Photothermal Conversion Effect Research Articles

Photothermal-boosted effect of binary Cu[sbnd]Fe bimetallic magnetic MOF heterojunction for high-performance photo-Fenton degradation of organic pollutants

Overcoming the relatively low catalytic activity and strict acid pH condition of common photo-Fenton reaction is the key to alleviate the serious global burden caused by common organic pollutants. Herein, a binary homologous bimetallic heterojunction of magnetic CuFe2O4@MIL-100(Fe, Cu) metal-organic frameworks (MCuFe MOF) with photothermal-boosted photo-Fenton activity is constructed as an ideal practical photo-Fenton catalyst for the degradation of organic pollutants. Through an in-situ derivation strategy, the formed homologous bimetallic heterojunction with binary redox couples can simultaneously improve the visible light harvesting capacity and expedite the separation and transfer of photogenerated electrons/holes pairs, leading to the continuous and rapid circulation of both FeIII/FeII and CuII/CuI redox couples. Notably, the heterojunction shows intrinsic photo-thermal conversion effect, which is found to be beneficial to boost the photo-Fenton activity. Impressively, MCuFe MOF shows remarkable catalytic performance towards the degradation of various organic pollutants by comprehensively increasing H2O2 decomposition efficiency and decreasing the required dosage of MCuFe MOF (0.05 g L−1) with a wide pH range (3.0–10.0). As such, a photo-Fenton catalyst consisting of binary homologous bimetallic heterojunction is first disclosed, as well as its photothermal-enhanced effect, which is expected to drive great advance in the degradation of organic pollutants for practical applications.

Tumor Microenvironment-Responsive Reagent DFS@HKUST-1 for Photoacoustic Imaging-Guided Multimethod Therapy.

Although multimethod therapy has shown great promise for effective cancer treatment, it is still a great challenge to develop simple and effective strategies to construct multifunctional therapeutic reagents. According to the characteristics of the tumor microenvironment, such as a mild acidic environment and overexpression of H2O2, an intelligent therapeutic reagent with photoacoustic (PA) imaging-guided photothermal therapy, chemodynamic therapy, and in situ chemotherapy was constructed by simply loading disulfiram (DSF) in a Cu-based porous metal-organic framework (HKUST-1). The resultant material DFS@HKUST-1 shows near-infrared adsorption around 600-900 nm and effective photoacoustic imaging properties and photothermal conversion efficiency upon 808 nm irradiation. Besides, after DFS@HKUST-1 is enriched in the tumor, the acidic environment of the tumor will slowly trigger the decomposition of HKUST-1, leading to the release of Cu2+ ions to react with DSF and endogenous H2O2 to generate the Cu/DSF complex (CuET) and cytotoxic •OH for chemotherapy and chemodynamic therapy, respectively. Therefore, DFS@HKUST-1 can serve as a promising tumor microenvironment response therapeutic reagent for photoacoustic imaging-guided multimethod therapy.

Highly-toughened biodegradable poly(L-lactic acid) composites with heat resistance and mechanical-damage-healing ability by adding poly(butylene adipate-co-butylene terephthalate) and carbon nanofibers

Biodegradable poly(L-lactic acid) (PLLA) based blend composites with excellent toughness exhibit comprehensive applications and they can be substitute for the common polyolefin and polyester based composites. To date, various strategies have been developed to enhance the toughness of the PLLA based blends or composites. Here, carbon nanofibers (CNFs) incorporated PLLA/poly(butylene adipate-co-butylene terephthalate) (PBAT) blend composites were investigated. The crystallinity of the PLLA matrix were precisely tailored through annealing treatment. Interestingly, CNFs and PBAT particles self-assembled into the “mutton kebab”-like structure during processing. In addition, the annealing treatment facilitated the epitaxial crystallization of PLLA on the surface of CNFs that were not covered by PBAT due to the excellent heterogeneous nucleation effect of CNFs. Consequently, with the addition of 1 wt% CNFs and tailoring the blend composite with the PLLA crystallinity of about 32.6%, the impact strength of the composite was increased by 270% from 10.0 kJ/m2 to 37.0 kJ/m2. The toughening mechanisms were mainly connected with the greatly strengthened interfacial interaction between PLLA matrix and PBAT particles by CNFs through CNFs bridging effect and CNFs inducing PLLA crystallization, facilitating the transfer of stress under the load condition, especially at high PLLA crystallinity. Furthermore, it was found that CNFs exhibited outstanding photothermal conversion effect, which could endow the blend composites with mechanical-damage-healing ability. This work not only reveals the role of crystalline structure in toughening of the PLLA-based blend composites but also paves an effective way to prepare super-toughened, biodegradable, heat resistant and mechanical-damage-healing PLLA-based composites via tailoring the crystalline structure of the matrix.

A novel intelligent PANI/ PPy@Au@MnO2 yolk − shell nanozyme for MRI-guided ‘triple-mode’ synergistic targeted anti-tumor therapy

The preparation and construction of novel nanostructures as targeting theranostic is of great significance for diagnosis and treatment of tumor. Herein, a novel PANI/PPy@Au@MnO2 (PPAuMns) yolk-shell enzymatic theranostic agent was fabricated firstly via in situ deposition of Au nanoparticles (Au NPs) and reduction of KMnO4 on the surface of PANI/PPy nanocomposites. In addition to high biocompatible and biodegraded performance, PPAuMns possessed amazing tumor microenvironment (TME)-responsive O2 generation capacity, magnetic resonance imaging (MRI) property, enzymatic activity and excellent photothermal conversion effect. Chemotherapeutics doxorubicin and folic acid (FA) were further loaded and decorated on it for targeted tumor therapy. Experiments in vitro and in vivo indicated that DOX-loaded PPAuMns@FA demonstrated excellent synergistic anti-tumor effect combining chemotherapy (CT), chemo-dynamic therapy (CDT) and photothermal therapy (PTT). This work offers a paradigm to design and construct tumor diagnosis and therapy platforms employing TME-responsive synergistic strategy of photothermal ablation, chemo-dynamic and chemotherapy.

Doxorubicin-Loaded MnO2@Zeolitic Imidazolate Framework-8 Nanoparticles as a Chemophotothermal System for Lung Cancer Therapy.

Doxorubicin-loaded MnO2@zeolitic imidazolate framework-8 (DOX/MnO2@ZIF-8) nanoparticles, a smart multifunctional therapeutic platform, were prepared for the treatment of lung cancer. The morphology, structure, and redox and photothermal properties of MnO2@ZIF-8 were characterized by the corresponding methods. The anticancer drug DOX released from the DOX/MnO2@ZIF-8 nanoparticles was measured. The cell viability of Lewis lung cancer (LLC) cells treated with MnO2@ZIF-8 or DOX/MnO2@ZIF-8 nanoparticles was determined using the cell counting kit-8 (CCK-8) method. The cellular uptake of DOX/MnO2@ZIF-8 nanoparticles into LLC cells was observed using a confocal laser scanning microscope. TUNEL staining was performed to evaluate the in vivo therapeutic efficacy of DOX/MnO2@ZIF-8 nanoparticles. The results showed that the as-prepared MnO2@ZIF-8 nanoparticles had an average particle size of 155.59 ± 13.61 nm and the DOX loading efficiency was 12 wt %. MnO2@ZIF-8 could react with H2O2 to generate O2 and showed a great photothermal conversion effect both in vitro and in vivo. Up to 82% of total DOX could be released from DOX/MnO2@ZIF-8 nanoparticles at pH = 5.0. The CCK-8 assay showed that MnO2@ZIF-8 had low cytotoxicity to LLC cells, while DOX/MnO2@ZIF-8 can significantly reduce the cell viability. DOX/MnO2@ZIF-8 can be accumulated in LLC cells over time. Compared with PBS and DOX/MnO2@ZIF-8 groups, the mice in the DOX/MnO2@ZIF-8 + NIR group had the most apoptotic cells and significantly reduced tumor volume. In conclusion, these findings suggest that the as-prepared MnO2@ZIF-8 nanoparticles with synergetic therapeutic effects by photothermal therapy and improved tumor microenvironment and as a pH-responsive nanocarrier for delivering the nonspecific anticancer drug DOX might be applied in the treatment of lung cancer.

Chitosan/Silver Nanoparticle/Graphene Oxide Nanocomposites with Multi-Drug Release, Antimicrobial, and Photothermal Conversion Functions.

In this work, we designed and fabricated a multifunctional nanocomposite system that consists of chitosan, raspberry-like silver nanoparticles, and graphene oxide. The room temperature atmospheric pressure microplasma (RT-APM) process provides a rapid, facile, and environmentally-friendly method for introducing silver nanoparticles into the composite system. Our composite can achieve a pH controlled single and/or dual drug release. Under pH 7.4 for methyl blue loaded on chitosan, the drug release profile features a burst release during the first 10 h, followed by a more stabilized release of 70–80% after 40–50 h. For fluorescein sodium loaded on graphene oxide, the drug release only reached 45% towards the end of 240 h. When the composite acted as a dual drug release system, the interaction of fluorescein sodium and methyl blue slowed down the methyl blue release rate. Under pH 4, both single and dual drug systems showed a much higher release rate. In addition, our composite system demonstrated strong antibacterial abilities against E. coli and S. aureus, as well as an excellent photothermal conversion effect under irradiation of near infrared lasers. The photothermal conversion efficiency can be controlled by the laser power. These unique functionalities of our nanocomposite point to its potential application in multiple areas, such as multimodal therapeutics in healthcare, water treatment, and anti-microbials, among others.

Ultralight and superelastic fibrous sponges with effective heat preservation and photo-thermal conversion for personal cold protection

Advanced warming materials integrating functions of reducing heat loss and providing extra heat for the body have attracted much attention. In this work, an ultralight and superelastic fibrous sponge serving as novel warmth retention materials was obtained by assembling the fibers contained zirconium carbide nanoparticles (ZrC NPs) into three-dimension (3D) configuration and creating the semi-interpenetrating polymer networks (semi-IPNs) within fibers via humidity-induced electrospinning and the thermal crosslinking technology. The resulting fibrous sponge (PCFS-12) exhibits high heat preservation ability (~25.2 mW m−1 K−1) and effective photo-thermal conversion performance that could improve the temperature of PCFS-12 to 70.3 °C under the sunlight irradiation. Moreover, the PCFS-12 showed a low density of 2.8 mg cm−3, low-temperature superelasticity with minor plastic deformation after 1000 compression, and good hydrophobic property (WCA = 132°). This work provides a novel approach to develop high-performance warmth retention materials for personal cold protection.

Intraocular Lens with Mussel-Inspired Coating for Preventing Posterior Capsule Opacification via Photothermal Effect.

Phacoemulsification with implantation of intraocular lens (IOLs) has been widely applied as a standard treatment for cataract, which is the leading cause of vision impairment. However, it still remains a critical challenge to prevent posterior capsule opacification (PCO) in terms of postoperative visual quality. Herein, we report IOLs with mussel-inspired coatings for inhibiting lens epithelial cells and then preventing PCO through photothermal conversion effect. The mussel-inspired coatings are deposited on the nonoptical surface areas of IOLs, endowing the modified IOLs with efficient photothermal conversion property. The temperature can be facilely raised to 50-60 °C for the photothermal IOLs (PT-IOLs) by near-infrared (NIR) laser irradiation at a safe intensity of 0.3 W/cm2. These PT-IOLs display high capability of inhibiting lens epithelial cells (LECs) in vitro. Therefore, under routine NIR laser irradiation, New Zealand white rabbits implanted with the PT-IOLs demonstrate significantly lower evaluation of PCO (EPCO) scores than the control groups. The overall results indicate that our PT-IOLs provide a promising choice for the clinical prevention of PCO, thus opening a way to maintain the postoperative visual qualities for cataract patients.

“Stealth” dendrimers with encapsulation of indocyanine green for photothermal and photodynamic therapy of cancer

Poly(amido amine) dendrimers and indocyanine green have inevitable interaction with proteins and cells, which induces biological toxicity and reduces therapeutic efficacy in vivo. To overcome these shortcomings, a new drug delivery system G5MEK7C(n)-ICG with a “stealth” layer was prepared. The surface of G5MEK7C(n)-ICG was modified with double-layer super hydrophilic zwitterionic materials. In the “stealth” double-layer structure, the outer layer was consisted of zwitterionic Glu-Lys-Glu-Lys-Glu-Lys-Cys (EK7) peptide, and the inner layer was composed of amino and carboxyl groups with a ratio of 1:1. DLS results showed that the average hydrodynamic size of G5MEK7C(n)-ICG was about 25–30 nm, and the zeta potential was proven to undergo a slight charge reversal with the increasing pH values of solutions. Furthermore, G5MEK7C(n)-ICG exhibited excellent biocompatibility to red blood cells and proteins resistance. Photothermal and photodynamic experiments demonstrated that G5MEK7C(n)-ICG had a good photothermal conversion effect and generated singlet oxygen (1O2) under laser irradiation. The MTT and hemolysis results showed that the toxicity of G5 PAMAM was significantly reduced after modification double-layer structure. Cytotoxicity studies and flow cytometry showed G5MEK7C(70)-ICG under laser irradiation had a good effect on killing A549 cells. More importantly, the tumor inhibition rate of mice treated with G5MEK7C(70)-ICG (under laser irradiation) was 78.2% in vivo, which was higher than that of mice treated with free ICG. Compared with free ICG, G5MEK7C(70)-ICG caused less damage to the liver according to the enzyme activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Therefore, dendrimers modified with a zwitterionic double layer will be a promising candidate as a drug delivery system.

Enhanced Photocatalytic CO2 Reduction with Photothermal Effect by Cooperative Effect of Oxygen Vacancy and Au Cocatalyst.

CO2 conversion into chemical fuels is a sustainable approach to the concurrent mitigation of the energy crisis and the greenhouse effect. It is still urgently desirable but quite challenging to explore a promising catalyst for CO2 photoreduction due to the severity in the fast recombination of electron holes and the deficiency of active sites, which have a tremendous influence on the catalytic behavior. In this regard, mesoporous TiO2 nanospheres containing oxygen vacancies (OVs) and metallic Au nanoparticles (NPs) were successfully prepared and showed markedly enhanced CO2 reduction activity and CH4 selectivity by the simple combination of photocatalysis with the simultaneous photothermal effect under full-spectrum irradiation. The dual introduction of OVs and a Au/TiO2 Schottky junction can not only serve as an electron sink to significantly improve the charge separation/transfer efficiency but also show effective photothermal conversion to raise the local temperature of the catalyst, thus resulting in an enhanced shuttle of electrons and desorption of products. This study not only offers new insights into the integrated tuning of charge recombination processes but also demonstrates that the photothermocatalysis has great potential in CO2 reduction.

Visible-light responsive PDI/rGO composite film for the photothermal catalytic degradation of antibiotic wastewater and interfacial water evaporation

A visible-light responsive self-assembled perylenetetracarboxylic diimide (PDI)/reduced graphene oxide (rGO) composite film was obtained and showed excellent photocatalytic performance and efficient interfacial steam generation. The degree of π-π interactions between Perylenetetracarboxylic diimide supramolecular nanofibers (nano-PDI) and rGO regulated the energy band structure and redox potential of the composite film to produce h+ and O2− active species. The photothermal conversion of the composite film under visible light irradiation was realized, which was mainly because the above-bandgap electrons and holes of the upper nano-PDI relaxed to the edge of the band and converted the excess energy into heat. The unique energy band structure of rGO also promotes the effective photothermal conversion of the composite film. The composite film degraded 94.31 % (10 mg/L) of ciprofloxacin hydrochloride (CIP) under 0.5 sun visible light irradiation within 120 min. The corresponding interfacial steam generation efficiency via photothermal conversion of the composite film was 10.92 %. Furthermore, the composite film retained its excellent photothermal performance, when used to remove CIP from real water samples, including Yellow River water, Weihe River water, and tap water.

Multifunctional Photothermal Conversion Nanocoatings Toward Highly Efficient and Safe High-Viscosity Oil Cleanup Absorption

Efficient and safe cleanup for the high-viscosity heavy oil spill has been a worldwide challenge due to its sluggish flowability, while classic absorption methods by electric/solar heating are seriously limited by low efficiency and high fire hazards during heating of highly flammable oil. Facing this dilemma, we reported a novel flame-retardant photothermal conversion nanocoating to endow commercial foams with highly efficient and safe heavy oil cleanup absorption. This multifunctional nanocoating consisting of nano-Fe3O4 and reduced graphene oxide (rGO) that both showed photothermal conversion ability and non-flammable nature can be firmly deposited on the polymer foam skeletons via facile coprecipitation and dip-coating processes. The composite foam showed a tough morphology with high hydrophobicity and low density, thus leading to selective high absorption for various oils and organic solvents. Due to the double photothermal conversion effects of nano-Fe3O4 and rGO, the temperature of the foam can be rapidly heated at a rate of ∼103.5 °C/min (the fastest rate ever) under 1 sun irradiation. Consequently, the foam with a high absorption capacity of 75.1 times its weight demonstrated a rapid absorption rate of 9000 g m-2 min-1 for large-viscosity oil under 1 sun irradiation, which was 3 times faster than previously reported. Furthermore, benefitting from high flame retardancy, elasticity, and magnetism, the foam can be safely and repeatedly used for magnetically controllable oil cleanup absorption, which effectively avoids oil spill hazards.

Photogated proton conductivity of ZIF-8 membranes co-modified with graphene quantum dots and polystyrene sulfonate

Smart proton conductive metal-organic framework (MOF) membranes with dynamic remote control over proton conduction show high potential for use in advanced applications, such as sensors and bioprocesses. Here, we report a photoswitchable proton conductive ZIF-8 membrane by coencapsulating polystyrene sulfonate and graphene quantum dots into a ZIF-8 matrix (GQDs-PSS@ZIF-8) via a solid-confined conversion process. The proton conductivity of the GQDs-PSS@ZIF-8 membrane is 6.3 times higher than that of pristine ZIF-8 and can be reversibly switched by light due to photoluminescence quenching and the photothermal conversion effect, which converts light into heat. The local increase in temperature allows water molecules to escape from the porous channels, which cuts off the proton transport pathways and results in a decrease in proton conductivity. The proton conductivity is restored when the light is off owing to regaining water molecules, which act as proton carriers, from the surroundings. The GQDs-PSS@ZIF-8 membrane responds efficiently to light and exhibits an ON/OFF ratio of 12.8. This photogated proton conduction in MOFs has potential for the development and application of MOF-based protonic solids in advanced photoelectric devices.

Rational Design of All-Organic Nanoplatform for Highly Efficient MR/NIR-II Imaging-Guided Cancer Phototheranostics.

Organic theranostic nanomedicine has precision multimodel imaging capability and concurrent therapeutics under noninvasive imaging guidance. However, the rational design of desirable multifunctional organic theranostics for cancer remains challenging. Rational engineering of organic semiconducting nanomaterials has revealed great potential for cancer theranostics largely owing to their intrinsic diversified biophotonics, easy fabrication of multimodel imaging platform, and desirable biocompatibility. Herein, a novel all-organic nanotheranostic platform (TPATQ-PNP NPs) is developed by exploiting the self-assembly of a semiconducting small molecule (TPATQ) and a new synthetic high-density nitroxide radical-based amphiphilic polymer (PNP). The nitroxide radicals act as metal-free magnetic resonance imaging agent through shortened longitudinal relaxation times, and the semiconducting molecules enable ultralow background second near-infrared (NIR-II, 1000-1700nm) fluorescence imaging. The as-prepared TPATQ-PNP NPs can light up whole blood vessels of mice and show precision tumor-locating ability with synergistic (MR/NIR-II) imaging modalities. The semiconducting molecules also undergo highly effective photothermal conversion in the NIR region for cancer photothermal therapy guided by complementary tumor diagnosis. The designed multifunctional organic semiconducting self-assembly provides new insights into the development of a new platform for cancer theranostics.

High-Performance Laminated Fabric with Enhanced Photothermal Conversion and Joule Heating Effect for Personal Thermal Management.

Multifunctional wearable heaters have attracted much attention owing to their efficient application in personal thermal management. Inspired by the polar bear's thermal management, a laminated fabric with enhanced photothermal conversion, mid-infrared reflection, thermal insulation, and electrical heating performance was developed in this work, which was made of CNT/cellulose aerogel layers, cotton fabrics, and copper nanowire (CuNW)-based conductive network (CNN) layers. The CNN layer made up of highly conductive CuNWs not only exhibits better conductivity to realize the Joule heating effect but also possesses a human mid-infrared reflection property. Moreover, the other side of the cotton fabric was laminated with CNT/cellulose aerogel, which enables the fabric to have a good photothermal conversion ability and thermal insulation performance. The temperature of the laminated fabric could reach to 70 °C within 80 s under 1.8 V; it requires more than 500 s to return to room temperature (28.7 °C). When the light intensity was adjusted to 1000 W/m2, the temperature of the laminated fabric was about 74.0 °C after lighting for 280 s. Our work provides a new approach to improving the performance and energy-saving of personal thermal management fabrics.

Thermally and light‐triggered reconfigurable shape memory polydopamine/epoxy composite with self‐healing and recyclable ability

AbstractShape memory epoxy with self‐healing ability has received much more academia and industry attention. In this work, 4‐aminophenyl disulfide containing disulfide bonds was used to replace the traditional epoxy resin‐curing agent, and the waterborne epoxy resin (sWEP) was composited with the polydopamine (PDA) nanoparticles with photothermal conversion effect through the melt mixing and hot‐press molding. As revealed, the addition of 1 wt% PDA increases the tensile strength of sWEP from 36.1 to 50.3 MPa. Specifically, the shape memory properties of the PDA/sWEP composite as manifested by a ca. 97.4% shape memory fixing ratio and ca. 67.8% shape memory recovery ratio. Moreover, the PDA/sWEP composite had the temperature‐dependent thermosetting and thermoplastic conversion capabilities, which can be programmed to a new permanent shape via a photothermal‐induced plasticity process.

Erbium-doped tungsten selenide nanosheets with near-infrared II emission and photothermal conversion

Two-dimensional transition metal dichalcogenides (2D TMDs) have drawn considerable attention due to their promising applications in biomedical and optoelectronic areas. However, the emission of 2D TMDs materials and devices is mostly limited from visible to the edge of near-infrared (NIR), which restricts their wide applications. Herein, we develop Er doped WSe2 nanosheets through cation exchange and ultrasonication-assisted liquid-phase exfoliation. Thanks to the Er ions, the luminescence of 2D nanosheets can be extended to NIR II window. The emission at NIR II range can effectively penetrate several centimeters thick biological tissue. Furthermore, a series of photothermal experiments is also performed with 808 nm laser. The photothermal conversion efficiency of as-produced nanosheets is determined to be as high as 35.2%, which is greatly higher than many previous reports. It suggests that as-prepared nanosheets combining NIR II emission and highly effective photothermal conversion property may be promising as a bifunctional agent for bioimaging and photothermal therapy.

Self-Assembled Au Nanoparticle Arrays for Precise Metabolic Assay of Cerebrospinal Fluid.

Precise and rapid monitoring of metabolites in biofluids is a desirable but unmet goal for disease diagnosis and management. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) exhibits advantages in metabolite analysis. However, the low accuracy in quantification of the technique limits its transformation to clinical usage. We report herein the use of Au nanoparticle arrays self-assembled at liquid-liquid interfaces for mass spectrometry (MS)-based quantitative biofluids metabolic profiling. The two-dimensional arrays feature uniformly and closely packed Au nanoparticles with 3 nm interparticle gaps. The experimental study and theoretical simulation show that the arrays exhibit high photothermal conversion and heat confinement effects, which enhance the laser desorption/ionization efficacy. With the nanoscale roughness, the AuNP arrays as laser desorption/ionization substrates can interrupt the coffee-ring effect during droplet evaporation. Therefore, high reproducibility (RSD <5%) is obtained, enabling accurate quantitative analysis of diverse metabolites from 1 μL of biofluids in seconds. By quantifying glucose in the cerebrospinal fluid (CSF), it allows us to identify patients with brain infection and rapidly evaluate the clinical therapy response. Consequently, the method shows potential in advanced metabolite analysis and biomedical diagnostics.

Upconversion nanoparticles modified by Cu2S for photothermal therapy along with real-time optical thermometry.

Highly effective photothermal conversion performance coupled with high resolution temperature detection in real time is urgently needed for photothermal therapy (PTT). Herein, ultra-small Cu2S nanoparticles (NPs) were designed to absorb on the surface of NaScF4: Yb3+/Er3+/Mn2+@NaScF4@SiO2 NPs to form a central-satellite system, in which the Cu2S NPs play the role of providing significant light-to-heat conversion ability and the Er3+ ions in the NaScF4: Yb3+/Er3+/Mn2+ cores act as a thermometric probe based on the fluorescence intensity ratio (FIR) technology operating in the biological windows. A wavelength of 915 nm is used instead of the conventional 980 nm excitation wavelength to eliminate the laser induced overheating effect for the bio-tissues, by which Yb3+ can also be effectively excited. The temperature resolution of the FIR-based optical thermometer is determined to be better than 0.08 K over the biophysical temperature range with a minimal value of 0.06 K at 298 K, perfectly satisfying the requirements of biomedicine. Under the radiation of 915 nm light, the Cu2S NPs exhibit remarkable light-to-heat conversion capacity, which is proved by photothermal ablation testing of E. coli. The results reveal the enormous potential of the present NPs for PTT integrated with real-time temperature sensing with high resolution.

Cell membrane coated smart two-dimensional supraparticle for in vivo homotypic cancer targeting and enhanced combinational theranostics.

Development of intelligent and multifunctional nanoparticle for the diagnosis and treatment of cancer has drawn great attention recently. In this work, we design a smart two-dimensional (2D) supraparticle for tumor targeted magnetic resonance imaging (MRI)/photothermal imaging (PTI) and chemo/photothermal therapy (PTT).Methods: The nanoparticle consists of a manganese dioxide (MnO2) nanosheet coated gold nanorod (GNR) core (loading with chemotherapeutics doxorubicin (DOX)), and cancer cell membrane shell (denoted as CM-DOX-GMNPs). Decoration of cell membrane endows the nanoparticle with greatly improved colloidal stability and homotypic cancer cell targeting ability. Once the nanoparticles enter tumor cells, MnO2 nanosheets can be etched to Mn2+ by glutathione (GSH) and acidic hydrogen peroxide (H2O2) in the cytosol, leading to the release of DOX. Meanwhile, stimuli dependent releasing of Mn2+ can act as MRI contrast agent for tumor diagnosis. Illumination with near-infrared (NIR) light, photothermal conversion effect of GNRs can be activated for synergistic cancer therapy.Results: In vivo results illustrate that the CM-DOX-GMNPs display tumor specific MRI/PTI ability and excellent inhibition effect on tumor growth.Conclusion: This bioinspired nanoparticle presents an effective and intelligent approach for tumor imaging and therapy, affording valuable guidance for the rational design of robust theranostics nanoplatform.