Photothermal Properties Research Articles

Leveraging Non-Radiative Transitions in Asphaltenes-Derived Carbon Dots for Cancer Photothermal Therapy.

Cancer photothermal therapy leverages the capability of photothermal agents to convert light to heat for cancer cell ablation and necrosis. However, most conventional photothermal agents (Au, CuS, Pd, mesoporous silica nanoparticles, and indocyanine green dye) either face scalability challenges or photobleached upon prolonged irradiation which jeopardizes practical applications. Here, asphaltenes-derived carbon dots (ACDs, 5nm) are rationally engineered as a low-cost and photostable photothermal agent with negligible in vivo cytotoxicity. The abundant water-solvating functional groups on the ACDs surface endows them with excellent water re-dispersibility that outperforms those of most commercial nanomaterials. Photothermal therapeutic property of the ACDs is mechanistically described by non-radiative transitions of excited electrons at 808nm via internal conversions and vibrational relaxations. Consequently, the ACDs offer cancer photothermal therapy in mice within 15 days post-exposure to one-time near infrared irradiation. This pioneering study showcases the first utilization of asphaltenes-based materials for cancer therapy and is expected to arouse further utilization of such materials in various cancer theranostics.

The efficacy and safety of pH-responsive and photothermal-sensitive multifunctional nanoparticles loaded with cryptotanshinone for the treatment of gastric cancer.

A multifunctional polydopamine/mesoporous silica nanoparticles loaded cryptotanshinone (PDA/MSN@CTS) was synthesized and subjected to investigating its physicochemical properties and anti-gastric cancer (GC) effects. Utilizing network pharmacology and molecular docking techniques, CTS was identified as our final research target. The structural morphology and physicochemical properties of PDA/MSN@CTS were examined. Near-infrared (NIR) laser was employed to evaluate the photothermal properties of the PDA/MSN@CTS, along with pH-responsive and NIR-triggered release assessments. In vitro experiments evaluated the impact of PDA/MSN@CTS on the malignant behavior of AGS gastric cells. A subcutaneous tumor model was further established to evaluate the in vivo safety of PDA/MSN@CTS. Furthermore, the in vivo photothermal efficacy of PDA/MSN@CTS, in addition to its combined effect with photothermal therapy (PTT), was investigated. Uniform and stable PDA/MSN@CTS had been successfully synthesized and demonstrated efficient release under tumor environment and NIR irradiation. Upon increasing NIR laser conditions, in vivo cytotoxicity, apoptosis rate, reactive oxygen species scavenging ability, and suppression of migration and invasion of AGS cells by PDA/MSN@CTS were significantly enhanced. In vivo assessments revealed excellent blood compatibility and biosafety of PDA/MSN@CTS, alongside robust tumor tissue targeting. Combining nanoparticles with PTT facilitated the anti-GC effects of PDA/MSN@CTS. Compared to free drugs, PDA/MSN@CTS exhibits higher selectivity towards cancer cells, demonstrating effective anticancer activity and biocompatibility both in vitro and in vivo. Furthermore, our nanomaterial possesses excellent photothermal properties, and under NIR conditions, PDA/MSN@CTS exhibits synergistic therapeutic effects.

Eco‐Friendly, Recyclable Supramolecular Inks Incorporating Multi‐Walled Carbon Nanotubes

AbstractIn contemporary society, with its emphasis on environmental stewardship, the development of “green” (eco‐friendly) inks is of paramount importance. These inks are utilized across a broad spectrum of applications, ranging from the printing of packaging material to the 3D printing of functional components. This study explores the synthesis of eco‐friendly, biodegradable supramolecular polymer materials predicated on ureido‐pyrimidinone (UPy). The subsequent formulation of these materials into functional inks is achieved by the incorporation of multi‐walled carbon nanotubes (MWCNTs). These resultant inks exhibit outstanding photothermal conversion properties, robust electrical conductivity, intrinsic self‐repair capabilities, and superior writability. Moreover, this research demonstrates the recyclability of MWCNTs within the ink matrix, exhibiting a recovery efficiency of ≈90%. Such a high recovery rate offers a novel perspective on the sustainable reuse of conductive fillers in polymer‐based inks.

Bi2Se3/PAAS Hydrogels with Photothermal and Antioxidant Properties for Bacterial Infection Wound Therapy by Improving Vascular Function and Regulating Glycolipid Metabolism.

Skin is the largest organ in the human body, and it is also the most important natural barrier. However, some accidents can cause skin damage. Bacterial infections and inflammatory reactions can hinder wound healing. Therefore, eliminating bacterial infections and regulating oxidative stress are essential. The use of antibiotics is no longer sufficient because of bacterial resistance. The development of new nanomaterials provides another way of thinking about bacterial drug resistance. In this study, bismuth selenide is modified with polyethylpyrrolidone to obtain a 2D nanomaterial with negligible toxicity and then added to a sodium polyacrylate hydrogel, which is nontoxic and has strong tissue adhesion and a weak antibacterial effect. To further enhance antibacterial performance, photothermal therapy is a good strategy. Under near-infrared light, Bi2Se3/PAAS shows a strong bactericidal effect. Bi2Se3/PAAS hydrogels also have certain antioxidant effects and are used to remove excess free radicals from wound infections. The effective therapeutic effect of Bi2Se3/PAAS/NIR on methicillin-resistant Staphylococcus aureus (MRSA) infection is further verified in animal models. Transcriptome analysis reveals that the Bi2Se3/PAAS hydrogel improves the function of vascular endothelial cells, regulates glucose and lipid metabolism, and promotes the healing of infected wounds.

Full-spectrum plasmonic semiconductor with stabilized oxygen vacancies enables VOCs purification for durable clean water capture

To mitigate health risks associated with volatile organic compounds (VOCs) in solar-driven water evaporation, we developed Au/WO2.72 material with full-spectrum absorption capabilities and dual photothermal and photocatalytic properties. Injecting hot electrons from Au nanoparticles (NPs) into WO2.72 preserves oxygen vacancies, thus maintaining the plasmonic effect and significantly reducing hot electron relaxation. This leads to enhanced purification of VOCs. The MF-Au/WO2.72 water evaporator, constructed on a melamine–formaldehyde (MF) substrate, demonstrated a water evaporation rate of 1.36 kg m-2 h−1 and stability over 6 h daily for 12 days under one sun irradiation. Importantly, it achieved a 92.9 % removal efficiency for phenol VOCs. Outdoor experiments validated its effectiveness in organic wastewater purification and seawater desalination, highlighting its potential for efficient and clean water production by simultaneously removing VOCs during the evaporation process. This work provides valuable insights into utilizing plasmonic-coupling materials for solar water purification.

CuS hollow nanocages with rough surface to enhanced photothermal property for ultra-sensitive detection of furazolidone metabolites

Signal tracers play a key role in the lateral flow immunoassay (LFIA) for improving sensitivity and signal output capability. Photothermal signal has sparked significant excitement in designing high-performance LFIAs. Herein, CuS hollow nanocages (CuS HNCs) were synthesized for building a dual signal LFIA. CuS HNCs show excellent photothermal conversion efficiency due to their unique morphology and superior localized surface plasmon resonance (LSPR) effect. Meanwhile, the hollow-cage structure endows CuS HNCs with high light absorption and suitable colorimetric property. Furazolidone (FZD) metabolite was used as a model target in the developed LFIA to demonstrate its superior comprehensive performances brought by CuS HNCs. The limit of detection is as low as 0.099 ng mL−1 (colorimetric mode) and 0.075ng mL−1 (photothermal mode), respectively. Furthermore, standard recovery test in honey and shrimp samples was performed and the recovery rates ranged from 86.33 % to 116.71 %. This study not only introduces a new type of nanolabel characterized by an abundance of high-energy hot carriers and pronounced thermal effects, enabling the development of exceptionally sensitive immunosensor platforms but also extends applications of hollow plasmonic photothermal material in the point-of-care (POC) diagnostic field.

Micro-structure design of black ceramic composite surface towards photothermal superhydrophobic anti-icing

Conventional superhydrophobic surfaces have limitations in the melting and icing process in response to ambient temperature. In this study, we fabricated a composite coating using plasma-etched black ceramic as a low layer on the surface of AZ31 magnesium alloy, and loaded-polydimethylsiloxane nanoparticles (PDMS NPs) as a top layer to achieve a photothermal and superhydrophobic anti-icing. The absorbance and forbidden bandwidth of the ceramic layer exhibit the excellent photothermal properties of solid solution (Mg1-XCuXO). The ceramic phase exhibits a bandgap of 3.62 eV and achieves a temperature of up to 69.4 °C, demonstrating desirable light absorption and photothermal properties. The microstructure and polar bonds of Si-O-Si provide excellent superhydrophobic properties, allowing the surface contact angle to reach 156°. The wetting of water droplets on the composite coating’s surface is simulated using molecular dynamics, which is consistent with experimental findings and emphasizes the coating’s exceptional superhydrophobic. Additionally, the transition process between Cassie-Baxter and Wenzel was analyzed by researching the dynamic icing and ice-melting processes. This composite surface converts light energy into heat, melts snow/ice, and uses hydrophobicity to promptly desorb it from the surface, enabling a photothermal active and superhydrophobic passive anti-icing strategy.

Superhydrophobic photothermal evaporator based on MoS2 nanoflowers for efficient solar desalination

Solar desalination is a promising solution to address global water scarcity. In this study, a novel superhydrophobic photothermal evaporator based on MoS2 nanoflowers, known for their excellent photothermal conversion properties, was developed. The evaporator is coated with 1H, 1H, 2H, 2H-Perfluorodecyltriethoxysilane (PFDTES) to create superhydrophobic structures, which are then loaded onto a macroporous non-woven fabric (NWF) to facilitate efficient steam release. The hydrophobic PFDTES coating effectively prevents salt crystallization, ensuring long-term desalination. The developed device demonstrates an exceptional solar steam generation performance of 1.52 kg m−2 h−1 with an evaporation efficiency of up to 87.1 %. This evaporator offers a promising solution to water scarcity challenges due to its high evaporation efficiency, impressive durability, and low-cost.

Chitosan-puerarin composite hydrogel with magnetic enhanced photothermal properties as sustained antimicrobial coatings for beef preservation

The bactericidal properties of traditional food coatings mostly depend on the amount of fungicides present, which reduces the sustainability of food packaging. Herein, we proposed a magnetic field to precisely modulate the near-infrared (NIR) absorption activity to enhance antimicrobial coatings sustainability. Inspired by the typical grinding procedure, the assembly of CP/Fe3O4@TA nanofiber hydrogel was proposed as the coating, applying mechanical force and encouraging the collision of effective molecules of puerarin (PUE), chitosan (CS), and Fe3O4@TA NFs. This hydrogel design offers precise control over the physical and chemical properties, including appearance, viscoelasticity, and rheology. Particularly, significant changes in photothermal performance were observed as a result of magnetic regulation of NIR absorption activity. As a result, the CP/Fe3O4@TA coatings achieve effective bacteria killing performance under NIR irradiation, magnetocaloric effect, boric acid adsorption, and aggregation interference. Finally, the hydrogel coating was applied to the beef surface and serves as an effective barrier against the growth of pathogenic bacteria, thereby preserving the freshness and tenderness of the beef. The finding from this work is expected to open up a new way in active nano hydrogel coating for food preservation.

Enhanced photothermal conversion properties of graphene aerogel surface and its application in oil spill treatment

As an environmentally friendly material, graphene aerogel has been widely studied. The photothermal conversion performance is an important property of graphene aerogel. Graphene aerogels were prepared by hydrothermal reduction method. The factors affecting its surface photothermal conversion properties were explored and graphene aerogels with ideal photothermal conversion properties were obtained. In addition, COMSOL Multiphysics simulation was carried out to further analyze the intrinsic factors affecting the photothermal properties of the materials. The prepared materials were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Raman spectrometry (Raman) to obtain their physicochemical properties. UV–visible-near infrared spectrophotometer and microcomputer-controlled electronic universal testing machine were used to evaluate the light-absorbing capacity and mechanical properties of the materials. The obtained graphene aerogel can be rapidly heated up to higher than 110 °C in 8 s on its surface under simulated sunlight (1000 W·m−2) irradiation. When used for the treatment of oil spill at sea, the prepared graphene aerogel with good photothermal conversion ability can adsorb 105.61 times of its own weight of crude oil and the adsorption rate is as high as 10.56 g·g−1·min−1, which shows a broad application prospect.

A novel multimodal aptasensor for Patulin detection in fruit products based on high-performance RuMOF@hydrogel and versatile pericarp-derived carbonized polymer dots

Patulin (PAT) is a widespread fruit toxin. Trace-level PAT exposure can cause serious harm to human health. Herein, a multimodal PAT aptasensor was designed based on Ru(bpy)32+-based metal organic framework composited hydrogel (RuMOF@hydrogel) and versatile banana peel-derived carbonized polymer dots (BPPDs). RuMOF@hydrogel modified magnetic-electrode exhibited excellent anodic and cathodic electrochemiluminescence (ECL) emission and stability. Meanwhile, the BPPDs could enhance anodic ECL of RuMOF@hydrogel, and also show excellent fluorescence (FL) and photothermal (PT) properties. With the aid of PAT-triggered hybridization chain reaction and magnetic separation, ECL, FL, and PT responses could be recorded concurrently. The detection limit can reach as low as 0.25 fg mL−1. The ratiometric ECL quantitation ensured the sensitivity and accuracy of this assay. And visual FL and portable PT modes contributed to the utility. Furthermore, this aptasensor demonstrated better performances than HPLC in fruit products and the protocol can be extended to determine various contaminants in foods.

Enhancing Root Canal Therapy with NIR-II Semiconducting Polymer AIEgen and Low-Concentration Sodium Hypochlorite Synergy.

Despite significant efforts to eliminate bacterial biofilm within root canals, achieving effective disinfection remains challenging due to the complex anatomy and limitations of disinfectants. In this study, a second near-infrared (NIR-II) semiconducting polymer with aggregation-induced emission (AIE) properties, named PIDT-TBT, is deliberately designed and synthesized. This proposes an AIE luminogen-based sterilization strategy in synergy with a low concentration of sodium hypochlorite (NaClO). Water-dispersible PIDT-TBT nanoparticles (NPs) are prepared, demonstrating good biocompatibility, as well as photothermal and photodynamic properties. Subsequent antibacterial tests show that PIDT-TBT NPs exhibit excellent bactericidal effects against three bacterial strains: Staphylococcus aureus, Streptococcus mutans, and Enterococcus faecalis, upon 808nm laser irradiation. In synergy with a low concentration of NaClO (0.5%) solution, PIDT-TBT NPs significantly improves the outcome of root canal treatment under 808nm laser irradiation in a human extracted tooth root canal infection model. Additionally, it is found that PIDT-TBT NPs combine with a low concentration of NaClO solution could safely dissolve dentin debris and further increase the efficiency of root canal preparation by altering the elemental composition of the inner root canal wall.

Iron-copper bimetallic photo-Fenton system promoted photothermal-hydrogen peroxide production for efficient low-temperature wastewater treatment

Enhancing the velocity of the oxidation–reduction cycle is crucial for improving the catalytic efficiency of Fenton processes. Therefore, the development of an effective strategy for wastewater degradation at low temperatures is essential. In this context, we present the preparation of an NH2-MIL-88B (Fe)/CuInS2 S-scheme heterojunction. Specifically, CuInS2 nanoparticles are introduced onto the Ferro-organic skeleton, resulting in the exposure of a significant number of active surface sites. Furthermore, NH2-MIL-88B (Fe)/CuInS2 demonstrates an extended photoresponse into the long-wavelength region, which contributes to its excellent photothermal properties. Notably, the degradation rate of tetracycline in low-temperature aqueous environments reaches as high as 99.7 %, several times higher than that of the original sample. Additionally, the hydrogen production of NH2-MIL-88B (Fe)/CuInS2 is 2.23 times that of single NH2-MIL-88B (Fe) and 3.46 times that of single CuInS2. Moreover, the system exhibits good H2O2 evolution performance, forming an efficient photo-Fenton system. The charge transfer process in S-scheme heterojunction is confirmed using in-situ X-ray photoelectron spectroscopy and electron paramagnetic resonance. Both transient photoluminescence and photo electrochemical tests further validate the enhanced photoelectrochemical properties of the NH2-MIL-88B (Fe)/CuInS2 S-scheme heterojunction. The exceptional performance of this system can be attributed to the synergistic effects of the S-scheme heterojunction and the bimetallic codoped photo-Fenton system. This research presents a novel approach for the breakdown of low-temperature wastewater using an improved photocatalytic Fenton system.

BiVO4 Film Coupling with CoAl2O4 Nanoparticles for Photoelectrochemical Water Splitting Utilizing Broad Solar Spectrum through p-n Heterojunction, Photothermal, and Cocatalytic Synergism.

Water oxidation is an endothermic and kinetics-sluggish reaction; the research of photoanodes with photothermal and cocatalytic properties is of great significance. Herein, BiVO4/CoAl2O4 film photoanodes were studied for solar water splitting through coupling spinel p-type CoAl2O4 nanoparticles on n-type BiVO4 films. Compared to the BiVO4 photoanode, better performance was observed on the BiVO4/CoAl2O4 photoanode during water oxidation. A photocurrent of 3.47 mA/cm2 was produced on the BiVO4/CoAl2O4 photoanode at 1.23 V vs RHE, which is two-fold to the BiVO4 photoanode (1.70 mA/cm2). Additionally, the BiVO4/CoAl2O4 photoanodes showed an acceptable stability for water oxidation. The BiVO4/CoAl2O4 photoanode being of higher water oxidation performance could be attributed to the presence of p-n heterojunction, cocatalytic, and photothermal effects. In specific, under the excitation of λ < 520 nm light, the holes produced in/on BiVO4 can be transferred to CoAl2O4 owing to the p-n heterojunctions of BiVO4/CoAl2O4. Meanwhile, the temperature on the BiVO4/CoAl2O4 photoanode rises quickly up to ∼53 °C under AM 1.5 G irradiation due to the photothermal property of CoAl2O4 through capturing the 520 < λ < 720 nm light. The temperature rising on the BiVO4/CoAl2O4 photoanode improves the cocatalytic activity of CoAl2O4 and modifies the wettability of BiVO4/CoAl2O4 for effective water oxidation.

Cocktail Approach with Polyserotonin Nanoparticles and Peptides for Treatment of Streptococcus mutans.

Dental plaque, formed by a Streptococcus mutans biofilm, is a major contributor to cavity formation. While antimicrobial strategies exist, the growing risk of antibiotic resistance necessitates alternative therapeutic solutions. Polyserotonin nanoparticles (PSeNPs), recently recognized for their photothermal property and promising biomedical applications, open up a new avenue for antimicrobial use. Here, we introduced a UV-initiated synthetic route for PSeNPs with improved yield. Using these PSeNPs, a cocktail treatment to reduce the viability of this cavity-causing bacteria was developed. This cocktail comprises an S. mutans-targeting antimicrobial peptide (GH12), an intraspecies competence-stimulating peptide that triggers altruistic cell death in S. mutans, and laser-activated heating of PSeNPs. The "peptide + PSeNP + laser" combination effectively inhibits S. mutans growth in both planktonic and biofilm states. Moreover, the cocktail approach remains effective in reducing the viability of S. mutans in a more virulent dual-species biofilm with Candida albicans. Overall, our results reinforce the utility of a multipronged therapeutic strategy to reduce cariogenic bacteria in the complex model oral biofilm.

Adipocyte-Targeted Nanocomplex with Synergistic Photothermal and Pharmacological Effects for Combating Obesity and Related Metabolic Syndromes.

Obesity is a global epidemic which induces a multitude of metabolic disorders. Browning of white adipose tissue (WAT) has emerged as a promising therapeutic strategy for promoting weight loss and improving associated metabolic syndromes in people with obesity. However, current methods of inducing white adipose tissue browning have limited applicability. We developed a nanocomplex pTSL@(P+I), which is a temperature-sensitive liposome (TSL) surface-conjugated with an adipocyte-targeting peptide (p) and loaded with both browning-promoting agents (P) and photosensitizing agents (I). This nanocomplex exhibits adipocyte targeting, as well as synergistic pharmacological and photothermal properties to promote browning. pTSL@(P+I) effectively upregulates UCP1 and COX5B expression by activating the transcription axis of PPARγ/PGC1α and HSF1/PGC1α, thereby promoting white adipose tissue browning and reducing obesity. This novel nanocomplex exhibited a uniform spherical shape, with an average diameter of approximately 200 nm. Additionally, the nanocomplexes exhibited remarkable photothermal properties and biocompatibility. Further, when adipocytes were treated with pTSL@(P+I), their triglyceride content decreased remarkably and intracellular mitochondrial activity increased significantly. When applied to diet-induced obesity (DIO) mice, the nanocomplex exhibited significant efficacy, demonstrating a notable 14.4% reduction in body weight from the initial measurement, a decreased fat/lean mass ratio of 20.8%, and no statistically significant disparities (p > 0.05) in associated side effects when compared to the control group. In summary, implementation of the targeted nanocomplex pTSL@(P+I) to enhance energy expenditure by stimulating white adipose tissue browning offers a promising therapeutic approach for the treatment of obesity and related metabolic syndromes.

Design and development of lignin nanobottles: Toward developing novel multifunctional nanocomposites

The design of lignin nanostructures, which leverages interfacial interactions to enhance colloidal network entanglement, holds promise for expanding their applications in polyvinyl alcohol (PVA) composites. Herein, a novel approach is proposed for fabricating lignin nanobottles (LNBs) using biomass-derived γ-butyrolactone (GBL) to create hollow interiors connected to a single surface opening. The resulting LNBs exhibit uniform sizes of approximately 108 nm with an opening diameter of 34.94 nm. Incorporating LNBs into PVA composites enhances mechanical properties significantly, with a tensile strength of 64.96 MPa and an elongation at break of 611.6 %. Moreover, the nanocomposite films demonstrate notable antibacterial effects, UV protection, and hydrophobicity. Introducing LNBs improves photothermal conversion capacity, achieving a temperature of 62.1 °C in just 150 s. Furthermore, a meticulously designed 3D solar evaporator demonstrates remarkable evaporation performance, achieving a rate of up to 1.89 kg m-2h−1 with an outstanding efficiency of 96.55 %. When exposed to 1 sunlight, the thermoelectric material generates an output voltage of 0.83 V, indicating considerable potential for energy generation. Overall, Incorporating LNBs enhances lignin’s effectiveness in materials and provides a novel approach to augment lignin’s photothermal properties, enabling broader applications in solar-driven evaporation and thermoelectric materials.

Biomimetic Functional Nanocomplexes for Photothermal Cancer Chemoimmunotheranostics

This study presents a novel multimodal cancer theranostic platform developed using tumor cell‐coated biomimetic carbon nanohorn (CNH) complexes that encapsulate the anticancer drug paclitaxel (PTX). This platform combines photothermal therapy, chemotherapy, and immunotherapy to fight against malignant colorectal cancer. These engineered nanocomplexes are designed to deliver sufficient PTX molecules into a targeted solid tumor in a light‐controllable manner while inducing significant photothermal and antitumor immune responses. The outstanding photothermal conversion property of the CNHs under near‐infrared light enables effective cancer cell ablation and awakening of cytotoxic immune responses. Tumor cell membrane‐coated CNHs show improved water dispersibility, immune evasion, and targeting capabilities alongside enhanced immune activation against tumors. The efficacy of the biomimetic functional CNH nanocomplexes is demonstrated through excellent tumor‐targeting, controlled drug‐releasing behavior, and induction of cancer cell death, contributing to a robust antitumor response. This study provides a promising approach to cancer treatment by integrating multiple therapeutic modalities into a single platform, potentially enhancing treatment efficacy to combat intractable cancer.

Thermoresponsive and Substrate Self-Cycling Nanoenzyme System for Efficient Tumor Therapy.

Cerium oxide (CeO2-x) performs well in photothermal and catalytic properties due to its abundance of oxygen vacancies. Based on this, we designed a thermosensitive therapeutic nanoplatform to achieve continuous circular drug release in tumor. It can solve the limitation caused by insufficient substrate in the process of tumor treatment. Briefly, CeO2-x and camptothecin (CPT) were wrapped in an agarose hydrogel, which could be melted by the photothermal effect of CeO2-x. At the same time, the local temperature increase provided photothermal treatment, which could induce the apoptosis of tumor cell. After that, CPT was released to damage the DNA in tumor cells to realize chemical treatment. In addition, CPT could active nicotinamide adenine dinucleotide oxidase to react with O2 to increase the intracellular H2O2. After that, the exposed CeO2-x could catalyze H2O2 to generate cytotoxic reactive oxygen species for chemodynamic therapy. More importantly, CeO2-x could catalyze H2O2 to produce O2, which could combine with the catalytic action of CPT to construct a substrate self-cycling nanoenzyme system. Overall, this self-cycling nanoplatform released hypoxia in the tumor microenvironment and built a multimode tumor treatment, which achieved an ideal antitumor affect.

Melanin as a Photothermal Agent in Antimicrobial Systems.

Bacterial infection is one of the most problematic issues for human health and the resistance of bacteria to traditional antibiotics is a matter of huge concern. Therefore, research is focusing on the development of new strategies to efficiently kill these microorganisms. Recently, melanin is starting to be investigated for this purpose. Indeed, this very versatile material presents outstanding photothermal properties, already studied for photothermal therapy, which can be very useful for the light-induced eradication of bacteria. In this review, we present antibacterial melanin applications based on the photothermal effect, focusing both on the single action of melanin and on its combination with other antibacterial systems. Melanin, also thanks to its biocompatibility and ease of functionalization, has been demonstrated to be easily applicable as an antimicrobial agent, especially for the treatment of local infections.