NIR Photothermal Therapy Research Articles

Novel two-dimensional FeB nanosheets for photoacoustic imaging-guided NIR-photothermal therapy

The development of biosafe near infrared (NIR)-photothermal nanomaterials is meaningful for tumor-targeted photothermal therapy and photoacoustic imaging for high-performance theranostics, but still challenging. Herein, we propose a new ultrasound-assisted chemical etching method based on the Fenton reaction to synthesize a novel kind of two-dimensional iron boride nanosheets (FBN) as NIR-photothermal nanomaterials. The developed FBN theranostic agent exhibits high NIR adsorption and NIR-photothermal conversion efficiencies, realizing biosafe and high efficacy of photoacoustic imaging-guided tumor-targeted NIR-photothermal therapy of tumor mice.

Cationic conjugated polymer coupled non-conjugated segments for dually enhanced NIR-II fluorescence and lower-temperature photothermal-gas therapy

The lack of a simple design strategy to obtain ideal conjugated polymers (CPs) with high absorbance and fluorescence (FL) in the near-infrared-II (NIR-II; 1000–1700 nm) region still hampers the success of NIR-II light-triggered phototheranostics. Herein, novel phototheranostic nanoparticles (PPN-NO NPs) were successfully prepared by coloading a cationic NIR-II CPs (PBC-co-PBF-NMe3) and a NO donor (S-nitroso-N-acetylpenicillamine, SNAP) onto a 1:1 mixture of DSPE-PEG5000 and dimyristoylphosphatidylcholine (DMPC) for NIR-II FL and NIR-II photoacoustic (PA) imaging-guided low-temperature NIR-II photothermal therapy (PTT) and gas combination therapy for cancer treatment. A precise NIR-II FL dually enhanced design tactic was proposed herein by integrating flexible nonconjugated segments (C6) into the CPs backbone and incorporating quaternary ammonium salt cationic units into the CPs side chain, which considerably increased the radiative decay pathway, resulting in desirable NIR-II FL intensity and balanced NIR-II absorption and NIR PTT properties. The phototheranostic PPN-NO NPs exhibited distinguished NIR-II FL and PA imaging performance in tumor-bearing mice models. Furthermore, the low-temperature photothermal effect of PPN-NO NPs could initiate NO release upon 980 nm laser irradiation, efficiently suppressing tumor growth owing to the combination of low-temperature NIR-II PTT and NO gas therapy in vitro and in vivo.Graphical

Photothermal Temperature-Modulated Cancer Metastasis Harnessed Using Proteinase-Triggered Assembly of Near-Infrared II Photoacoustic/Photothermal Nanotheranostics.

Here we demonstrate that cancer metastasis could be modulated by the judicious tuning of physical parameters such as photothermal temperature in nanoparticle-mediated photothermal therapy (PTT). This is supported by theranostic nanosystem design and characterization, in vitro and in vivo analyses, and transcriptome-based gene profiling. In this work, the highly efficient near-infrared II (NIR-II) photoacoustic image (PA)-guided PTT are selectively activated using our developed matrix metalloproteinase (MMP)-triggered in situ assembly of gold nanodandelions (GNDs@gelatin). Unlike other "always-on" NIR PTT agents lacking specific bioactivation and suffering from the intrinsic nonspecific pseudosignals and treatment-related side effects such as metastasis, our GNDs@gelatin possesses important advantages while deployed in cancer PTT that include the following: (1) The theranostic effects could be "turned on" only after specific MMP-2/-9 activity and with acidity in the tumor microenvironment. (2) The quantitative PA diagnosis allows for precise PTT planning for better cancer treatment. (3) GNDs@gelatin could noninvasively quantify MMP activity and efficiently harness NIR-I (808 nm) and NIR-II (1064 nm) energies for tumor ablation. (4) The multibranched nanostructures reabsorb scattered laser photons, thus enhancing the surface plasmons for the pronounced photothermal conversion of aggregated GNDs@gelatin in situ. (5) It is noteworthy that in situ tumor eradication at higher PTT temperature (>55 °C) mediated by GNDs@gelatin could induce subsequent metastasis, which could be otherwise abolished at lower PTT temperatures (50 °C > T > 43 °C). (6) Furthermore, the gene profiling using transcriptome-based microarray including GO and KEGG analyses revealed that 315 differentially expressed genes were identified in higher PTT temperature treated tumors compared with lower PTT temperature ones. These were enriched into some well-known cancer-related pathways, such as cell migration pathway, signal transductions, cell proliferation, wound healing, PPAR signaling, and metabolic pathways. These observations suggest a new perspective of "moderate-is-better" in nanoparticle-mediated PTT for maximizing its therapeutic/prognosis benefits and translational potential with metastasis inhibition.

Light-activated NIR-II imaging-guided tumor therapy with enhanced HPTT/starvation cycle

Establishing a phototheranostic platform constructed by the second near-infrared (NIR-II) region has proved a revolutionary and promising strategy for cancer treatment. However, the antitumor effectiveness is severely limited by the monotonicity of the NIR-photothermal therapy (HPTT) modality and tumor thermotolerance caused by the production of heat shock proteins (HSPs). Here, a minimalistic approach is used to construct an organic nanoplatform (IFT@PEG-GOX NPs) with the reciprocal cyclic promotion of hypothermia and starvation treatments for NIR-II imaging-guided tumor therapy. After the enhanced permeability and retention (EPR) effect causes IFT@PEG-GOX NPs to accumulate in tumors, glucose oxidase (GOx)-mediated tumor starvation may obstruct the production of adenosine triphosphate (ATP) and downregulation heat shock proteins (HSPs), thereby reducing the thermotolerance of cells. After that, sensitized HPTT was activated and GOx's catalytic activity was increased by NIR laser irradiation. Then, there would be a subsequent, intensified inhibition of HSP along with an additional amplification of the GOx-mediated tumor starvation. As a consequence, the HPTT/Starvation therapy (ST) bidirectional cycle method is initiated, leading to a bidirectional cyclic enhancing impact of HPTT and ST and significantly better tumor suppression.

Acceptor-donor-acceptor-type molecules with large electrostatic potential difference for effective NIR photothermal therapy.

Although acceptor-donor-acceptor (A-D-A)-type molecules offer advantages in constructing NIR absorbing photothermal agents (PTAs) due to their strong intramolecular charge transfer and molecular planarity, their applications in photothermal therapy (PTT) of tumors remain insufficiently explored. In particular, the influence of ESP distribution on the optical properties of A-D-A photosensitizers has not been investigated. Herein, we analyze and compare the difference in ESP distribution between A-D-A-type small molecules and polymers to construct NIR absorbing PTAs with a high extinction coefficient (ε) and high photothermal conversion efficiency (PCE). The calculation results of density functional theory (DFT) indicate that the large ESP difference makes A-D-A-type small molecules superior to their polymer counterparts in realizing tight molecular packing and strong NIR absorbance. Among the as-prepared nanoparticles (NPs), Y6 NPs exhibited an obvious bathochromic shift of absorption peak from 711 nm to 822 nm, with the NIR-II emission extended to 1400 nm. Moreover, a high ε value of 5.69 L g-1 cm-1 and a PCE of 66.3% were attained, making Y6 NPs suitable for PTT. With a concentration of 100 μg mL-1, Y6 NPs in aqueous dispersion yielded a death rate of 93.4% for 4T1 cells upon 808 nm laser irradiation (1 W cm-2) for 10 min, which is comparable with the best results of recently reported PTT agents.

Microenvironment responsive nanocomposite hydrogel with NIR photothermal therapy, vascularization and anti-inflammation for diabetic infected wound healing.

Bacterial infection, excessive inflammation and damaging blood vessels network are the major factors to delay the healing of diabetic ulcer. At present, most of wound repair materials are passive and can't response to the wound microenvironment, resulting in a low utilization of bioactive substances and hence a poor therapeutic effect. Therefore, it's essential to design an intelligent wound dressing responsive to the wound microenvironment to achieve the release of drugs on-demand on the basis of multifunctionality. In this work, metformin-laden CuPDA NPs composite hydrogel (Met@ CuPDA NPs/HG) was fabricated by dynamic phenylborate bonding of gelatin modified by dopamine (Gel-DA), Cu-loaded polydopamine nanoparticles (CuPDA NPs) with hyaluronic acid modified by phenyl boronate acid (HA-PBA), which possessed good injectability, self-healing, adhesive and DPPH scavenging performance. The slow release of metformin was achieved by the interaction with CuPDA NPs, boric groups (B-N coordination) and the constraint of hydrogel network. Metformin had a pH and glucose responsive release behavior to treat different wound microenvironment intelligently. Moreover, CuPDA NPs endowed the hydrogel excellent photothermal responsiveness to kill bacteria of >95% within 10min and also the slow release of Cu2+ to protect wound from infection for a long time. Met@ CuPDA NPs/HG also recruited cells to a certain direction and promoted vascularization by releasing Cu2+. More importantly, Met@CuPDA NPs/HG effectively decreased the inflammation by eliminating ROS and inhibiting the activation of NF-κB pathway. Animal experiments demonstrated that Met@CuPDA NPs/HG significantly promoted wound healing of diabetic SD rats by killing bacteria, inhibiting inflammation, improving angiogenesis and accelerating the deposition of ECM and collagen. Therefore, Met@CuPDA NPs/HG had a great application potential for diabetic wound healing.

A Multifunctional Nano-Delivery System Against Rheumatoid Arthritis by Combined Phototherapy, Hypoxia-Activated Chemotherapy, and RNA Interference.

Effective therapy for rheumatoid arthritis (RA) keeps a challenge due to the complex pathogenesis of RA. It is not enough to completely inhibit the process of RA with any single therapy method. The purpose of the research is to compensate for the insufficiency of monotherapy using multiple treatment regimens with different mechanisms. In this study, we developed a new method to synthesize mesoporous silica nanoparticles hybridized with photosensitizer PCPDTBT (HNs). Branched polyethyleneimine-folic acid (PEI-FA) could be coated on the surface of HNs through electrostatic interactions. It simultaneously blocked the hypoxia-activated prodrug tirapazamine loaded into the mesopores and binded with Mcl-1 siRNA (siMcl-1) that interfered with the expression of the anti-apoptotic protein Mcl-1. Released from the co-delivery nanoparticles (PFHNs/TM) Tirapazamine and siMcl-1 upon exposure to acidic conditions of endosomes/lysosomes in activated macrophages. Under NIR irradiation, photothermal therapy and photodynamic therapy derived from PCPDTBT, hypoxia-activated chemotherapy derived from tirapazamine, and RNAi derived from siMcl-1 were used for the combined treatment for RA by killing activated macrophages. PEI-FA-coated PFHNs/TM exhibited activated macrophage-targeting characteristics, thereby enhancing the in vitro and in vivo NIR-induced combined treatment of RA. The prepared PFHNs/TM have high blood compatibility (far below 5% of hemolysis) and ideal in vitro phototherapy effect while controlling the TPZ release and binding siMcl-1. We prove that PEI-FA-coated PFHNs/TM not only protect the bound siRNA but also are selectively uptaked by activated macrophages through FA receptor-ligand-mediated endocytosis, and effectively silence the target anti-apoptotic protein by siMcl-1 transfection. In vivo, PFHNs/TM have also been revealed to be selectively enriched at the inflammatory site of RA, exhibiting NIR-induced anti-RA efficacy. Overall, these FA-functionalized, pH-responsive PFHNs/TM represent a promising platform for the co-delivery of chemical drugs and nucleic acids for the treatment of RA cooperating with NIR-induced phototherapy.

A plasmon-enhanced fluorescent gold coated novel lipo-polymeric hybrid nanosystem: synthesis, characterization and application for imaging and photothermal therapy of breast cancer.

This study reports a hybrid lipo-polymeric nanosystem (PDPC NPs) synthesized by a modified hydrogel-isolation technique. The ability of the nanosystem to encapsulate hydrophilic and hydrophobic molecules has been demonstrated, and their enhanced cellular uptake has been observed in vitro. The PDPC NPs, surface coated with gold by in situ reduction of chloroauric acid (PDPC-Au NPs), showed a photothermal transduction efficacy of ∼65%. The PDPC-Au NPs demonstrated an increase in intracellular ROS, triggered DNA damage and resulted in apoptotic cell death when tested against breast cancer cells (MCF-7). The disintegration of PDPC-Au NPs into smaller nanoparticles with near-infrared (NIR) laser irradiation was understood using transmission electron microscopy imaging. The lipo-polymeric hybrid nanosystem exhibited plasmon-enhanced fluorescence when loaded with IR780 (a NIR dye), followed by surface coating with gold (PDPC-IR-Au NPs). This paper is one of the first reports on the plasmon-enhanced fluorescence within a nanosystem by simple surface coating of Au, to the best of our knowledge. This plasmon-enhanced fluorescence was unique to the lipo-polymeric hybrid system, as the same was not observed with a liposomal nanosystem. The plasmon-enhanced fluorescence of PDPC-IR-Au NPs, when applied for imaging cancer cells and zebrafish embryos, showed a strong fluorescence signal at minimal concentrations of the dye. The PDPC-IR-Au NPs were also applied for photothermal therapy of breast cancer in vitro and in vivo, and the results depicted significant therapeutic benefits.

Injectable Optical System for Drug Delivery, Ablation, and Sampling in Deep Tissue

AbstractPhotothermal therapy is becoming one subject of intense investigation for cancer treatment. However, due to the light absorption and light scattering of skin tissues, it is challenging to directly transport light energy into subcutaneous tissues with a depth over 1.0 cm. This research puts forward a technique termed as Injectable Optical System (IOS) for guiding near‐infrared light (NIR) into deep tissues by optical fibers, which is unattainable by regular NIR photothermal therapy, despite that NIR light is testified as the preferred light window with deepest tissue penetration. Meanwhile, the technique of IOS also possesses the abilities of drug delivery and synchronous sampling the diseased tissues during the treatment of photothermal therapy. According to in vitro and in vivo studies, IOS exhibits distinct advantages in transporting light energy into deeper subcutaneous tissues in contrast with traditional light irradiation on skins. Light would directly transport through the pathway to tumor tissues to realize hyperthermia effect without causing energy loss. Since IOS owns the benefits of clinical biopsy and radiofrequency ablation, it would be a powerful supplement to therapeutic methodologies for treating subcutaneous diseases. The easy modification of IOS offers great promise to combine other analytical techniques to achieve the in situ detection and deep‐sited tumors treatment.

Brain-Targeted Aggregation-Induced-Emission Nanoparticles with Near-Infrared Imaging at 1550nm Boosts Orthotopic Glioblastoma Theranostics.

A remaining challenge in the treatment of glioblastoma multiforme (GBM) is surmounting the blood-brain barrier (BBB). Such a challenge prevents the development of efficient theranostic approaches that combine reliable diagnosis with targeted therapy. In this study, brain-targeted near-infrared IIb (NIR-IIb) aggregation-induced-emission (AIE) nanoparticles are developed via rational design, which involves twisting the planar molecular backbone with steric hindrance. The resulting nanoparticles can balance competing responsiveness demands for radiation-mediated NIR fluorescence imaging at 1550nm and non-radiation NIR photothermal therapy (NIR-PTT). The brain-targeting peptide apolipoprotein E peptide (ApoE) is grafted onto these nanoparticles (termed as ApoE-Ph NPs) to target glioma and promote efficient BBB traversal. A long imaging wavelength 1550nm band-pass filter is utilized to monitor the in vivo biodistribution and accumulation of the nanoparticles in a model of orthotopic glioma, which overcomes previous limitations in wavelength range and equipment. The results demonstrate that the ApoE-Ph NPs have a higher PTT efficiency and significantly enhanced survival of mice bearing orthotopic GBM with moderate irradiation (0.5Wcm-2 ). Collectively, the work highlights the smart design of a brain-targeted NIR-II AIE theranostic approach that opens new diagnosis and treatment options in the photonic therapy of GBM.

Novel photo-theranostic GdB6 nanoparticles for fluorescence imaging and NIR-photothermal therapy

The development of multifunctional theranostic nano-agents is an important resolution for personalized treatment of cancer. In this work, we synthesized a new kind of gadolinium boride nanoparticles (GBN) by a microwave-assisted chemical etching method, and discovered their optical characteristics including fluorescence imaging and near-infrared (NIR) photothermal conversion capability. Bright greenishyellow fluorescence enabled for intracellular localization, while effective NIR-photothermal conversion supported photothermal therapy (PTT). In vitro and in vivo results indicated that GBN exhibited a superior antitumor performance and high biocompatibility. This study demonstrated a promising multifunctional theranostic nanoplatform for cancer treatment.

A CORM loaded nanoplatform for single NIR light-activated bioimaging, gas therapy, and photothermal therapy in vitro.

Carbon monoxide (CO) can cause mitochondrial dysfunction, inducing apoptosis of cancer cells, which sheds light on a potential alternative for cancer treatment. However, the existing CO-based compounds are inherently limited by their chemical nature, such as high biological toxicity and uncontrolled CO release. Therefore, a nanoplatform - UmPF - that addresses such pain points is urgently in demand. In this study, we have proposed a nanoplatform irradiated by near-infrared (NIR) light to release CO. Iron pentacarbonyl (Fe(CO)5) was loaded in the mesoporous polydopamine layer that was coated on rare-earth upconverting nanoparticles (UCNPs). The absorption wavelength of Fe(CO)5 overlaps with the emission bands of the UCNPs in the UV-visible light range, and therefore the emissions from the UCNPs can be used to incite Fe(CO)5 to control the release of CO. Besides, the catechol groups, which are abundant in the polydopamine structure, serve as an ideal locating spot to chelate with Fe(CO)5; in the meantime, the mesoporous structure of the polydopamine layer improves the loading efficiency of Fe(CO)5 and reduces its biological toxicity. The photothermal effect (PTT) of the polydopamine layer is highly controllable by adjusting the external laser intensity, irradiation time and the thickness of the polydopamine layer. The results illustrate that the combination of CO gas therapy (GT) and polydopamine PTT brought by the final nanoplatform can be synergistic in killing cancer cells in vitro. More importantly, the possible toxic side effects can be effectively prevented from affecting the organism, since CO will not be released in this system without near-infrared light radiation.

Self-Assembling PCL-PAMAM Linear Dendritic Block Copolymers (LDBCs) for Bioimaging and Phototherapeutic Applications.

This study represents a successful approach toward employing polycaprolactone-polyamidoamine (PCL-PAMAM) linear dendritic block copolymer (LDBC) nanoparticles as small-molecule carriers in NIR imaging and photothermal therapy. A feasible and robust synthetic strategy was used to synthesize a library of amphiphilic LDBCs with well-controlled hydrophobic-to-hydrophilic weight ratios. Systems with a hydrophobic weight ratio higher than 70% formed nanoparticles in aqueous media, which show hydrodynamic diameters of 51.6 and 96.4 nm. These nanoparticles exhibited loading efficiencies up to 21% for a hydrophobic molecule and 64% for a hydrophilic molecule. Furthermore, successful cellular uptake was observed via trafficking into endosomal and lysosomal compartments with an encapsulated NIR theranostic agent (C3) without inducing cell death. A preliminary photothermal assessment resulted in cell death after treating the cells with encapsulated C3 and exposing them to NIR light. The results of this work confirm the potential of these polymeric materials as promising candidates in theranostic nanomedicine.

Hollow Prussian Blue Nanospheres for Photothermal/Chemo-Synergistic Therapy.

BackgroundThe integration of NIR photothermal therapy and chemotherapy is considered as a promising technique for future cancer therapy. Hollow Prussian nanospheres have attracted much attention due to excellent near-infrared photothermal conversion effect and drug-loading capability within an empty cavity. However, to date, the hollow Prussian nanospheres have been prepared by a complex procedure or in organic media, and their shell thickness and size cannot be controlled. Thus, a simple and controllable route is highly desirable to synthesize hollow Prussian nanospheres with controllable parameters.Materials and MethodsHere, in our designed synthesis route, the traditional FeCl3 precursor was replaced with Fe2O3 nanospheres, and then the Prussian blue (PB) nanoparticles were engineered into hollow-structured PB (HPB) nanospheres through an interface reaction, where the Fe2O3 colloidal template provides Fe3+ ions. The reaction mechanism and control factors of HPB nanospheres were systematically investigated. Both in vitro and in vivo biological effects of the as-synthesized HPB nanospheres were evaluated in detail.ResultsThrough systematical experiments, a solvent-mediated interface reaction mechanism was put forward, and the parameters of HPB nanospheres could be easily adjusted by growth time and template size under optimal water and ethanol ratio. The in vitro tests show the rapid and remarkable photothermal effects of the as-prepared HPB nanospheres under NIR laser irradiation (808 nm). Meanwhile, HPB nanospheres also demonstrated a high DOX loading capacity of 440 mg g−1 as a drug carrier, and the release of the drug can be regulated by the heat from PB shell under the exposure of an NIR laser. The in vivo experiments confirmed the outstanding performance of HPB nanospheres in photothermal/chemo-synergistic therapy of cancer.ConclusionA solvent-mediated template route was developed to synthesize hollow Prussian blue (HPB) nanospheres in a simple and controllable way. The in vitro and in vivo results demonstrate the as-synthesized HPB nanospheres as a promising candidate due to their low toxicity and high efficiency for cancer therapy.

Mitochondria-targeting supra-carbon dots: Enhanced photothermal therapy selective to cancer cells and their hyperthermia molecular actions

Carbon dots (CDs) have been widely used in biological research including bioimaging, biosensing, and biomedicine because of their excellent biocompatibility. However, inefficient absorption of these CDs in the visible-to-near-infrared window limits their applications for photo-sensitive cancer therapeutic strategies and in vivo imaging. Herein, novel supra-carbon dots (SCDs, approximately 20 nm) with high visible-NIR absorption, large photothermal efficiency, and specific cancer cell and mitochondria-targeting feature were prepared by the self-assembly of small-sized CDs (approximately 5 nm) under an acidic environment, followed by modification of cancer cell- and mitochondria-targeting peptides. These targeting SCDs were applied for precisely damaging cancer cells by an NIR photothermal therapy (PTT), and the viability rate difference between the cancer and normal cells is as large as 70%, indicating high specificity and high selectivity. In addition, the destruction of mitochondria was observed by confocal fluorescence microscopy, and the real-time dynamics of the cellular molecules during this process were further evaluated by surface-enhanced Raman spectroscopy. The results reveal that the produced hyperthermia may first incite structural changes in lipid, protein, and deoxyribonucleic acid and then induce cell death. Our results are helpful for the preparation of new CDs-based photothermal materials and the development of more efficient photothermal therapeutic platforms.

Near-Infrared II Phototherapy Induces Deep Tissue Immunogenic Cell Death and Potentiates Cancer Immunotherapy.

The deep and inner beds of solid tumors lack lymphocytic infiltration and are subjected to various immune escape mechanisms. Reversing immunosuppression deep within the tumor is vital in clinical cancer therapy, however it remains a huge challenge. In this work, we have demonstrated the use of a second window near-infrared (NIR(II)) photothermal treatment to trigger more homogeneous and deeper immunogenic cancer cell death in solid tumors, thereby eliciting both innate and adaptive immune responses for tumor control and metastasis prevention. Specifically, photothermal transducers with similar components, structures, and photothermal conversion efficiencies, but different absorptions in red light, NIR(I), and NIR(II) biowindows, were constructed by controlling the self-assembly of gold nanoparticles on fluidic liposomes. In vitro, photothermal treatments induced immunogenic cell death (ICD) that were accompanied by the release of damage-associated molecular patterns (DAMPs) regardless of the wavelength of incident lasers. In vivo, NIR(II) light resulted in a more homogeneous release and distribution of DAMPs in the deeper parts of the tumors. With the induction of ICD, NIR(II) photothermal therapy simultaneously triggered both innate and adaptive immune responses and enabled efficient tumor control with 5/8 of the mice remaining tumor-free in the cancer vaccination assay. Additionally, the NIR(II) photothermal treatment in combination with checkpoint blockade therapy exerted long-term tumor control over both primary and distant tumors. Finally, using systemically administered two-dimensional polypyrrole nanosheets as a NIR(II) transducer, we achieved striking therapeutic effects against whole-body tumor metastasis via a synergistic photothermal-immunological response.

Black phosphorus–polypyrrole nanocomposites for high-performance photothermal cancer therapy

Black phosphorus–polypyrrole nanosheets with superimposed NIR absorption have been fabricated as the novel nanotherapeutic agent for enhanced NIR photothermal cancer therapy in vitro and in vivo.

Photothermally Active Upconversion Core–Shell NaGdF4:Yb:Tm@Cu Nanostructures: Synthesis and Theranostic Properties

AbstractNear infrared (NIR) active nanostructures with applications in imaging and therapy have attracted significant attention in cancer diagnosis and treatment. NIR active structures can provide molecular images, penetrating from deep within tissue with high resolution. In addition, particles with photothermal properties can lead to a new era of cancer diagnostics. The first synthesis of core–shell NaGdF4:Yb:Tm@Cu (NGF@Cu) nanostructures is reported. NGF@Cu particles have molecular imaging and photothermal activation properties owing to an upconverting core and metallic shell. The upconversion core means that cancer cell location can be recognized and the Cu‐based photothermal therapy is subsequently able to disrupt the cells. NGF@Cu characterization studies, including scanning tunneling electron microscopy and energy dispersive X‐ray spectroscopy mapping, confirm the core–shell structure with Cu as the shell. This study demonstrates the use of a single nanostructure for diagnosis in the NIR therapeutic window (650–1400 nm) and photothermal therapy, with a core–shell particle efficiency of ≈36.3%.

Metal Ion/Tannic Acid Assembly as a Versatile Photothermal Platform in Engineering Multimodal Nanotheranostics for Advanced Applications.

This study reports a family of photothermal materials, metal ion/tannic acid assemblies (MITAs). MITAs from FeIII, VIII, and RuIII afford excellent photothermal efficiency (η ≈ 40%). Sharply differing from the currently existing photothermal agents, MITAs are highlighted by merits including green synthesis, facile incorporation of diagnostic metal ions, and particularly topology-independent adhesion. Owing to the adhesion nature of MITAs, various kinds of MITA-based nanoengineerings are readily available via the self-adhesion of MITAs onto diverse templates, enabling MITAs well suited as a photothermal platform for versatile combination with other therapy approaches and imaging techniques. As a proof of concept, polymeric/inorganic nanoparticle/nanovesicle-supported FeIII-tannic acid (FeIIITA) is fabricated. The photothermal effect is shown to be unaffected by the template origin and type and FeIIITA thickness on the templates. We validate the potency of nanovesicle-supported FeIIITA (PNV@FeIIITA) for tumor-specific photoactivated utilizations, including NIR photothermal therapy with complete tumor elimination, photothermal imaging (PTI), and photoacoustic imaging (PAI) in addition to T1-MRI imaging. PNV@FeIIITA can be simultaneously equipped with functionalities, including T2-MRI imaging by additionally doping MnII and NIR fluorescence imaging by encapsulating a hydrophilic NIR fluoroprobe. MITA demonstrates unparalleled superiority as a photothermal platform in engineering multimodal theranostics for advanced applications.

Hollow mesoporous silica nanosphere-supported FePt nanoparticles for potential theranostic applications.

A facile preparation of a nanocomposite comprising FePt nanoparticles (NPs) and hollow mesoporous silica nanospheres (HMSNs) was reported. The bimetallic NPs had an alloy structure with Pt-rich cores and were highly dispersed on the mesoporous shell of HMSNs. The material, designated as FePt@MMT-2, could be gradually degraded and dissolved under physiological conditions and showed low cytotoxicity against HeLa cells. FePt@MMT-2 exhibited ferromagnetic-like properties and broadband near-infrared (NIR) absorption along with high photothermal transduction efficiency. In addition, in vitro studies showed high efficacy of FePt@MMT-2 in killing HeLa cells with 1064 nm NIR irradiation, and synergistic anticancer effects when combined with chemo drug topotecan. The results demonstrated the potential of the designed nanocomposite for theranostic applications.