90 % of the bacteria encased within the biofilms. Moreover, the AGNCs show no detectable toxicity or systemic effects in mice. Our study suggests the great potential of the AGNCs for long-term prevention and elimination of the biofilm-mediated infections.

Depression is a significant global health concern that remains inadequately treated due to the limited effectiveness of conventional drug therapies. One potential therapeutic agent, hypericin (HYP), is identified as an effective natural antidepressant. However, its poor water solubility, low bioavailability, and limited ability to penetrate the brain parenchyma have hindered its clinical application. To address these shortcomings and enhance the therapeutic efficacy of HYP, it is loaded onto black phosphorus nanosheets (BP) modified with the neural cell-targeting peptide RVG29 to synthesize a nanoplatform named BP-RVG29@HYP (BRH). This platform served as a nanocarrier for HYP and integrated the advantages of BP with advanced delivery methods and precise targeting strategies. Under the influence of 808 nm near-infrared irradiation (NIR), BRH effectively traversed an in vitro BBB model. In vivo experiments validated these findings, demonstrating that treatment with BRH significantly alleviated depressive-like behaviors and oxidative stress in mice. Importantly, BRH exhibited an excellent safety profile, causing minimal adverse effects, which highlighted its potential as a promising therapeutic agent. In brief, this novel nanocarrier holds great promise in the development of antidepressant drugs and can create new avenues for the treatment of depression.

Optimize the separation and transport mechanism of photogenerated carriers in heterojunction composites, and make full use of the active sites of each material are key factors to enhance photocatalytic activity. Herein, we successfully synthesize defective CdLa2S4@La(OH)3@Co3S4 (CLS@LOH@CS) Z-scheme heterojunction photocatalysts through a facile solvothermal method, which show broad-spectrum absorption and excellent photocatalytic activity. La(OH)3 nanosheets not only greatly increase the specific surface area of photocatalyst, but also can be coupled with CdLa2S4 (CLS) and form Z-scheme heterojunction by converting irradiation light. In addition, Co3S4 with photothermal properties is obtained by in-situ sulfurization method, which can release heat to improve the mobility of photogenerated carriers, and also be used as a cocatalyst for hydrogen production. Most importantly, the formation of Co3S4 leads to a large number of sulfur vacancy defects in CLS, and thus improving the separation efficiency of photogenerated electrons and holes, and increasing the catalytic active sites. Consequently, the maximum hydrogen production rate of CLS@LOH@CS heterojunctions can reach 26.4 mmol g-1h-1, which is 293 times than pristine CLS (0.09 mmol g-1h-1). This work will provide a new horizon for synthesizing high efficiency heterojunction photocatalysts through switching the separation and transport modes of photogenerated carrier.

Conferring versatility to superhydrophobic materials is extremely desirable to advance their utility. Herein, we have developed a superhydrophobic material with montmorillonite as microskeleton supports and in situ grown ZIF-8 nanoparticles and loaded them with newly developed fluorescent carbon dots. In situ growth of the ZIF-8 on OMMT constructs a dense nanoscale rough structure and meanwhile self-assembly generates abundant microporous, thus forming unique hierarchical microporous/microsheet/nanoparticle tri-tier micro and nano structures. Then the multifunctional superhydrophobic coating is fabricated by a facile spraying technique using polydimethylsiloxane (PDMS) as a multifunctional polymer binder. The PDMS/RB-CDs/ZIF-8@OMMT exhibits superhydrophobicity with a water contact angle of 164.7° and a water sliding angle of 1.4°, which also possesses good self-cleaning performance. Moreover, novel carbon dots are developed in this work which can confer unique fluorescent properties and photothermal properties to materials. Fluorescence characterization reveals the multiple emission peaks among 300-800 nm and excitation wavelength dependence and independence. Photothermal experiments unveil an efficient light-to-heat conversion caused by the light traps and absorption wavelengths associated with photothermal heating. Benefiting from the dense microporous/microsheet/nanoparticle structures, the superhydrophobicity is still maintained after 120 cycles of abrasion. Moreover, electrochemical impedance spectroscopy (EIS) reveals a significant increase in impedance, which is associated with excellent corrosion resistance. The superhydrophobic coating also exhibits superior UV resistance and good thermal stability. Multifunctional fluorescent superhydrophobic materials will enable the development of various and potential applications in different fields.

The development of smart hydrogel with excellent mechanical properties and photothermal conversion capability is helpful in expending its application fields. Herein, a MXene/gelatin/polyacrylamide (M/G/PAM) nanocomposite double network (NDN) hydrogel was synthesized by γ-ray radiation technology for the first time. Compared with gelatin/polyacrylamide double network hydrogel, the optimized resultant M3/G/PAM NDN hydrogel shows better mechanical properties (tensile strength of 634 ± 10 kPa, compressive strength of 3.44 ± 0.12 MPa at a compression ratio of 90%). The M3/G/PAM NDN hydrogel exhibits a faster heating rate of 30 °C min-1, stable photothermal ability, and mechanical properties even after 20 cycles of on-off 808 nm near-infrared (NIR) laser irradiation (1.0 W cm-2). Furthermore, the temperature of M3/G/PAM NDN hydrogel can be increased rapidly from 25 °C to 90 °C in 10 s and could reach 145 °C in 120 s under irradiation by focused NIR laser irradiation (56.6 W cm-2). The high mechanical property and photothermal properties of M/G/PAM hydrogel are ascribed to the formation of double network and uniform hydrogen bonding between MXene and gelatin and PAM polymers. This work paves the way for construction of photothermal hydrogels with excellent mechanical properties.

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Bacterial resistance caused by antibiotic therapy is a serious problem. Therefore, there is an urgent need to find alternative methods to overcome bacterial resistance. Herein, we synthesized a new type of iridium oxide (IrOx) as an alternative to antibiotics. Iridium oxide not only has good catalytic properties, but also has photothermal properties, and then realizes the \"one body and two wings\" strategy to enhance the antibacterial effect. Research results show that near-infrared light can enhance the peroxidase catalytic activity of IrOx and generate highly toxic hydroxyl radicals (·OH) by catalyzing hydrogen peroxide (H2O2). Hydroxyl radicals have a high redox potential, which can overcome the drug resistance of gram-positive and negative bacteria. Importantly, IrOx has no obvious cellular and in vivo toxicity. Accordingly, the novel photothermal nanozyme is expected to be applied to bacterial infectious diseases, such as wound healing, sepsis, and implant-related infections.

Photothermal conversion agents (PTCAs) based on π-conjugated polymers are promising for cancer therapy, but the alteration of bandgap energies toward boosted photothermal properties remains challenging. Herein, polymer PTCAs with heterojunctions of a binary optical component are developed by interface hybridization on porous particles. Specifically, polypyrrole (PPy) nanodomains are successfully hosted on the wet-adhesive surface of mesoporous polydopamine nanoparticles through the loading and polymerization of pyrrole in the confined pore space (≈5.0 nm). The near-infrared absorbing polymers in the heterojunctions possess similar five-membered heterocyclic rings and can interact mutually to generate photoinduced electron transfer (PET). Such a large-area optoelectronic interaction progressively reduces the bandgap energy (down to 0.56 eV) by increasing the doped amount of PPy, which consequently enhances the extinction coefficient and photothermal conversion efficiency by 4.6- and 2.2-fold, respectively. Notably, the hybrid PTCA exhibits good biocompatibility, photocytotoxicity, and great potential for cancer therapy.

Through fusing isoindigo (IID) units at 6,7;6\',7\'-positions, a series of new near-infrared (NIR) absorbing and stable ribbon-like conjugated molecules, namely nIIDs in which n represents the number of IID units, have been synthesized. The optical band gaps of the molecules are lowered from 2.03 eV of 1IID to 1.12 eV of 6IID with the increase of the conjugation length. 3IID, 4IID, and 6IID have strong absorption in the NIR region and exhibit photothermal conversion efficiencies of greater than 50 % under laser irradiation at λ=808 nm.

A new kind of fast near-infrared (NIR) light-responsive shape-memory polymer composites was prepared by introducing polydopamine particles (PDAPs) into commercial shape-memory polyurethane (SMPU). The toughness and strength of the polydopamine-particle-filled polyurethane composites (SMPU-PDAPs) were significantly enhanced with the addition of PDAPs due to the strong interface interaction between PDAPs and polyurethane segments. Owing to the outstanding photothermal effect of PDAPs, the composites exhibit a rapid light-responsive shape-memory process in 60 s with a PDAPs content of 0.01 wt%. Due to the excellent dispersion and convenient preparation method, PDAPs have great potential to be used as high-efficiency and environmentally friendly fillers to obtain novel photoactive functional polymer composites.