Photothermal Therapy Applications Research Articles

Synergetic effect of Hexaferrite and reduced Graphene oxide (rGO) in Photothermal therapy and Hyperthermia applications

This research article describes the synthesis of composite materials by combining T-type hexagonal ferrite and reduced Graphene Oxide using the standard ceramic process. The Calcium-based T-type hexagonal ferrite was synthesized by using the sol-gel auto-combustion method whiles the reduced graphene oxide by adopting the Hummer method. The crystallite size varied in the range of 34.11 to 42.07nm as calculated from the X-ray diffraction (XRD) data. Consequently, the lattice parameters 'a' and 'c' decreased from 5.9 to 5.1Å and from 29.92 to 28.32Å, respectively. The use of atomic force microscopy (AFM) revealed a range of particle sizes at the surface, varying from 1.70nm to 3.85nm. Moreover, the saturation and remanence magnetization values demonstrated an increasing trend with T-type hexaferrites concentration whereas the coercivity decreased. The UV-vis near-infrared spectra exhibited substantial light absorption, characterized by a wide absorption range in the visible and near-infrared (NIR) region (700 to 1100nm) which indicates its use in Photothermal therapy (PTT). The Calcium T- type hexaferrite exhibited clear peaks in the blue, green, violet, and yellow spectra in its photoluminescence (PL) properties. These peaks are believed to be caused by oxygen vacancies and defects. The synthesized samples displayed a lossy behavior in the polarization-electric field (P-E) loop, with saturation polarization levels exceeding remnant polarization, which is an amenable condition for lossy behavior. Most importantly, the synthesized materials had significant thermal responses when exposed to an alternation (AC) magnetic field, indicating their potential use in magnetic hyperthermia applications.

Localized surface plasmon resonance induced nonlinear absorption and optical limiting activity of gold decorated graphene/MoS2 hybrid

The synergistic supremacy of a hybrid nanocomposite made of reduced graphene oxide (rGO), molybdenum disulfide (MoS2) and gold nanoparticles (Au) for Q-switching and optical limiting applications is investigated. Hydrothermally synthesized Au-rGO-MoS2 hybrid with varying concentrations of Au (2.5, 5, 7.5 and 10 wt%) was subjected to interact with Q-switched Nd:YAG nanosecond green laser pulses. The intensity dependent nonlinear absorption studies revealed a switch over in the nonlinear behaviour from saturable absorption (SA) to reverse saturable absorption (RSA) behaviour. SA occurs due to ground state bleaching at comparatively lower laser irradiances serving the need for Q-switching and optical communications. The RSA trait at higher laser irradiance is attributed to sequential two-photon absorption which serves as the platform for optical limiting behaviour prompting laser safety and effective photothermal therapy applications. The strong mid-visible and UV absorption promotes the availability of multiple energy bands for energy transitions of excited state absorption (ESA). Enhanced local fields due to localized surface plasmon resonance effect, structural defects, hierarchical morphology, increased absorption cross-section and plasmon induced energy transfer promotes robust ESA process. These tunable nonlinear optical properties make Au-rGO-MoS2 hybrid promising futuristic candidates for applications in nonlinear photonic devices, ultrafast optical switches and all-optical signal processing systems.

Analysis and Optimization of Light Absorption and Scattering Properties of Metal Nanocages.

Metal nanocages exhibit localized surface plasmon resonance that strongly absorbs and scatters light at specific wavelengths, making them potentially valuable for photothermal therapy and biological imaging applications. However, investigations on metal nanocages are still confined to high-cost and small-scale synthesis. The comprehensive analysis of optical properties and optimal size parameters of metal nanocages is rarely reported. This paper simulates the effects of materials (Ag, Au, and Cu), size parameters, refractive index of the surrounding medium, and orientation on the light absorption and scattering characteristics of the nanocages using the finite-element method and the size-dependent refractive-index model for metal nanoparticles. The results show that the Ag nanocages have excellent light absorption and scattering characteristics and respond significantly to the size parameters, while the refractive index and orientation of the surrounding medium have less effect on them. The Au nanocages also possess superior light absorption properties at specific incident wavelengths. This study also identified the optimized sizes of three metal nanocages at incident light wavelengths commonly used in biomedicine; it was also found that, under deep therapy conditions, Ag nanocages in particular exhibit the highest volume absorption and scattering coefficients of 0.708 nm-1 and 0.583 nm-1, respectively. These findings offer theoretical insights into preparing target nanocage particles for applications in photothermal therapy and biological imaging.

Photothermal Properties of Solid-Supported Gold Nanorods.

Gold nanoparticles possess unique photothermal properties and have gained considerable interest in biomedical research, particularly for photothermal therapy (PTT). This study focuses on evaluating the photothermal properties of gold nanorods (AuNRs) supported on glass substrates upon excitation with near-infrared (NIR) light. Two aspect ratios of AuNRs were electrostatically immobilized onto glass with controlled coverage. In situ X-ray diffraction (XRD) was performed to evaluate the photothermal behavior and morphological changes of the supported AuNRs during NIR laser irradiation. The XRD data sets were corroborated with scanning electron microscopy and Vis-NIR spectroscopy characterization. XRD revealed a linear temperature increase with laser power, aligning with theoretical predictions, and a slope dependent on the AuNR coverage, until the onset of morphology transformations around 120 °C. This study provides valuable insights into the photothermal properties of supported AuNRs, crucial for their application in PTT.

Polyphosphate-Mediated Crystallographic and Colloidal Stabilization of CuS Nanoparticles: Enhanced NIR-Responsive Chemo-Photothermal Efficacy.

Photothermal therapy (PTT) is an emerging treatment modality for cancer management. However, the photothermal agents (PTAs) used in PTT should have sufficient biocompatibility, water dispersibility, and good photoresponsive. In this aspect, water-dispersible and biocompatible linear polyphosphate (LP)-functionalized CuS nanoparticles (LP-CuS NPs) were developed using sodium tripolyphosphate (LP molecule) as a surface passivating agent. The successful formation of the green covellite CuS phase was confirmed by X-ray diffraction and TEM analyses, and its surface functionalization with the LP ligand was evident from X-ray photoelectron spectroscopy, Fourier transform infrared, thermogravimetric analysis, and light scattering measurements. It has been found that the use of LP not only stabilizes the crystallographic covellite CuS phase by overcoming the requirement of a soft ligand but also provides long-term aqueous colloidal stability, which is essential for PTT applications. The aqueous suspension of LP-CuS NPs showed excellent heating efficacy under near infrared (NIR) light irradiation (980 nm) and has a strong binding affinity towards anticancer drug, doxorubicin hydrochloride (DOX). The drug-loaded systems (DOX@LP-CuS NPs) revealed a pH-dependent drug release behavior with higher concentrations in a mild acidic environment. The in vitro studies showed substantial cellular uptake of DOX-loaded systems in cancer cell lines and enhanced toxicity towards them upon irradiation of NIR light through apoptotic induction, suggesting their potential application in chemo-photothermal therapy.

Aggregation-Induced Emission-Active Organic Nanoagent with High Photothermal Conversion Efficiency for Near-Infrared Imaging-Guided Tumor Photothermal Therapy.

Photothermal therapy (PTT) provides a great prospect for noninvasive cancer therapy. However, it is still highly challenging to construct photothermal agents (PTAs) with the desired performances for imaging-guided PTT applications. Herein, a D-A-D-type naphthalene diamine (NDI)-based photothermal nano-PTAs NDS-BPN NP with near-infrared region (NIR) emission at 822 nm, aggregation-induced emission (AIE), high photothermal conversion efficiency (55.05%), and excellent photothermal stability is successfully designed and prepared through a simple two-step engineering method by using a new AIE molecule NDS-BPN and DSPE-PEG2000 as precursors. The prepared PTT nanoagents NDS-BPN NPs have been further applied for efficient photothermal ablation of cancer cells in vitro and also achieved the NIR fluorescent image-guided PTT tumor therapy in vivo with satisfactory results. We believe that this work provides an attractive NIR AIE NDI-based nano-PTA for the phototherapy of tumors as well as develops the construction strategy of NDI molecular-based photothermal nanoagents with desired performances for imaging-guided PTT.

Research Progress of Cyanine-based Near-Infrared Fluorescent Probes for Biological Application.

Cyanine-based near-infrared (NIR) fluorescent probes have played vital roles in biological application due to their low interference from background fluorescence, deep tissue penetration, high sensitivity, and minimal photodamage to biological samples. They are widely utilized in molecular recognition, medical diagnosis, biomolecular detection, and biological imaging. Herein, we provide a review of recent advancements in cyanine-based NIR fluorescent probes for the detection of pH, cells, tumor as well as their application in photothermal therapy (PTT) and photodynamic therapy (PDT).

Positron Emission Tomography‐Assisted Photothermal Therapy with Gold Nanorods

AbstractPhotothermal anticancer therapy based on plasmonic nanoparticles is proposed to enhance treatment efficacy while mitigating unintended side effects. However, most studies blindly rely on the accumulation of nanoparticles at the tumor site, which may result in inefficient treatment. In this study, the aim is to evaluate relevant parameters to improve plasmonic photothermal therapy. Gold nanorods (AuNRs) with an optimized aspect ratio and either amino or carboxylic acid surface functionalization are selected as photothermal agents. AuNR biocompatibility and photothermal activity in 2D and 3D human MDA‐MB‐231 triple‐negative breast cancer cell models, evaluating localized hyperthermal cell death upon irradiation with resonant near‐infrared (NIR) light, are analyzed first. To ensure reliable tracking of biodistribution in vivo, AuNRs are labeled with the positron emitter copper‐64 (64Cu), and their distribution in a murine MDA‐MB‐231 tumor model is studied via positron emission tomography (PET) imaging. PET images reveal enhanced tumor accumulation of carboxylic acid‐functionalized AuNRs compared to amino‐functionalized AuNRs post‐intravenous administration. Relatively low NIR laser power densities (0.5 W cm−2) are used for controlled heating – keeping local temperature below 50 °C – upon irradiation of intravenously and intratumorally administered AuNRs. As a result, tumor growth is significantly decelerated, even 9 days after application of photothermal therapy.

High-Performance NIR-II Fluorescent Type I/II Photosensitizer Enabling Augmented Mild Photothermal Therapy of Tumors by Disrupting Heat Shock Proteins.

NIR-II fluorescent photosensitizers as phototheranostic agents hold considerable promise in the application of mild photothermal therapy (MPTT) for tumors, as the reactive oxygen species generated during photodynamic therapy can effectively disrupt heat shock proteins. Nevertheless, the exclusive utilization of these photosensitizers to significantly augment the MPTT efficacy has rarely been substantiated, primarily due to their insufficient photodynamic performance. Herein, the utilization of high-performance NIR-II fluorescent type I/II photosensitizer (AS21:4) is presented as a simple but effective nanoplatform derived from molecule AS2 to enhance the MPTT efficacy of tumors without any additional therapeutic components. By taking advantage of heavy atom effect, AS21:4 as a type I/II photosensitizer demonstrates superior efficacy in producing 1O2 (1O2 quantum yield = 12.4%) and O2 •- among currently available NIR-II fluorescent photosensitizers with absorption exceeding 800nm. In vitro and in vivo findings demonstrate that the 1O2 and O2 •- generated from AS21:4 induce a substantial reduction in the expression of HSP90, thereby improving the MPTT efficacy. The remarkable phototheranostic performance, substantial tumor accumulation, and prolonged tumor retention of AS21:4, establish it as a simple but superior phototheranostic agent for NIR-II fluorescence imaging-guided MPTT of tumors.

Development of dual-crosslinked Pluronic F127/Chitosan injectable hydrogels incorporating graphene nanosystems for breast cancer photothermal therapy and antibacterial applications

Nanomaterials with responsiveness to near-infrared light can mediate the photoablation of cancer cells with an exceptional spatio-temporal resolution. However, the therapeutic outcome of this modality is limited by the nanostructures’ poor tumor uptake. To address this bottleneck, it is appealing to develop injectable in situ forming hydrogels due to their capacity to perform a tumor-confined delivery of the nanomaterials with minimal off-target leakage. In particular, injectable in situ forming hydrogels based on Pluronic F127 have been emerging due to their FDA-approval status, biocompatibility, and thermosensitive sol–gel transition. Nevertheless, the application of Pluronic F127 hydrogels has been limited due to their fast dissociation in aqueous media. Such limitation may be addressed by combining the thermoresponsive sol–gel transition of Pluronic F127 with other polymers with crosslinking capabilities. In this work, a novel dual-crosslinked injectable in situ forming hydrogel based on Pluronic F127 (thermosensitive gelation) and Chitosan (ionotropic gelation in the presence of NaHCO3), loaded with Dopamine-reduced graphene oxide (DOPA-rGO; photothermal nanoagent), was developed for application in breast cancer photothermal therapy. The dual-crosslinked hydrogel incorporating DOPA-rGO showed a good injectability (through 21 G needles), in situ gelation capacity and cytocompatibility (viability > 73 %). As importantly, the dual-crosslinking improved the hydrogel’s porosity and prevented its premature degradation. After irradiation with near-infrared light, the dual-crosslinked hydrogel incorporating DOPA-rGO produced a photothermal heating (ΔT ≈ 22 °C) that reduced the breast cancer cells’ viability to just 32 %. In addition, this formulation also demonstrated a good antibacterial activity by reducing the viability of S. aureus and E. coli to 24 and 33 %, respectively. Overall, the dual-crosslinked hydrogel incorporating DOPA-rGO is a promising macroscale technology for breast cancer photothermal therapy and antimicrobial applications.

(Invited) Mie Resonant Silicon Nanospheres for Scattering-Fluorescence Dual-Mode Imaging, Medical Diagnosis and Photothermal Therapy

In recent years, a variety of multimodal and multifunctional nanoparticles have been developed for biomedical applications such as cellular imaging, biomolecule detection, and medical diagnosis and treatment. A common platform of multifunction nanoparticles is metallic ones with localized surface plasmon resonances. A drawback of metallic nanoparticles for biomedical applications is the Ohmic loss that leads to fluorescence quenching of attached molecules and local heating under light irradiation. We have been developing metal-free nanoprobes capable of scattering/fluorescence dual-mode imaging, medical diagnosis and photothermal therapy. The nanoprobes are composed of a silicon nanosphere core having Mie resonances in the visible to near infrared range and a fluorophore-doped silica shell [1, 2]. In this presentation, we first show scattering properties of the Mie resonant Si nanospheres. We then discuss the dark-field scattering and photoluminescence images/spectra of the core-shell nanoparticles and demonstrate that the fluorescence spectra are strongly modified by the Mie modes of a silicon nanosphere core by the Purcell effect. We demonstrate in the in vitro imaging of human cancer cells that the developed core-shell nanoparticles work as scattering/fluorescence dual-mode imaging nanoprobes.We then add the capability of glutathione sensing to the core-shell nanoprobes. It is known that the glutathione level tends to be elevated in some kinds of cancers and thus it can be used as a biomarker. To add the capability of glutathione sensing, we cover the surface of the core-shell nanoprobes with manganese oxide (MnO2). MnO2 quenches the fluorescence of the core-shell nanoparticles, and it is recovered if the MnO2 shell is resolved by the reaction with glutathione. Therefore, we can monitor the glutathione level by the fluorescence intensity. The advantage of the dual-mode imaging is that the glutathione level can be monitored by the fluorescence intensity, while the particle position is always monitored by the scattering image.Finally, we discuss the capability of Si nanospheres for photothermal therapy. We show that Si nanospheres exhibit efficient light absorption at the wavelengths of magnetic type Mie resonances such as magnetic dipole (MD) and magnetic quadrupole (MQ) resonances, and can be heated up very easily by light irradiation. An advantage of Si nanospheres compared to plasmonic nanoparticles as a light absorber for photothermal therapy is the much narrower resonances. Because of the narrow resonance, we can easily switch heating and non-heating modes. This means that if we want to heat up a nanoparticle, we can choose a specific wavelength that corresponds to e.g., the MQ mode, while if we want to excite fluorophores without heating, we can choose off-resonance wavelength for the excitation. Another advantage of Si nanospheres is the capability to monitor the temperature by Raman scattering. We show the relation between the temperature, wavelength and the size of silicon nanospheres and discuss the Mie modes suitable for the photothermal therapy application.

Design of Biopolymer-Coated Gold Nanorods as Biorelevant Photothermal Agents.

Gold nanorods (AuNRs) are emerging metallic nanoparticles utilized to generate heat for photothermal therapy (PTT) in cancer. The tunable plasmonic properties of AuNRs make them a remarkable candidate for hyperthermia. However, the cytotoxicity of AuNRs limits its biological applicability due to the existence of cetyltrimethylammonium bromide (CTAB) on the surface as a common surfactant. In this study, AuNRs are synthesized by seed-mediated growth and then the optical properties are optimized by altering AgNO3 concentration. Afterward, CTAB is replaced with biopolymers which are BSA:Dextran and BSA:Guar Gum conjugates resulting in enhanced cellular viability, enabling to use of them as biologically relevant photothermal agents. The biocompatibility of AuNRs is improved to utilize them at high concentrations for laser studies, in which similar heat generation success of CTAB- and biopolymer-coated AuNRs are shown for potential PTT applications. CTAB and biopolymer-coated AuNRs in concentrations of 0.5 and 1mg mL-1 are irradiated under NIR light at 808nm laser at 0.5, 0.75, and 1W cm-2 for 300 s. The biopolymer-coated gold nanorods with different coatings preserve photothermal properties while reducing the cytotoxicity effects of CTAB and thus they are promising photothermal agents for potential PTT.

Hydrogen Sulfide Delivery System Based on Salting-Out Effect for Enhancing Synergistic Photothermal and Photodynamic Cancer Therapies.

The simultaneous application of photothermal therapy (PTT) and photodynamic therapy (PDT) offers substantial advantages in cancer treatment. However, their synergistic anticancer efficacy is often limited by tumor hypoxia, and thermotolerance induced by high expression of heat shock proteins (HSP). Fortunately, hydrogen sulfide (H2S), known for its direct cytotoxic effect on tumor cells, has been recognized for its ability to enhance PTT and PDT. The effectiveness of H2S in these therapies is challenged by its low loading efficiency, poor stability, and short diffusion distance. To address these issues, a nanoscale emulsion drop template created through the salting-out effect is employed to construct a robust H2S delivery system. Polydopamine (PDA), chosen for its interfacial polymerization tendency and excellent photothermal conversion rate, is utilized as a carrier for the H2S donor (ADT) and Zinc phthalocyanine (ZnPc) to fabricate a novel nanomedicine termed APZ NPs. The temperature-responsive APZ NPs are designed to release H2S during the PTT process. Elevated H2S levels promoted vasodilation, thereby enhancing the enhanced permeability and retention effect (EPR) of APZ NPs within solid tumors. This strategy effectively alleviated tumor hypoxia by disrupting the mitochondrial respiratory chain and mitigated tumor cell heat tolerance by inhibiting HSP expression.

Biomimetic Nanosystem Loading Aggregation-Induced Emission Luminogens and SO2 Prodrug for Inhibiting Insufficient Photothermal Therapy-Induced Breast Cancer Recurrence and Metastasis.

Photothermal therapy (PTT) holds considerable clinical promise. However, insufficient PTT-induced tumor recurrence and metastasis is an urgent practical problem that needs to be solved. Herein, a biomimetic mesoporous organosilicon nano-system called PSAB is designed to precisely deplete cancer stem cells (CSCs) and prevent tumor recurrence and metastasis after PTT. The PSAB system is made up of Aggregation-induced emission (AIE)-active photothermal agent, 2TT-oC26B, and SO2 prodrug, benzothiazole sulfinate (BTS), within mesoporous organosilicon nanoparticles (MON) enclosed by an exterior platelet membrane. PSAB effectively targets CSCs both in vitro and in vivo by P-selectin/CD44 interaction. The degradation of MON and subsequent release of BTS and AIE molecules are facilitated by intracellular glutathione (GSH). Subsequently, the acidic tumor environment triggers the SO2 gas therapy from BTS. This process leads to the depletion of GSH and CSCs elimination. After combining PSAB with photothermal therapy, there is no significant tumor recurrence or metastasis. These results indicate that SO2 gas therapy and AIE-mediated PTT act synergistically to offer a unique approach for preventing tumor recurrence and metastasis after PTT, thus holding significant promise for clinical applications in cancer PTT.

Fully conjugated radical-doped COF for near-infrared photothermal conversion, C-3 thiocyanation of indoles and oxidative coupling of amines

Radical-doped covalent organic frameworks (COFs) have received much interest as it confers additional functions such as photomodulated electrical conductivity, magnetism, and photochromism. Such COFs are relatively underexplored, however, mainly due to the lack of suitable highly photoactive building blocks. Herein, a rare radical-doped fully conjugated COF (PDI-COF) was rationally designed and prepared by incorporating photoactive perylenediimides (PDIs) into its framework. Characterization of the product PDI-COF not only confirmed its porous and stable skeleton, but also revealed the radical derived from photoinduced electron transfer between the PDI and electron donor. The fully conjugated and radical-doped characteristics enable the effective realization of near-infrared photothermal conversion in this COF. Moreover, this radical-doped COF can efficiently generate superoxide radical anions under light irradiation, which promote the photocatalytic C-3 thiocyanation of indoles and the oxidative coupling of amines in high yield and good recyclability at room temperature and without additives. This study demonstrates that introducing a photoactive organic dye into a COF is an effective approach to photothermal conversion materials and metal-free porous photocatalysts for application in photothermal therapy and photocatalytic organic synthesis.

Photothermal Depth Profiling of Gelatin-Stabilised Gold Nanorods-Trastuzumab Conjugate as a Potential Breast Cancer Photothermal Agent

AbstractGold nanorods (AuNRs) are powerful photothermal agents (PTAs) in cancer treatment due to their near-infrared laser light absorption ability. However, the cytotoxicity of AuNRs caused by the presence of cationic surfactants often used and their lack of specificity affect their application in photothermal therapy. Thus, we herein developed a bioconjugate obtained from the functionalisation of AuNRs to gelatin (Gel@AuNRs), followed by the conjugation of the as-synthesised material to a breast cancer antibody, trastuzumab (Trast-Gel@AuNRs) to address these issues. The optical and structural characterization of the as-synthesized indicated no significant changes in the optical properties of AuNRs after their functionalisation with gelatin and conjugation with the antibody. The photothermal profiling of the as-synthesised materials showed that AuNRs still have an excellent photothermal conversion efficiency (PCE) after their functionalisation (20%) and their conjugation to an antibody (19%). In addition, the In vitro photothermal depth response showed that Trast-Gel@AuNRs is a promising photothermal agent for HER2-positive breast cancer treatment. Graphical Abstract

Fe3O4 Nanoparticles That Modulate the Polarisation of Tumor-Associated Macrophages Synergize with Photothermal Therapy and Immunotherapy (PD-1/PD-L1 Inhibitors) to Enhance Anti-Tumor Therapy.

Traditional surgical resection, radiotherapy, and chemotherapy have been the treatment options for patients with head and neck squamous cell carcinoma (HNSCC) over the past few decades. Nevertheless, the five-year survival rate for patients has remained essentially unchanged, and research into treatments has been relatively stagnant. The combined application of photothermal therapy (PTT) and immunotherapy for treating HNSCC has considerable potential. Live-dead cell staining and CCK-8 assays proved that Fe3O4 nanoparticles are biocompatible in vitro. In vitro, cellular experiments utilized flow cytometry and immunofluorescence staining to verify the effect of Fe3O4 nanoparticles on the polarisation of tumor-associated macrophages. In vivo, animal experiments were conducted to assess the inhibitory effect of Fe3O4 nanoparticles on tumor proliferation under the photothermal effect in conjunction with BMS-1. Tumour tissue sections were stained to observe the effects of apoptosis and the inhibition of tumor cell proliferation. The histological damage to animal organs was analyzed by hematoxylin and eosin (H&E) staining. The stable photothermal properties of Fe3O4 nanoparticles were validated by in vitro cellular and in vivo animal experiments. Fe3O4 photothermal action not only directly triggered immunogenic cell death (ICD) and enhanced the immunogenicity of the tumor microenvironment but also regulated the expression of tumor-associated macrophages (TAMs), up-regulating CD86 and down-regulating CD206 to inhibit tumor growth. The PD-1/PD-L1 inhibitor promoted tumor suppression, and reduced tumor recurrence and metastasis. In vivo studies demonstrated that the photothermal action exhibited a synergistic effect when combined with immunotherapy, resulting in significant suppression of primary tumors and an extension of survival. In this study, we applied Fe3O4 photothermolysis in a biomedical context, combining photothermolysis with immunotherapy, exploring a novel pathway for treating HNSCC and providing a new strategy for effectively treating HNSCC.

Tumor microenvironment responsive chitosan-coated W-doped MoOx biodegradable composite nanomaterials for photothermal/chemodynamic synergistic therapy

Chemodynamic therapy (CDT), an approach that eradicates tumor cells through the catalysis of hydrogen peroxide (H2O2) into highly toxic hydroxyl radicals (·OH), possesses distinct advantages in tumor specificity and minimal side effects. However, CDT's therapeutic efficacy is currently hampered by the low production efficiency of ·OH. To address this limitation, this study introduces a water-soluble chitosan-coated W-doped MoOx (WMoOx/CS) designed for the combined application of photothermal therapy (PTT) combined with CDT. The W-doped MoOx (WMoOx) was synthesized in one step by the hydrothermal method, and its surface was modified by water-soluble chitosan (carboxylated chitosan, CS) to enhance its biocompatibility. WMoOx boasts a high near-infrared photothermal conversion efficiency of 52.66 %, efficiently transducing near-infrared radiation into heat. Moreover, the Mo4+/Mo5+ and W5+ ions in WMoOx catalyze H2O2 to produce ·OH for CDT, and the Mo5+/Mo6+ and W6+ ions in WMoOx reduce intracellular glutathione levels and prevent the scavenging of ·OH by glutathione. Crucially, the combination of WMoOx/CS and near-infrared light irradiation demonstrates promising synergistic antitumor effects in both in vitro and in vivo models, highlighting its potential for the combined application of PTT and CDT.

Comparison of alternative gold nanoparticles (AuNPs) produced by laser ablation technique for photothermal therapy applications

Comparison of alternative gold nanoparticles (AuNPs) produced by laser ablation technique for photothermal therapy applications

Highly Effective Pyroelectric Catalysis for Simultaneous Tumor-Targeted Dynamic Therapy and Gentle Photothermal Therapy by Oxygen-Vacancy-Rich CeO2-BaTiO3 Nanorods.

Pyroelectric nanostructures can effectively generate temperature-mediated reactive oxygen species (ROS) through the pyroelectric effect, providing promise for treating hypoxic tumors; and therefore, the synergistic application of photothermal therapy (PTT) and pyroelectric dynamic therapy (PEDT) presents an intriguing approach for cancer therapy. However, this method still faces challenges in improving pyroelectric catalysis and achieving precise tumor localization. In this study, a nano-heterojunction based on CeO2-BaTiO3 nanorods (IR1061@PCBNR) is reported, which exhibits highly effective pyroelectric catalysis for simultaneous tumor-targeted dynamic therapy and gentle photothermal therapy through the utilization of the rich oxygen vacancies. The oxygen vacancies create active sites that facilitate the migration of pyroelectrically-induced charge carriers, improving charge separation and ROS generation. IR1061@PCBNR also demonstrates high tumor penetration; while, minimizing damage to normal cells. This precise nanomedicine strategy holds great potential for advancing dynamic cancer therapies by overcoming the limitations of conventional approaches.