High Photothermal Conversion Efficiency Research Articles

Wet chemistry-based processing of tunable polychromatic carbon quantum dots for multicolor bioimaging and enhanced NIR-triggered photothermal bactericidal efficacy

A strategy for the processing of photoluminescence emission tunable multicolor carbon quantum dots has been adopted based on the controllable acidic strength [different ratio mixtures of sulfuric and phosphoric acids (S:P)] using a single polyphenolic precursor. 1,3,5-trihydroxybenzene, a three-fold symmetric (C3h symmetry) triangulogen bearing –OH group at the meta position, was judiciously chosen to undergo dehydration facilitated condensation and carbonization suitably via a tri-molecular reaction route in a dehydrating acid medium. Polyaromatic-polyphenolic CQDs with multicolor emissions [blue (B-CQDs), green (G-CQDs), and yellow (Y-CQDs)] could be rapidly obtained through a facile wet chemistry-based thermal heating process. The mechanism of regulated bottom-up growth of CQD particles involved tri-molecular ring cyclization. These multicolor luminous CQD probes enabled intense multicolor cellular imaging throughout the entire visible range because of their good biocompatibility, photostability, and effective intracellular distribution. Moreover, Y-CQDs with larger polyaromatic sp2 domains and higher oxidized surfaces exhibited a high photothermal conversion efficiency (PCE ∼ 32.6 ± 1 %) and thus exhibited remarkable NIR-light responsive photothermal bactericidal activity. Our results demonstrate that hyperthermia-induced bactericidal activity is due to the elevated reactive oxygen species (ROS) amplification and membrane damage of Bacillus subtilis. This study provides a potential alternative for the multicolor imaging guided CQDs-based phototheranostic.

A Strategy to Design Cu2MoS4@MXene Composite With High Photothermal Conversion Efficiency Based on Electron Transfer Regulatory Effect.

Using photothermal therapy to treat cancer has become an effective method, and the design of photothermal agents determines their performance. However, due to the major radiative recombination of a photogenerated electron in photothermal materials, the photothermal performance is weak which hinders their applications. In order to solve this issue, preventing radiative recombination and accelerating nonradiative recombination, which can generate heat, has been proved as a reasonable way. We demonstrated a Cu2MoS4@MXene nanocomposite with an obviously enhanced photothermal conversion efficiency (η = 87.98%), and this improvement can be attributed to the electron migration. Then, a mechanism is proposed based on the electron transfer regulatory effect and the localized surface plasmon resonance effect, which synergistically promote nonradiative recombination and generate more heat. Overall, our design strategy shows a way to improve the photothermal performance of Cu2MoS4, and this method can be extended to other photothermal agents to let them be more efficient in treating cancer.

Preparation and multiple applications of integrated Zn-Al layered double hydroxide@polydopamine nanocomposites

The preparation and application of inorganic-organic hybrid nanomaterials is a hot research topic at present. Herein, we combined Zn-Al layered double hydroxide (Zn-Al LDH) with mesoporous polydopamine (MPDA) to prepare two integrated Zn-Al LDH@MPDA nanocomposites under the modification of linker (1,3,5-benzoyl chloride (TMC) or (3-aminopropyl) trimethoxysilane (APTMS)), namely Composite T (modified by TMC) and Composite A (modified by APTMS), which were then evaluated for dye adsorption, adriamycin hydrochloride (DOX) loading, photothermal conversion experiment, and antibacterial test. The characterization results showed that MPDA can be successfully loaded on Zn-Al LDH with the modification of the two linkers, but the specific surface area, pore-volume, average pore size, and electronegativity of Composite T were all higher than those of composite A, thus being more advantageous in adsorption of cationic dye. Composite T possesses a high loading capacity for DOX, whose loading efficiency and encapsulation efficiency are 478.3% and 95.7%, respectively. In addition, Composite T also shows a high photothermal conversion efficiency of 27.9%. Furthermore, Composite T exhibits excellent antibacterial activity against Escherichia coli (E. coli) and Staphylococus aureus (S. aureus). Therefore, the designed Zn-Al LDH@MPDA nanocomposites would be a promising candidate for a myriad of industrial application fields.

Tumor microenvironment-responsive nanohybrid for hypoxia amelioration with photodynamic and near-infrared II photothermal combination therapy

Phototherapy, particularly photothermal therapy (PTT) and photodynamic therapy (PDT), has been widely investigated for tumor treatment. However, the limited tissue penetration depth of light in the near-infrared I (NIR-I) region and the hypoxic tumor microenvironment (TME) severely constrain their clinical applications. To address these challenges, in the present study, we developed a chlorin e6 (Ce6) and MnO2-coloaded, hyaluronic acid (HA)-coated single-walled carbon nanohorns (SWNHs) nanohybrid (HA-Ce6-MnO2@SWNHs) for PDT and PTT combination therapy of tumor. HA-Ce6-MnO2@SWNHs responded to the mild acidic TME to ameliorate tumor hypoxia, thus enhancing tumor PDT. Moreover, HA-Ce6-MnO2@SWNHs had a high photothermal conversion efficiency at 1064 nm (55.48%), which enabled deep tissue penetration (3.05 cm) and allowed for highly efficient tumor PTT in near-infrared II (NIR-II) window. PDT and PTT combination therapy with HA-Ce6-MnO2@SWNHs achieved a good therapeutic efficacy on 4T1 tumor-bearing mice, eradicating the primary tumors and suppressing cancer recurrence. Our study provides a promising strategy for developing a hypoxia relief and deep tissue penetration phototherapy platform by using SWNHs for highly effective tumor PDT and NIR-II PTT combination therapy. Statement of SignificanceThe hypoxic tumor microenvironment (TME) and the limited penetration of the NIR-I light in biological tissues compromise the efficacy of photothermal therapy (PTT) and photodynamic therapy (PDT) on tumors. Here, we developed a chlorin e6 (Ce6) and MnO2-coloaded, hyaluronic acid (HA)-coated single-walled carbon nanohorns (SWNHs) nanohybrid (HA-Ce6-MnO2@SWNHs) for PDT and PTT combination therapy of tumors. The nanohybrid could efficiently accumulate in tumors through CD44-mediated active targeting. The sequential MnO2-enhanced PDT and efficient NIR-II PTT had a remarkable therapeutic effect by eliminating the primary tumor and simultaneously inhibiting tumor recurrence.

Self-assembly synthesis of flower-like gold nanoparticles for photothermal treatment of cancer

Polymyxin E (PE) could be used as a soft template, because of its characteristics of self-assembly and ability of metal ions reduction. Here, PE induced gold nanoflowers (PE@AuNFs) were successfully synthesized by seed growth method. PE@AuNFs had anisotropy, large absorption cross section, and large surface plasmon resonance (LSPR) peak, resulting in high photothermal conversion efficiency of 34.9%. Moreover, the cell viability of PE@AuNFs for HeLa cells was 19% under near-infrared light irradiation, while cell viability of 15 nm citrate capped gold nanoparticles (SC@AuNPs) was 83%. PE@AuNFs showed good antibacterial effect with laser irradiation. Furthermore, the excellent inhibition efficacy of PE@AuNFs also was demonstrated in U14 tumor-bearing mice in vivo. Taken together, the flower-shaped PE@AuNFs prepared by this new method had good biocompatibility and outstanding near-infrared photothermal treatment effect, indicating their great potential in photothermal therapy.

Polyimide/phosphorene hybrid aerogel-based composite phase change materials for high-efficient solar energy capture and photothermal conversion

• We developed a new type of composite PCM for high-efficient solar energy capture. • The composite PCM was based on polyimide/phosphorene hybrid aerogel and PEG . • The introduction of phosphorene enhances solar photothermal absorption and conversion. • The composite PCM presents high solar light-to-heat conversion efficiency. • The composite PCM exhibits great potential for efficient utilization of solar energy. Solar energy is the cleanest and most abundant renewable energy source that can be utilized to displace fossil fuels and provide an effective solution for future energy shortage and climate change. Aiming at enhancing the capture efficiency of solar photothermal energy, we developed a novel type of phase-change composites based on polyimide (PI)/phosphorene (PR) hybrid aerogel and polyethylene glycol (PEG). The composites were prepared by fabricating a series of PI/PR hybrid aerogels with different loadings of PR nanosheets using freeze-drying and thermal imidization techniques, followed by vacuum impregnation of PEG as a phase change material into the aerogel framework. The obtained hybrid aerogels exhibited a lightweight nature with a density of 21.9 mg·cm −3 when 16 wt% PR nanosheets were incorporated, resulting in an extremely high PEG loading of 4067% in the aerogel system. The combination of PI and PR nanosheets leads to a significant enhancement in solar light absorption and photothermal energy conversion for the hybrid aerogel/PEG composites. The loading amount of PEG was also improved remarkably due to an increase in the volume capacity of the hybrid aerogels resulting from the introduction of PR nanosheets. The resultant hybrid aerogel/PEG composites not only exhibit a high latent-heat capacity of over 170 J·g −1 and a high photothermal conversion efficiency of 82.5%, but also show good thermal impact resistance to keep their original shape and form well after heating at 80 °C for 20 min and maintain a high thermal cycle stability after thermally cycled for 500 times. These superior performances make the hybrid aerogel/PEG composites capable of dealing with a wide range of applications in solar photothermal energy capture and storage. This study provides a promising strategy for the design and development of high-performance and lightweight composite PCMs to meet the requirement of applications for efficient utilization of solar energy.

Efficient Solar Thermal Energy Conversion and Utilization by a Film of Conductive Metal–Organic Framework Layered on Nanocellulose

Developing materials for efficient solar thermal energy conversion (STEC) is currently a promising field in energy research. Traditional STEC materials such as carbon and plasmonic nanomaterials have limited efficiency of solar heat utilization, despite their high photothermal conversion efficiency. This paper describes a film composed of hybrid nanofibers of a metal–organic framework layered on cellulose (MC film), resulting in both high photothermal conversion and heat utilization efficiency. The mechanically strong and flexible film can be designed as a solar-driven actuator, enabling large-angle actuation and high contractile power up to 2.5 times greater than that of human muscle. Furthermore, the gathered heat by a MC film-based apparatus can be manipulated to drive solar steam generation for highly efficient seawater desalination, generating clean water at rate of 2.25 kg m–2 h–1 under one-sun irradiation without surface salt accumulation. This work may provide a design rule for developing high-performance STEC systems.

Self-assembly hierarchical binary gel based on MXene and montmorillonite nanosheets for efficient and stable solar steam generation

Solar steam generation is an environment-friendly, low-cost, efficient and sustainable approach to produce fresh water, which has been widely researched recently as a promising technology. However, practical application of solar steam generation is always restricted by the photothermal conversion efficiency and long-term stability. Herein, the self-assembly hierarchical binary gel (HBG) containing a MXene (Ti3C2) gel as the upper structure and montmorillonite (MMT) gel as based materials was designed to achieve the efficient solar desalination toward water purification applications. The result indicated that Ti3C2 gel exhibited high light absorption efficiency (over 94%) in a wide solar spectrum range, meanwhile, MMT gel showed remarkable thermal isolation with a low conductivity of 0.04366 (W/m·K) as well as quick water supply ability. In addition, the HBG achieved the evaporation rate of 1.37 kg m−2 h−1 with the high photothermal conversion efficiency of 93.7%. This hierarchical design also performed an excellent stability in cycle tests and salt-rejecting experiments as well as achieved remarkable water purification performance by rejecting organics and metal ions. In a word, the HBG is proved to be an efficient and advanced design with excellent stability for solar steam generation.

Superelastic and robust carbonaceous nanofibrous aerogel with high pressure-sensitivity, excellent thermal insulation and high photothermal-conversion efficiency

Carbonaceous aerogels have attracted extensive research interest due to their impressive physical properties such as high porosity, high electrical conductivity, low thermal conductivity, and low density. However, the low durability of the aerogels under compression is a concern. In this work, superelastic, multimodal porous, chitin-derived carbonaceous nanofibrous aerogel (CAs) whose mechanical properties were tunable were prepared by a facile and cost-efficient carbonization method. The CAs exhibited remarkable elasticity and stability under compression, even under extreme temperatures. After the CAs had been subjected to one loading-and-unloading cycle under the compressive strain (ɛ) of 50%, the CAs exhibited a very low energy-loss coefficient (0.15). Moreover, the CAs maintained their structural integrity with little deterioration of mechanical properties after 1000 cycles. The structural stability and the superelasticity of the CAs conferred the materials a fast and accurate piezoresistive response, which renders it promising for the fabrication of pressure sensor with a high gauge factor (GF, 14.24) under low ɛ (up to 2%). Furthermore, the biomass-derived cost-efficient CAs demonstrated high photothermal-conversion efficiency of solar energy (96.4%) and excellent thermal insulation. Therefore, the CAs exhibit potential applications in the fabrication of pressure sensors, the production of thermal-insulation materials, and the desalination of seawater.

Precise Design of Atomically Dispersed Fe, Pt Dinuclear Catalysts and Their Synergistic Application for Tumor Catalytic Therapy.

Recently, extending single-atom catalysts from mono- to binary sites has been proved to be a promising way to realize more efficient chemical catalytic processes. In this work, atomically dispersed Fe, Pt dinuclear catalysts ((Fe, Pt)SA-N-C) with an ca. 2.38 Å distance for Fe1 (Fe-N3) and Pt1 (Pt-N4) could be precisely controlled via a novel secondary-doping strategy. In response to tumor microenvironments, the Fe-N3/Pt-N4 moieties exhibited synergistic catalytic performance for tumor catalytic therapy. Due to its beneficial microstructure and abundant active sites, the Fe-N3 moiety effectively initiated the intratumoral Fenton-like reaction to release a large amount of toxic hydroxyl radicals (•OH), which further induced tumor cell apoptosis. Meanwhile, the bonded Pt-N4 moiety could also enhance the Fenton-like activity of the Fe-N3 moiety up to 128.8% by modulating the 3d electronic orbitals of isolated Fe-N3 sites. In addition, the existence of amorphous carbon revealed high photothermal conversion efficiency when exposed to an 808 nm laser, which synergistically achieved an effective oncotherapy outcome. Therefore, the as-obtained (Fe, Pt)SA-N-C-FA-PEG has promising potential in the bio-nanomedicine field for inhibiting tumor cell growth in vitro and in vivo.

Synergistic combination: Promising nanoplatform W‐POM NCs@ HKUST‐1 for photothermal and chemodynamic reinforced anti‐tumor therapy

Chemodynamic therapy (CDT) uses the conversion of H2O2 to ·OH triggered by Fenton‐like reactions to treat tumors, but the treatment is not complete due to insufficient intracellular H2O2 content. Photothermal therapy (PTT) uses photothermal materials for photothermal conversion to kill tumors, but it is limited by the extent of exogenous light transmission and cannot achieve satisfactory therapeutic effects. Therefore, designing a composite nanomaterial that amplifies CDT and couples it with PTT for tumor treatment is a major challenge. Herein, we designed a W‐POM NCs@HKUST‐1 nanoplatform that combines PTT and CDT and has better targeting properties. It shows high stability and photothermal conversion efficiency under the irradiation of near‐infrared light and efficiently catalyzes the generation of intracellular hydroxyl radicals, this composite material exhibits higher lethality than single therapeutic strategies. This study expands the application area of POM@MOF composite nanomaterials and provides a promising means of enhanced tumor therapy.

Multifunctional MoS2 composite nanomaterials for drug delivery and synergistic photothermal therapy in cancer treatment

Due to its excellent photothermal performance, MoS2 is more and more widely used in cancer treatment. In this study, a novel MoS2 composite nanosheets material with lamellar structure and good water solubility (BBPL-MoS2-LP) was synthesized, which had high photothermal conversion efficiency and good biocompatibility. The drug loading efficiency of doxorubicin (DOX) on the composite nanosheets reached 34.43%. Compared with the drug release rate of 15% at pH 7.0, the release degree of DOX was higher at a slightly acidic environment of pH 5.5, reaching 30%. Under the irradiation of near infrared laser (NIR), the drug release was significantly enhanced, indicating that the composite material can be used as a dual response system. The release of DOX would be controlled by pH and near infrared laser (NIR) irradiation. It was also found that BBPL-MoS2-LP could effectively penetrate cell membrane under the endocytosis mechanism mediated by biotin receptor and release drugs in HeLa cells. Cytotoxicity and apoptosis experiments showed that BBPL-MoS2-LP had better ability to kill HeLa cells than single drug or photothermal irradiation alone. The as-prepared multifunctional composite nanosheets in this study has great potential in effective drug delivery and photothermal chemotherapy for tumor treatment.

Carbon spheres with high photothermal conversion efficiency for photothermal therapy of tumor

Development of high-performance photothermal agent plays a decisive role in photothermal therapy of tumor. Herein, carbon spheres are rapidly synthesized by pyrolysis of pyrogallol-formaldehyde spheres at 400–1000 °C under nitrogen atmosphere. As-prepared carbon spheres exhibit strong absorption in near-infrared region and good photothermal effect. The results reveal that the photothermal conversion efficiency of carbon spheres has a tight association with carbon defects caused by pyrolysis. The carbon defects serve as the nonradiative recombination centers of the excited electrons to promote photothermal conversion efficiency. Strikingly, carbon spheres after calcination at 700 °C exhibit the photothermal conversion efficiency of 54.2% under 808 nm laser irradiation, which is superior to the reported carbon-based photothermal agents. The prepared carbon spheres have good cell biocompatibility and can ablate the tumor tissues in tumor-bearing mice through the conversion of near-infrared laser energy into thermal energy.

Architecting polyelectrolyte hydrogels with Cu-assisted polydopamine nanoparticles for photothermal antibacterial therapy.

Polydopamine nanoparticles (PDA NPs) are an appealing biomimetic photothermal agent for photothermal antibacterial treatment because of their long-term safety, excellent photostability, accessible manufacturing, and good biodegradability. However, the low photothermal conversion efficiency (PCE) of PDA NPs requires high-power and long-term near-infrared light irradiation, which severely restricts their practical application. In this work, PDA@Cu NPs were fabricated by growing Cu NPs in situ on the surface of PDA and then introduced into a polyelectrolyte hydrogel precursor (cationic polyethyleneimine/anionic pectin, named as CPAP). The formulated photothermal platform possessed a high PCE (55.4%), almost twice as much as pure PDA NPs (30.8%). Moreover, the designed CPAP/PDA@Cu captured and killed some bacteria by electrostatic adsorption, which helped enhance the antibacterial performance. As expected, the formed CPAP/PDA@Cu that combined the advantageous features of PDA@Cu NPs (high PCE) and CPAP matrix (inherent antibacterial activity and preventing NPs aggregation) can efficiently kill bacteria both in vitro and in vivo under the help of near-infrared laser irradiation. Taken together, this study offers a promising strategy for constructing a facile and safe PDA-based photothermal agent for photothermal antibacterial therapy.

Photogenerated reactive oxygen species and hyperthermia by Cu3SnS4 nanoflakes for advanced photocatalytic and photothermal antibacterial therapy

BackgroundThe rapid spread of infectious bacteria has brought great challenges to public health. It is imperative to explore effective and environment-friendly antibacterial modality to defeat antibiotic-resistant bacteria with high biosafety and broad-spectrum antibacterial property.ResultsHerein, biocompatible Cu3SnS4 nanoflakes (NFs) were prepared by a facile and low-cost fabrication procedure. These Cu3SnS4 NFs could be activated by visible light, leading to visible light-mediated photocatalytic generation of a myriad of reactive oxygen species (ROS). Besides, the plasmonic Cu3SnS4 NFs exhibit strong near infrared (NIR) absorption and a high photothermal conversion efficiency of 55.7%. The ROS mediated cellular oxidative damage and the NIR mediated photothermal disruption of bacterial membranes collaboratively contributed to the advanced antibacterial therapy, which has been validated by the efficient eradication of both Gram-negative Escherichia coli and Gram-positive methicillin-resistant Staphylococcus aureus strains in vitro and in vivo. Meanwhile, the exogenous copper ions metabolism from the Cu3SnS4 NFs facilitated the endothelial cell angiogenesis and collagen deposition, thus expediting the wound healing. Importantly, the inherent localized surface plasmon resonance effect of Cu3SnS4 NFs empowered them as an active substrate for surface-enhanced Raman scattering (SERS) imaging and SERS-labeled bacteria detection.ConclusionsThe low cost and biocompatibility together with the solar-driven broad-spectrum photocatalytic/photothermal antibacterial property of Cu3SnS4 NFs make them a candidate for sensitive bacteria detection and effective antibacterial treatment.Graphical

Multifunctional TiO2/C nanosheets derived from 3D metal–organic frameworks for mild-temperature-photothermal-sonodynamic-chemodynamic therapy under photoacoustic image guidance

The sythesis of composite nanosheets with multiple functions remains signifcantly challenging. In this study, we developed multifunctional H-TiO2/C-PEG nanosheets as theranostic agents combining sonodynamic therapy and a low-power-mild-photothermal-enhanced Fenton effect. The two-dimensional H-TiO2/C composite nanosheets were synthesized by reducing metal–organic frameworks (MOF)-derived from H-TiO2/C composite nanoparticles (NPs) by hydrogen. The resulting H-TiO2/C was introduced into polyethylene (PEG) to improve water solubility and increase the size of the particles to allow a higher level of H-TiO2/C accumulation at the tumor site through the enhanced permeability and retention effect. The H-TiO2/C nanosheets had excellent sonodynamic therapy (SDT) effects and could also achieve low-power mild photothermal therapy guided by photoacoustic imaging with high photothermal conversion efficiency (η = 56.2 %). Also, a strong photothermal effect accelerated the rate of the Fenton reaction to enhance the efficacy of chemodynamic therapy (CDT). Importantly, combination therapy can achieve signifcant antitumour efficacy whilst the strong biocompatibility of the particles minimising adverse effects in normal cells. This study provides a promising strategy for the development of novel two-dimensional composite materials that are safe and have multifunctional diagnostic and therapeutic properties.

NIR-activated multi-hit therapeutic Ag2S quantum dot-based hydrogel for healing of bacteria-infected wounds

Hydrogel dressings are highly biocompatible and can maintain a moist wound environment, suggesting constructing an efficient multi-modal antibacterial hydrogel platform is a promising strategy for treating bacterial wound infections. In this work, a composite Ag2S quantum dot/mSiO2 NPs hydrogel (NP hydrogel) with antibacterial ability was constructed by incorporating Ag2S quantum dots (QDs) modified by mesoporous silica (mSiO2) into the network structure of 3-(trimethoxylmethosilyl) propyl methacrylate based on free radical polymerization. The NP hydrogel showed outstanding controllable photothermal and photodynamic characteristics under 808 nm near infrared (NIR) light irradiation, with a photothermal conversion efficiency of 57.3%. Additionally, the release of Ag+ could be controlled by the inherent volume change of the NP hydrogel made of N-isopropylacrylamide (NIPAAm) and acrylamide (AAm) during NIR laser exposure, with the embedded Ag2S QDs working as a reservoir to release Ag+ continuously from the hydrogel matrix to achieve bactericidal activity. The synergetic effects between hyperthermia, radical oxygen species, and Ag+ released under NIR radiation endowed the NP hydrogel with prominent antibacterial properties against Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA), with an inhibition rate of 99.7% and 99.8%, respectively. In vivo wound healing experiments indicated that the NP hydrogel could enhance bacterial clearance, increase collagen coverage area and up-regulate VEGF expression, exhibiting high biocompatibility. Overall, this study proposed an efficient and highly biocompatible multi-modal therapeutic nanohydrogel, opening up a new way for developing broad-spectrum antibacterial wound dressings to treat bacterial wound infections. Statement of significanceBacterial wound infection is still one of the most difficult medical problems. In this work, a stimulating NIR-responsive hydrogel encapsulating functional Ag2S QDs was prepared, which showed high photothermal conversion efficiency (57.3%) and outstanding antibacterial ability under 808 nm NIR laser, killing 99.7% and 99.8% of E. coli and MRSA in 4 min, respectively. During NIR light irradiation, the release rate of Ag+ could be regulated by the intrinsic volume transition of the hydrogel, leading to remarkable antibacterial properties in vitro and in vivo under the combined action of hyperthermia, radical oxygen species and Ag+ released. This study proposed a novel multi-modal therapeutic nanohydrogel, opening up a new way for developing broad-spectrum antibacterial wound dressings to treat bacterial wound infections.

Photodynamic Therapy of Up-Conversion Nanomaterial Doped with Gold Nanoparticles.

Two key concerns exist in contemporary cancer chemotherapy: limited therapeutic efficiency and substantial side effects in patients. In recent years, researchers have been investigating the revolutionary cancer treatment techniques of photodynamic therapy (PDT) and photothermal therapy (PTT) proposed by many scholars. A photothermal treatment of cancer was synthesized using the hydrothermal method which has high photothermal conversion efficiency and can generate reactive oxygen species (ROS) in cells. Photothermal treatment of tumors has a good short-term effect and photodynamic therapy lasts longer. However, both PTT and PDT have their inevitable shortcomings and it is difficult to completely eradicate a tumor using a single mode of treatment. PTT and PDT synergistic treatment not only inherits the advantages of low toxicity and side effects of phototherapy but also enables the two treatment methods to complement each other. It is an effective strategy to improve curative effects and reduce toxic and side effects. Furthermore, gold doped UCNPs have an exceptionally high target recognition for tumor cells. The gold doped UCNPs, in particular, are non-toxic to normal tissues, endowing the as-prepared medications with outstanding therapeutic efficacy and exceptionally low side effects. These findings may encourage the creation of fresh, effective imaging-guided approaches to meet the goal of photothermal cancer therapy.

2D Molybdenum Sulfide‐Based Materials for Photo‐Excited Antibacterial Application

Bacterial infections have seriously threatened human health. The abuse of natural or artificial antibiotics leads to bacterial resistance, so developing new generation of antibacterial agents and treatment methods is urgent. Two-dimensional (2D) molybdenum sulfide (MoS2 ) has good biocompatibility, high specific surface area to facilitate surface modification and drug loading, adjustable energy band gap, and high near-infrared photothermal conversion efficiency (PCE), so it is often used for antibacterial application through its photothermal or photodynamic effects. Herein, this review makes a comprehensive summarization and discussion on the fabrication processes, structural characteristics, antibacterial performance and the corresponding mechanisms of MoS2 -based materials as well as their representative antibacterial applications. In addition, the outlooks on the remaining challenges that should be addressed in the field of MoS2 are also proposed. This article is protected by copyright. All rights reserved.

Versatile Au@Ru nanocomposites for the rapid detection of Salmonella typhimurium and photothermal sterilization

In view of the current public health hazards of food-borne pathogens, it is urgent to develop a rapid detection method with high sensitivity, good specificity and operational convenience, as well as to determine an effective sterilization strategy. Herein, versatile gold-ruthenium nanocomposites modified with antibody (Au@Ru-pAb Ncs) have been constructed for the sensitive detection of Salmonella typhimurium (S. typhimurium) via the lateral flow immunochromatographic assay (LFIA). Au@Ru-pAb Ncs based LFIA exhibited a wide detection range from 2.9 × 106 CFU/mL to 2.9 × 1011 CFU/mL with the limit of detection of 9.8 × 104 CFU/mL for S. typhimurium, and displayed excellent specificity. In addition, Au@Ru-pAb Ncs irradiated with 808 nm (500 mW/cm2) near-infrared light (NIR) had a significant antibacterial effect within only 5 min, attributed to its high photothermal conversion efficiency of 54.14%. Therefore, both sensitive detection of S. typhimurium and effective NIR-triggered photothermal sterilization were achieved by using versatile Au@Ru-pAb Ncs, showing great prospects in the field of pathogen detection and treatment.