UV-C driven reduction of nanographene oxide opens path for new applications in phototherapy

The main challenges associated to the application of graphene-based materials (GBM) in phototherapy are obtaining particles with lateral nanoscale dimensions and water stability that present high near-infrared (NIR) absorption. Nanosized graphene oxide (GOn) is stable in aqueous dispersion, due to the oxygen functionalities on its surface, but possesses low photothermal efficiency in NIR region. GOn total reduction originates reduced nanographene oxide (rGOn) that presents high NIR absorption, but poor water stability. In this work, we produced a partially reduced nanographene oxide (p-rGOn) by GOn photoreduction using ultraviolet radiation (UV-C), yielding nanometric particles that preserve the original water stability, but acquire high light-to-heat conversion efficiency. GOn and p-rGOn presented mean particle sizes of 170 ± 81 nm and 188 ± 99 nm, respectively. 8 h of UV-C irradiation allowed to obtain a p-rGOn stable for up 6 months in water, with a zeta potential of -32.3 ± 1.3 mV. p-rGOn water dispersions have shown to absorb NIR radiation, reaching 52.7 °C (250 µg mL-1) after 30 min NIR irradiation. Chemical characterization of p-rGOn showed a decrease in the number of characteristic oxygen functional groups, confirming GOn partial reduction. Furthermore, p-rGOn (250 µg mL-1) didn't cause any cytotoxicity (ISO10993-5:2009(E)) towards human skin fibroblasts (HFF-1) and human skin keratinocytes (HaCat), after 24 and 48 h incubation. An innovative custom-built NIR LED-system has been developed and validated for p-rGOn photothermal effect evaluation. Finally, exposure to p-rGOn+NIR-LEDs has caused no cytotoxicity towards HFF-1 or HaCat cells, revealing its potential to be used as a safe therapy.

Preparation and photothermal therapy of gold nanorods modified by Belamcanda chinensis (L.) DC polysaccharide

In recent years, the application of nanoparticles formed by coupling metal nanomaterials of photothermal therapy with polysaccharides as modified carriers in the targeted treatment of liver cancer has attracted extensive attention. In the present work, an undescribed homogeneous polysaccharide BCP50-2 was obtained from Belamcanda chinensis (L.) DC. The structural analysis displayed that BCP50-2 contained galactose and a small amount of arabinose, and was mainly composed of six monosaccharide residues: →3,5)-α-l-Araf-(1→, →4)-β-d-Galp-(1→, →4,6)-β-d-Galp-(1→, →3)-α-l-Galp-(1→, terminal α-l-Araf, and terminal β-d-Galp. To enhance the antitumor activity of BCP50-2, BCP50-2-AuNRs were prepared by coupling BCP50-2 with gold nanorods for the treatment of liver cancer. BCP50-2-AuNRs were rod-shaped with a long diameter of 26.8 nm and had good photothermal conversion effects. Under near-infrared (NIR) light irradiation, BCP50-2-AuNRs possessed photothermal effects and suppressed the growth of HepG2, A549, and MCF-7 cells. In addition, BCP50-2-AuNRs inhibited the development of liver cancer by inducing cell apoptosis, arresting the cell cycle in G2/M phases, and inhibiting cell migration. Moreover, BCP50-2-AuNRs inhibited tumor proliferation, migration, and angiogenesis in zebrafish. In summary, BCP50-2-AuNRs may be potentially useful for cancer treatment.

2D silicene nanosheets-loaded coating for combating implant-associated infection

Implant-associated infection (IAI) is an unsolved problem in orthopaedics. Current therapies, including antibiotics and surgical debridement, can lead severe clinical and financial burdens on patients. Therefore, there is an urgent need to reinforce the inherent antibacterial properties of implants. Recently, two-dimensional (2D) silicene nanosheets (SNs) have gained increasing attention in biomedical fields owing to their considerable biocompatibility, biodegradability and strong photothermal-conversion performance. Herein, a dual-functional photosensitive coating on a Ti substrate (denoted as TPSNs) was rationally fabricated for bacterial inhibition and osteogenesis promotion. For the first time, SNs were loaded onto the surface of implants. Hyperthermia generated by the SNs and polydopamine (PDA) coating under 808 nm laser irradiation achieved the in vitro anti-bacterial efficiency of 90.7 ± 2.4 % for S. aureus and 88.0 ± 5.8 % for E. coli, respectively. In addition, TPSNs exhibited promising biocompatibility for the promotion of BMSC (bone marrow mesenchymal stem cells) proliferation and spreading. The presence of silicon (Si) in TPSNs contributed to the improved osteogenic differentiation of BMSCs, elevating the expressions of RUNX2 and OCN. In animal experiments, the combination of TPSNs with photothermal therapy (PTT) achieved an anti-bacterial efficiency of 89.2 % ± 1.6 % against S. aureus. Furthermore, TPSNs significantly improved bone-implant osseointegration in vivo. Overall, the development of a dual-functional TPSNs coating provides a new strategy for combating IAI.

A novel polymer enabled by polymerized small molecule strategy for tumor photothermal and photodynamic therapy

Photothermal therapy (PTT) and photodynamic therapy (PDT) are effective method for tumor treatment. However, the limited variety and quantity of photothermal agents (PTAs) and photosensitizer (PSs) are still major challenges. Moreover, the cell apoptosis mechanism induced by PDT and PTT is still elusive. A fused-ring small molecule acceptor-donor acceptor' donor-acceptor (A-DA'D-A) type of Y5 (Scheme 1) has a narrow band-gap and strong light absorption. Herein, we used Y5 to polymerize with thiophene unit to obtain polymer PYT based on polymerized small molecule strategy, and PYT nanoparticles (PYT NPs) was prepared via one-step nanoprecipitation strategy with DSPE-PEG2000. PYT NPs had excellent biocompatibility, good photostability, high photothermal conversion efficiency (67%) and reactive oxygen species (ROS) production capacity under 808 nm laser irradiation (PYT NPs + NIR). In vitro and in vivo experiments revealed that PYT NPs + NIR had the ability to completely ablate tumor cells. It was demonstrated that cell apoptosis induced by PYT NPs + NIR was closely related to mitochondrial damage. This study provides valuable guidance for constructing high-performance organic PTAs and PSs for tumor treatment. Scheme 1 PYT enabled by polymerized small molecule strategy for tumor photothermal and photodynamic therapy.

Rational design of NIR-II molecule-engineered nanoplatform for preoperative downstaging and imaging-guided surgery of orthotopic hepatic tumor

Orthotopic advanced hepatic tumor resection without precise location and preoperative downstaging may cause clinical postoperative recurrence and metastasis. Early accurate monitoring and tumor size reduction based on the multifunctional diagnostic-therapeutic integration platform could improve real-time imaging-guided resection efficacy. Here, a Near-Infrared II/Photoacoustic Imaging/Magnetic Resonance Imaging (NIR-II/PAI/MRI) organic nanoplatform IRFEP-FA-DOTA-Gd (IFDG) is developed for integrated diagnosis and treatment of orthotopic hepatic tumor. The IFDG is designed rationally based on the core "S-D-A-D-S" NIR-II probe IRFEP modified with folic acid (FA) for active tumor targeting and Gd-DOTA agent for MR imaging. The IFDG exhibits several advantages, including efficient tumor tissue accumulation, good tumor margin imaging effect, and excellent photothermal conversion effect. Therefore, the IFDG could realize accurate long-term monitoring and photothermal therapy non-invasively of the hepatic tumor to reduce its size. Next, the complete resection of the hepatic tumor in situ lesions could be realized by the intraoperative real-time NIR-II imaging guidance. Notably, the preoperative downstaging strategy is confirmed to lower the postoperative recurrence rate of the liver cancer patients under middle and advanced stage effectively with fewer side effects. Overall, the designed nanoplatform demonstrates great potential as a diagnostic-therapeutic integration platform for precise imaging-guided surgical navigation of orthotopic hepatic tumors with a low recurrence rate after surgery, providing a paradigm for diagnosing and treating the advanced tumors in the future clinical translation application.

Synthesis of germanium/germanium phosphide in-plane heterostructure with efficient photothermal and enhanced photodynamic effects in the second near-infrared biowindow

Inspired by the bifunctional phototherapy agents (PTAs), constructing compact PTAs with efficient photothermal therapy (PTT) and photodynamic therapy (PDT) effects in the near-infrared (NIR-II) biowindow is crucial for high therapeutic efficacy. Herein, none-layered germanium (Ge) is transformed to layered Ge/germanium phosphide (Ge/GeP) structure, and a novel two-dimensional sheet-like compact S-scheme Ge/GeP in-plane heterostructure with a large extinction coefficient of 15.66 L/g cm-1 at 1,064 nm is designed and demonstrated. In addition to the outstanding photothermal effects, biocompatibility and degradability, type I and type II PDT effects are activated by a single laser. Furthermore, enhanced reactive oxygen species generation under longer wavelength NIR laser irradiation is achieved, and production of singlet oxygen and superoxide radical upon 1,064 nm laser irradiation is more than double that under 660 nm laser irradiation. The S-scheme charge transfer mechanism between Ge and GeP, is demonstrated by photo-irradiated Kelvin probe force microscopy and electron spin resonance analysis. Thus, the obtained S-scheme Ge/GeP in-plane heterostructure shows synergistic therapeutic effects of PTT/PDT both in vitro and in vivo in the NIR-II biowindow and the novel nanoplatform with excellent properties has large clinical potential.

A dipyridophenazine Ni(II) dithiolene complex as a dual-acting cancer phototherapy agent activatable within the phototherapeutic window

A combination of photodynamic therapy (PDT) and photothermal therapy (PTT) within the phototherapeutic window (600-900 nm) can lead to significantly enhanced therapeutic outcomes, surpassing the efficacy observed with PDT or PTT alone in cancer phototherapy. Herein, we report a novel small-molecule mixed-ligand Ni(II)-dithiolene complex (Ni-TDD) with a dipyridophenazine ligand, demonstrating potent red-light PDT and significant near-infrared (NIR) light mild-temperature PTT activity against cancer cells and 3D multicellular tumour spheroids (MCTSs). The four-coordinate square planar complex exhibited a moderately intense absorption band (ε ∼ 3700 M-1cm-1) centered around 900 nm and demonstrated excellent dark and photostability in an aqueous phase. Ni-TDD induced a potent red-light (600-720 nm) PDT effect on HeLa cancer cells (IC50 = 1.8 μM, photo irritation factor = 44), triggering apoptotic cell death through efficient singlet oxygen generation. Ni-TDD showed a significant intercalative binding affinity towards double-helical calf thymus DNA, resulting in a binding constant (Kb) ∼ 106 M-1. The complex induced mild hyperthermia and exerted a significant mild-temperature PTT effect on MDA-MB-231 cancer cells upon irradiation with 808 nm NIR light. Simultaneous irradiation of Ni-TDD-treated HeLa MCTSs with red and NIR light led to a remarkable synergistic inhibition of growth, exceeding the effects of individual irradiation, through the generation of singlet oxygen and mild hyperthermia. Ni-TDD displayed minimal toxicity towards non-cancerous HPL1D and L929 cells, even at high micromolar concentrations. This is the first report of a Ni(II) complex demonstrating red-light PDT activity and the first example of a first-row transition metal complex exhibiting combined PDT and PTT effects within the clinically relevant phototherapeutic window. Our findings pave the way for designing and developing metal-dithiolene complexes as dual-acting cancer phototherapy agents using long wavelength light for treating solid tumors.

Functionalized MoS2-nanosheets with NIR-Triggered nitric oxide delivery and photothermal activities for synergistic antibacterial and regeneration-promoting therapy

Bacterial infection in skin and soft tissue has emerged as a critical concern. Overreliance on antibiotic therapy has led to numerous challenges, including the emergence of multidrug-resistant bacteria and adverse drug reactions. It is imperative to develop non-antibiotic treatment strategies that not only exhibit potent antibacterial properties but also promote rapid wound healing and demonstrate biocompatibility. Herein, a novel multimodal synergistic antibacterial system (SNO-CS@MoS2) was developed. This system employs easily surface-modified thin-layer MoS2 as photothermal agents and loaded with S-nitrosothiol-modified chitosan (SNO-CS) via electrostatic interactions, thus realizing the combination of NO gas therapy and photothermal therapy (PTT). Furthermore, this surface modification renders SNO-CS@MoS2 highly stable and capable of binding with bacteria. Through PTT's thermal energy, SNO-CS@MoS2 rapidly generates massive NO, collaborating with PTT to achieve antibacterial effects. This synergistic therapy can swiftly disrupt the bacterial membrane, causing protein leakage and ATP synthesis function damage, ultimately eliminating bacteria. Notably, after effectively eliminating all bacteria, the residual SNO-CS@MoS2 can create trace NO to promote fibroblast migration, proliferation, and vascular regeneration, thereby accelerating wound healing. This study concluded that SNO-CS@MoS2, a novel multifunctional nanomaterial with outstanding antibacterial characteristics and potential to promote wound healing, has promising applications in infected soft tissue wound treatment.

Mn-single-atom nano-multizyme enabled NIR-II photoacoustically monitored, photothermally enhanced ROS storm for combined cancer therapy

RATIONALE

To realize imaging-guided multi-modality cancer therapy with minimal side effects remains highly challenging.

METHODS

We devised a bioinspired hollow nitrogen-doped carbon sphere anchored with individually dispersed Mn atoms (Mn/N-HCN) via oxidation polymerization with triton micelle as a soft template, followed by carbonization and annealing. Enzyme kinetic analysis and optical properties were performed to evaluate the imaging-guided photothermally synergized nanocatalytic therapy.

RESULTS

Simultaneously mimicking several natural enzymes, namely peroxidase (POD), catalase (CAT), oxidase (OXD), and glutathione peroxidase (GPx), this nano-multizyme is able to produce highly cytotoxic hydroxyl radical (•OH) and singlet oxygen (1O2) without external energy input through parallel and series catalytic reactions and suppress the upregulated antioxidant (glutathione) in tumor. Furthermore, NIR-II absorbing Mn/N-HCN permits photothermal therapy (PTT), enhancement of CAT activity, and photoacoustic (PA) imaging to monitor the accumulation kinetics of the nanozyme and catalytic process in situ. Both in vitro and in vivo experiments demonstrate that near-infrared-II (NIR-II) PA-imaging guided, photothermally enhanced and synergized nanocatalytic therapy is efficient to induce apoptosis of cancerous cells and eradicate tumor tissue.

CONCLUSIONS

This study not only demonstrates a new method for effective cancer diagnosis and therapy but also provides new insights into designing multi-functional nanozymes.

Nano-modulators with the function of disrupting mitochondrial Ca2+ homeostasis and photothermal conversion for synergistic breast cancer therapy

Breast cancer treatment has been a global puzzle, and apoptosis strategies based on mitochondrial Ca2+ overload have attracted extensive attention. However, various limitations of current Ca2+ nanogenerators make it difficult to maintain effective Ca2+ overload concentrations. Here, we constructed a multimodal Ca2+ nano-modulator that, for the first time, combined photothermal therapy (PTT) and mitochondrial Ca2+ overload strategies to inhibit tumor development. By crosslinking sodium alginate (SA) on the surface of calcium carbonate (CaCO3) nanoparticles encapsulating with Cur and ICG, we prepared a synergistic Ca2+ nano-regulator SA/Cur@CaCO3-ICG (SCCI). In vitro studies have shown that SCCI further enhanced photostability while preserving the optical properties of ICG. After uptake by tumor cells, SCCI can reduce mitochondrial membrane potential and down-regulate ATP production by producing large amounts of Ca2+ at low pH. Near-infrared light radiation (NIR) laser irradiation made the tumor cells heat up sharply, which not only accelerated the decomposition of CaCO3, but also produced large amounts of reactive oxygen species (ROS) followed by cell apoptosis. In vivo studies have revealed that the Ca2+ nano-regulators had excellent targeting, biocompatibility, and anti-tumor effects, which can significantly inhibit the proliferation of tumor cells and play a direct killing effect. These findings indicated that therapeutic strategies based on ionic interference and PTT had great therapeutic potential, providing new insights into antitumor therapy.

Mild photothermal therapy assist in promoting bone repair: Related mechanism and materials

Achieving precision treatment in bone tissue engineering (BTE) remains a challenge. Photothermal therapy (PTT), as a form of precision therapy, has been extensively investigated for its safety and efficacy. It has demonstrated significant potential in the treatment of orthopedic diseases such as bone tumors, postoperative infections and osteoarthritis. However, the high temperatures associated with PTT can lead to certain limitations and drawbacks. In recent years, researchers have explored the use of biomaterials for mild photothermal therapy (MPT), which offers a promising approach for addressing these limitations. This review provides a comprehensive overview of the mechanisms underlying MPT and presents a compilation of photothermal agents and their utilization strategies for bone tissue repair. Additionally, the paper discusses the future prospects of MPT-assisted bone tissue regeneration, aiming to provide insights and recommendations for optimizing material design in this field.

Biomimetic theranostic nanoparticles for effective anticancer therapy and MRI imaging

Cancer remains a leading cause of mortality worldwide, necessitating the development of innovative therapeutic approaches. Nanoparticle-based drug delivery systems have garnered significant interest due to their multifunctionality, offering the potential to enhance cancer treatment efficacy and improve patient tolerability. Membrane-coated drug delivery systems hold great potential for enhancing the therapeutic outcome of nanoparticle-based anticancer therapies. In this study, we report the synthesis of multifunctional iron-functionalized mesoporous polydopamine nanoparticles (MPDAFe NPs). These nanoformulations demonstrate substantial potential for combining efficient drug delivery and magnetic resonance imaging (MRI) and showcase the advantages of biomimetic coating with tumor cell-derived membranes. This coating confers prolonged circulation and improved the targeting capabilities of the nanoparticles. Furthermore, comprehensive biosafety evaluations reveal negligible toxicity to normal cells, while the combined chemo- and phototherapy exhibited significant cytotoxicity towards cancer cells. Additionally, the photothermal effect evaluation highlights the enhanced cytotoxicity achieved through laser irradiation, showcasing the synergistic effects of the nanomaterials and photothermal therapy. Importantly, our chemotherapeutic effect evaluation demonstrates the superior efficacy of doxorubicin-loaded MPDAFe@Mem NPs (cancer cell membrane-coated MPDAFe NPs) in inhibiting cancer cell viability and proliferation, surpassing the potency of free doxorubicin. This study comprehensively investigates theranostic, membrane-coated drug delivery systems, underlining their potential to increase the efficacy of cancer treatment strategies. The multifunctional nature of the iron-functionalized polydopamine nanoparticles allows for efficient drug delivery and imaging capabilities, while the biomimetic coating enhances their biocompatibility and targeting ability. These findings contribute valuable insights towards the development of advanced nanomedicine for improved cancer therapeutics.

Photothermal hyaluronic acid composite hydrogel targeting cancer stem cells for inhibiting recurrence and metastasis of breast cancer

Recurrence and metastasis have been recognized as a great challenge in cancer treatment. Cancer stem cells (CSCs), as a small subset of cancer cells, are closely associated with tumor metastasis and recurrence due to their resistance and multi-differentiation characteristics. Herein, we developed a local injectable hyaluronic acid (HA) composite hydrogel (HAAG) that targets CSCs, which can continuously release all-trans retinoic acid (ATRA) and gold nanoparticles (AuNPs) at tumor sites. The composite hydrogel was endowed with the ability to target CSCs through the specific binding of HA to CD44. ATRA was loaded into HA micelles to induce CSCs to differentiate into normal cancer cells, while AuNPs was incorporated into the hydrogel for photothermal therapy (PTT). HAAG exhibited good injectability, photothermal properties and CSCs targeting ability. HAAG not only significantly inhibited the growth of 4T1 mouse breast cancer cells and 4T1-CSCs in vitro, but also effectively inhibited tumor recurrence and metastasis in a 4T1-CSC mouse model in vivo. Our study provides a novel strategy of local differentiation combined with PTT for inhibiting the recurrence and metastasis of breast cancer.

Photochemical outcomes triggered by gold shell-isolated nanorods on bioinspired nanoarchitectonics for bacterial membranes

Boosted by the indiscriminate use of antibiotics, multidrug-resistance (MDR) demands new strategies to combat bacterial infections, such as photothermal therapy (PTT) based on plasmonic nanostructures. PTT efficiency relies on photoinduced damage caused to the bacterial machinery, for which nanostructure incorporation into the cell envelope is key. Herein, we shall unveil the binding and photochemical mechanisms of gold shell-isolated nanorods (AuSHINRs) on bioinspired bacterial membranes assembled as Langmuir and Langmuir-Schaefer (LS) monolayers of DOPE, Lysyl-PG, DOPG and CL. AuSHINRs incorporation expanded the isotherms, with stronger effect on the anionic DOPG and CL. Indeed, FTIR of LS films revealed more modifications for DOPG and CL owing to stronger attractive electrostatic interactions between anionic phosphates and the positively charged AuSHINRs, while electrostatic repulsions with the cationic ethanolamine (DOPE) and lysyl (Lysyl-PG) polar groups might have weakened their interactions with AuSHINRs. No statistical difference was observed in the surface area of irradiated DOPE and Lysyl-PG monolayers on AuSHINRs, which is evidence of the restricted nanostructures insertion. In contrast, irradiated DOPG monolayer on AuSHINRs decreased 4.0 % in surface area, while irradiated CL monolayer increased 3.7 %. Such results agree with oxidative reactions prompted by ROS generated by AuSHINRs photoactivation. The deepest AuSHINRs insertion into DOPG may have favored chain cleavage while hydroperoxidation is the mostly like outcome in CL, where AuSHINRs are surrounding the polar groups. Furthermore, preliminary experiments on Escherichia coli culture demonstrated that the electrostatic interactions with AuSHINRs do not inhibit bacterial growth, but the photoinduced effects are highly toxic, resulting in microbial inactivation.

A nanoparticle composed of totally hospital-available drugs and isotope for fluorescence/SPECT dual-modal imaging-guided photothermal therapy to inhibit tumor metastasis

As primary sites of tumor metastasis, sentinel lymph nodes (SLNs) require a highly biocompatible theranostic platform for precise localization and treatment to inhibit tumor metastasis. Herein, indocyanine green-human serum albumin (ICG-HSA) nanoparticles (NPs) were fabricated by ICG-induced self-assembly and radiolabeled with technetuim-99 m (99mTc). The fabricated NPs were composed of hospital-available drugs and isotopes, making them highly biocompatible for in vivo applications. In a mouse model of SLN metastasis, the prepared NPs exhibited excellent capacity for preoperative planning by single-photon emission computed tomography (SPECT) imaging-enabled SLN localization, near-infrared fluorescence (NIRF) imaging-enabled intraoperative real-time monitoring, and SLN photothermal treatment. Photothermal treatment with SLN enhanced the inhibition of lung metastasis and significantly increased the survival time of mice. The prepared NPs were highly biocompatible and exhibited efficient theranostic properties for inhibiting cancer metastasis, making them promising candidates for clinical translation.

Glucose-responsive enzymatic biomimetic nanodots for H2O2 self-supplied catalytic photothermal/chemodynamic anticancer therapy

Photothermal therapy (PTT) combined with chemodynamic therapy (CDT) presents an appealing complementary anti-tumor strategy, wherein PTT accelerates the production of reactive oxygen species (ROS) in CDT and CDT eliminates residual tumor tissues that survive from PTT treatment. However, nanomaterials utilized in PTT/CDT are limited by non-specific damage to the entire organism. Herein, a glucose-responsive enzymatic Fe@HRP-ABTS/GOx nanodot is judiciously designed for tumor-specific PTT/CDT via a simple and clean protein-templated biomimetic mineralization synthesis. By oxidizing glucose in tumor cells, glucose oxidase (GOx) activates glucose-responsive tumor therapy and increases the concentration of H2O2 at the tumor site. More importantly, the self-supplied peroxide hydrogen (H2O2) can convert ABTS (2,2'-Hydrazine-bis(3-ethylbenzothiazoline-6-sulfonic acid) diamine salt) into oxidized ABTS (oxABTS) through horseradish peroxidase (HRP) catalysis for PTT and photoacoustic (PA) imaging. Furthermore, the Fe2+ arising from the reduction of Fe3+ by overexpressed GSH reacts with H2O2 to generate intensely reactive •OH through the Fenton reaction, concurrently depleting GSH and inducing efficient tumor CDT. The in vitro and in vivo experiments demonstrate superior cancer cell killing and tumor eradication effect of Fe@HRP-ABTS/GOx nanodot under near-infrared (NIR) laser irradiation. Collectively, the nanodots provide mutually reinforcing catalytic PTT/CDT anti-tumor strategies for treating liver cancer and potentially other malignancies. STATEMENT OF SIGNIFICANCE: Combinatorial antitumor therapy with nanomedicines presents great prospects for development. However, the limitation of non-specific damage to normal tissues hinders its further clinical application. In this work, we fabricated tumor-selective biomimetic Fe@HRP-ABTS/GOx nanodots for H2O2 self-supplied catalytic photothermal/chemodynamic therapy of tumors. The biomimetic synthesis strategy provides the nanodots with enzymatic activity in response to glucose to produce H2O2. The self-supplied H2O2 initiates photothermal therapy with oxidized ABTS and enhances chemodynamic therapy through simultaneous •OH generation and GSH depletion. Our work provides a new paradigm for developing tumor-selective catalytic nanomedicines and will guide further clinical translation of the enzymatic biomimetic synthesis strategy.

Iridium nanozyme-mediated photoacoustic imaging-guided NIR-II photothermal therapy and tumor microenvironment regulation for targeted eradication of cancer stem cells

Cancer stem cells (CSCs) are found in many solid tumors, which play decisive roles in the occurrence, recurrence and metastasis of tumors. However, drugs are difficult to kill CSCs due to their limited number and location in oxygen-deprived tissue far from the blood vessels. Meanwhile, the survival and stemness maintenance of CSCs strongly depend on the tumor microenvironment (TME). Herein, we developed a CD44 antibody modified iridium nanosheet with enzyme-like activity (defined as Ir Nts-Ab) that effectively eradicates CSCs for cancer therapy. We observe that Ir Nts-Ab can enrich tumor tissues to remove excessive reactive oxygen species and produce oxygen, thus alleviating hypoxia and the inflammatory TME to reduce the proportion of CSCs and inhibit metastasis. In addition, Ir Nts-Ab targets CSCs and normal cancer cells with near infrared II-region photothermal therapy (NIR-II PTT), and is easily taken up by CSCs due to recognition of the CD44 proteins. Moreover, photoacoustic imaging helps monitor drug accumulation and hypoxic TME improvement in tumor tissue. Importantly, Ir Nts-Ab has good biological safety, making it suitable for biomedical applications. This iridium nanozyme based on TME regulation as well as NIR-II PTT will be a promising strategy for the treatment of cancer. STATEMENT OF SIGNIFICANCE: Cancer stem cells (CSCs) are key factors that make tumors difficult to eradicate, and strongly depend on the hypoxic tumor microenvironment (TME), which plays a crucial role in the occurrence and metastasis of tumors. Herein, an antibody modified iridium nanosheet (definition as Ir Nts-Ab) was developed for targeted eradication of CSCs by photoacoustic imaging guided photothermal therapy (PTT) and TME regulation. Ir Nts-Ab with catalase-like activity could inhibit HIF-1α by producing oxygen, thus effectively reducing the proportion of CSCs and inhibiting tumor metastasis. Additionally, Ir Nts-Ab achieved the eradication of CSCs by PTT, and eliminated reactive oxygen species to decrease the inflammatory response, resulting in reduced tumor metastasis, which was promising for the cure of solid tumors in the clinics.

Synergized photothermal therapy and magnetic field induced hyperthermia via bismuthene for lung cancer combinatorial treatment

Thanks to its intrinsic properties, two-dimensional (2D) bismuth (bismuthene) can serve as a multimodal nanotherapeutic agent for lung cancer acting through multiple mechanisms, including photothermal therapy (PTT), magnetic field-induced hyperthermia (MH), immunogenic cell death (ICD), and ferroptosis. To investigate this possibility, we synthesized bismuthene from the exfoliation of 3D layered bismuth, prepared through a facile method that we developed involving surfactant-assisted chemical reduction, with a specific focus on improving its magnetic properties. The bismuthene nanosheets showed high in vitro and in vivo anti-cancer activity after simultaneous light and magnetic field exposure in lung adenocarcinoma cells. Only when light and magnetic field are applied together, we can achieve the highest anti-cancer activity compared to the single treatment groups. We have further shown that ICD-dependent mechanisms were involved during this combinatorial treatment strategy. Beyond ICD, bismuthene-based PTT and MH also resulted in an increase in ferroptosis mechanisms both in vitro and in vivo, in addition to apoptotic pathways. Finally, hemolysis in human whole blood and a wide variety of assays in human peripheral blood mononuclear cells indicated that the bismuthene nanosheets were biocompatible and did not alter immune function. These results showed that bismuthene has the potential to serve as a biocompatible platform that can arm multiple therapeutic approaches against lung cancer.

IOX1 epigenetically enhanced photothermal therapy of 3D-printing silicene scaffolds against osteosarcoma with favorable bone regeneration

Osteosarcoma (OS) is the third most common malignancy in adolescence. Currently, the treatments of OS confront great obstacles of tumor recurrence and critical bone defects after surgery, severely affecting the survival rates and living qualities of patients. Hence, it is urged to develop distinct biomaterials with both efficient tumor therapeutic and osteogenic functions. Although photothermal therapy (PTT) has aroused expanding interest, characterizing negligible invasiveness and high spatiotemporal adjustment, few studies discussed its drawbacks, such as thermal injury to adjacent normal tissue and exceeded laser power density, implying that focusing on sensitizing OS to PTT instead of simply elevating the laser power density may be a fresh way to enhance the PTT efficacy and attenuate the side/adverse effects. Herein, we successfully constructed 3D-printing silicene bioactive glass scaffolds with preferable PTT efficacy at the second near-infrared (NIR-II) biowindow and outstanding osteogenic biofunctions owing to the release of bioactive elements during degradation. Impressively, a histone demethylase inhibitor, IOX1, was introduced before PTT to sensitize OS to thermal therapy and minimize the side/adverse effects. This work offered a distinctive paradigm for optimizing the PTT efficacy of osteogenic scaffolds against OS with epigenetic modulation agents.

HER2-targeting two-dimensional black phosphorus as a nanoplatform for chemo-photothermal therapy in breast cancer

Trastuzumab (Tmab) targeted therapy or its combination with chemotherapy is normally insufficient to elicit a comprehensive therapeutic response owing to the inherent or acquired drug resistance and systemic toxicity observed in highly invasive HER2-positive breast cancer. In this study, we propose a novel approach that integrates photothermal therapy (PTT) with targeted therapy and chemotherapy, thereby achieving additive or synergistic therapeutic outcomes. We utilize PEGylated two-dimensional black phosphorus (2D BP) as a nanoplatform and photothermal agent to load chemotherapeutic drug mitoxantrone (MTO) and conjugate with Tmab (BP-PEG-MTO-Tmab). The in vitro and in vivo experiments demonstrated that the HER2-targeting BP-PEG-MTO-Tmab complexes exhibited desirable biocompatibility, safety and enhanced cancer cell uptake efficiency, resulting in increased accumulation and prolonged retention of BP and MTO within tumors. Consequently, the complex improved photothermal and chemotherapy treatment efficacy in HER2-positive cells in vitro and a subcutaneous tumor model in vivo, while minimized harm to normal cells and showed desirable organ compatibility. Collectively, our study provides compelling evidence for the remarkable efficacy of targeted and synergistic chemo-photothermal therapy utilizing all-in-one nanoparticles as a delivery system for BP and chemotherapeutic drug in HER2-positive breast cancer.

A multi-functional drug delivery nanosystem release of TLR-7 immunostimulant and OKT3 induced efficient cancer immunotherapy

Immunotherapy has some shortcomings such as off-target toxicity, treatment time and poor immunogenicity, which limit its therapeutic effect. Nanomaterials are particularly attractive in immunotherapy due to their drug delivery capabilities. Nano drug delivery system loaded with Toll-like receptor (TLR) agonist imiquimod (IMQ) and CD3 immune antibody OKT3 is constructed by using polydopamine (PDA) and CaCO3. While PDA-IMQ@CaCO3-OKT3 (PICO NPs) drug delivery system has the advantages of high biocompatibility, low toxicity, degradability. Antitumor studies in vitro and in vivo have shown that the system can effectively inhibit the proliferation of mouse breast cancer cells and the activity of Regulatory T Cells (Tregs), activate immunogenic cell death (ICD), and enhance the activity of antigen-presenting cells (APCs). Effectively eliminate tumor immunosuppression and fully activate immune function.

Phototherapy techniques for the management of musculoskeletal disorders: strategies and recent advances

Musculoskeletal disorders (MSDs), which include a range of pathologies affecting bones, cartilage, muscles, tendons, and ligaments, account for a significant portion of the global burden of disease. While pharmaceutical and surgical interventions represent conventional approaches for treating MSDs, their efficacy is constrained and frequently accompanied by adverse reactions. Considering the rising incidence of MSDs, there is an urgent demand for effective treatment modalities to alter the current landscape. Phototherapy, as a controllable and non-invasive technique, has been shown to directly regulate bone, cartilage, and muscle regeneration by modulating cellular behavior. Moreover, phototherapy presents controlled ablation of tumor cells, bacteria, and aberrantly activated inflammatory cells, demonstrating therapeutic potential in conditions such as bone tumors, bone infection, and arthritis. By constructing light-responsive nanosystems, controlled drug delivery can be achieved to enable precise treatment of MSDs. Notably, various phototherapy nanoplatforms with integrated imaging capabilities have been utilized for early diagnosis, guided therapy, and prognostic assessment of MSDs, further improving the management of these disorders. This review provides a comprehensive overview of the strategies and recent advances in the application of phototherapy for the treatment of MSDs, discusses the challenges and prospects of phototherapy, and aims to promote further research and application of phototherapy techniques.

Photothermal therapy of copper incorporated nanomaterials for biomedicine

Studies have reported on the significance of copper incorporated nanomaterials (CINMs) in cancer theranostics and tissue regeneration. Given their unique physicochemical properties and tunable nanostructures, CINMs are used in photothermal therapy (PTT) and photothermal-derived combination therapies. They have the potential to overcome the challenges of unsatisfactory efficacy of conventional therapies in an efficient and non-invasive manner. This review summarizes the recent advances in CINMs-based PTT in biomedicine. First, the classification and structure of CINMs are introduced. CINMs-based PTT combination therapy in tumors and PTT guided by multiple imaging modalities are then reviewed. Various representative designs of CINMs-based PTT in bone, skin and other organs are presented. Furthermore, the biosafety of CINMs is discussed. Finally, this analysis delves into the current challenges that researchers face and offers an optimistic outlook on the prospects of clinical translational research in this field. This review aims at elucidating on the applications of CINMs-based PTT and derived combination therapies in biomedicine to encourage future design and clinical translation.

Macrophage membrane-encapsulated nitrogen-doped carbon quantum dot nanosystem for targeted treatment of Alzheimer's disease: Regulating metal ion homeostasis and photothermal removal of β-amyloid

The abnormal aggregation of β-amyloid protein (Aβ) is a major contributor to Alzheimer's disease (AD). Cu2+ homeostasis imbalance can lead to the aggregation of Aβ, resulting in cytotoxic oligomers and fibrous aggregates, causing neuroinflammation and nerve cell damage, ultimately leading to AD. In this study, we synthesized nitrogen-doped carbon quantum dot (CQD), and designed a macrophage membrane (RAW-M) encapsulated CQD nanosystem for the first time. The abundant nitrogen-containing groups on the surface of CQD effectively capture excess Cu2+ and inhibit rapid Aβ aggregation. Additionally, the good photothermal properties of CQD dissolve the formed fiber precipitates under near-infrared light (NIR). In vitro and in vivo studies showed that the nanosystem significantly improved BBB permeability under laser irradiation, enhancing its ability to cross the BBB and overcome traditional anti-AD drug limitations. In vivo investigations conducted on APP/PS1 mice indicate that the nanosystem strongly reduced Aβ deposition, mitigated neuroinflammation, and ameliorates deficits in learning and memory. Overall, our nanocarrier approach adjusts metal ion homeostasis, inhibits abnormal Aβ aggregation, and uses excellent photothermal properties to depolymerize mature Aβ fibrils to protect cells from Aβ neurotoxicity, providing an effective strategy for Aβ-targeted treatment of AD.

Application of advanced biomaterials in photothermal therapy for malignant bone tumors

Malignant bone tumors are characterized by severe disability rate, mortality rate, and heavy recurrence rate owing to the complex pathogenesis and insidious disease progression, which seriously affect the terminal quality of patients' lives. Photothermal therapy (PTT) has emerged as an attractive adjunctive treatment offering prominent hyperthermal therapeutic effects to enhance the effectiveness of surgical treatment and avoid recurrence. Simultaneously, various advanced biomaterials with photothermal capacity are currently created to address malignant bone tumors, performing distinctive biological functions, including nanomaterials, bioceramics (BC), polymers, and hydrogels et al. Furthermore, PTT-related combination therapeutic strategies can provide more significant curative benefits by reducing drug toxicity, improving tumor-killing efficiency, stimulating anti-cancer immunity, and improving immune sensitivity relative to monotherapy, even in complex tumor microenvironments (TME). This review summarizes the current advanced biomaterials applicable in PTT and relevant combination therapies on malignant bone tumors for the first time. The multiple choices of advanced biomaterials, treatment methods, and new prospects for future research in treating malignant bone tumors with PTT are generalized to provide guidance. Malignant bone tumors seriously affect the terminal quality of patients' lives. Photothermal therapy (PTT) has emerged as an attractive adjunctive treatment enhancing the effectiveness of surgical treatment and avoiding recurrence. In this review, advanced biomaterials applicable in the PTT of malignant bone tumors and their distinctive biological functions are comprehensively summarized for the first time. Simultaneously, multiple PTT-related combination therapeutic strategies are classified to optimize practical clinical issues, contributing to the selection of biomaterials, therapeutic alternatives, and research perspectives for the adjuvant treatment of malignant bone tumors with PTT in the future.

Cobalt-doped hollow polydopamine for oxygen generation and GSH consumption enhanced chemo-PTT combined cancer therapy

Nanotechnology has revolutionized the field of therapeutics by introducing a plethora of nanomaterials capable of enhancing traditional drug efficacy or paving the way for innovative treatment methods. Within this domain, we propose a novel Cobalt-doped hollow polydopamine nanosphere system. This system, incorporating Doxorubicin loading and hyaluronic acid (HA) surface coating (CoHPDA@DOX-HA), is designed for combined tumor therapy. The overarching aim is to diminish the administration dosage, mitigate the cytotoxic side effects of chemotherapy drugs, augment chemosensitivity within neoplastic tissues, and attain superior results in tumor treatment via combined therapeutic strategies. The targeted molecule, hyaluronic acid (HA), amplifies the biocompatibility of CoHPDA@DOX-HA throughout circulation and fosters endocytosis of the nanoparticle system within cancer cells. This nanosphere system possesses pH sensitivity properties, allowing for a meticulous drug release within the acidic microenvironment of tumor cells. Concurrently, Polydopamine (PDA) facilitates proficient photothermal therapy upon exposure to 808 nm laser irradiation. This process further amplifies the Glutathione (GSH) depletion, and when coupled with the oxygen production capabilities of the Cobalt-doped hollow PDA, significantly enhances the chemo-photothermal therapeutic efficiency. Findings from the treatment of tumor-bearing mice substantiate that even at dosages equivalent to a singular DOX administration, the CoHPDA@DOX-HA can provide efficacious synergistic therapy. Therefore, it is anticipated that multifunctional nanomaterials with Photoacoustic Tomography (PAT) imaging capabilities, targeted delivery, and a controlled collaborative therapeutic framework may serve as promising alternatives for accurate diagnostics and efficacious treatment strategies.

Photothermal Conversion of Hydrogel-Based Biomaterial

Traditional energy from fossil fuels like petroleum and coal is limited and contributes to global environmental pollution and climate change. Developing sustainable and eco-friendly energy is crucial for addressing significant challenges such as climate change, energy dilemma and achieving the long-term development of human society. Biomass hydrogels, which are easily synthesized and modified, have diverse sources and can be designed for different applications. They are being extensively researched for their applications in artificial intelligence, flexible sensing, biomedicine, and food packaging. The article summarizes recent advances in the preparation and applications of biomass-based photothermal conversion hydrogels, discussing the light source, photothermal agents, matrix, and preparation methods in detail. It also explores the use of these hydrogels in seawater desalination, photothermal therapy, antibacterial agents, and light-activated materials, offering new ideas for developing sustainable, efficient, and advanced photothermal conversion biomass hydrogel materials. The article concludes with suggestions for future research, highlighting the challenges and prospects in this field and paving the way for developing of long-lasting, efficient energy materials.

Fluoride releasing photothermal responsive TiO2 matrices for antibiosis, biosealing and bone regeneration

Peri-implantitis induced by infection leads to gingival recession, alveolar resorption and eventual dental implant failure. So, antibiosis and biosealing of abutments as well as osseointegration of roots need to be projected seriously during the whole service lifespan of dental implants. In this work, a multipurpose photothermal therapy strategy based on Si/P/F doped TiO2 matrix is proposed to address the above issues. This TiO2 matrix not only has outstanding photothermal response, but also triggers the release of F ions under near-infrared (NIR) light irradiation. Local hyperthermia assisted with the released F ions reduces adenosine triphosphate (ATP) synthesis of staphylococcus aureus (S. aureus), increases bacterial membrane permeability, and induces abundant of reactive oxygen species, resulting in the oxidation of cellular components and eventual death of bacteria. Furthermore, the synergic action of mild photothermal stimulation and Si/P/F ions of TiO2 matrix up-regulates gingival epithelial cells behavior (e.g., hemidesmosome formation) and osteoblasts response in vitro. In an infected model, this TiO2 matrix obviously eliminates bacteria, reduces inflammatory response, improves epithelial sealing and osseointegration, and reduces alveolar resorption by regulating NIR irradiation.

Nanoarchitecture-based photothermal ablation of cancer: A systematic review

Photothermal therapy (PTT) is an emerging non-invasive method used in cancer treatment. In PTT, near-infrared laser light is absorbed by a chromophore and converted into heat within the tumor tissue. PTT for cancer usually combines a variety of interactive plasmonic nanomaterials with laser irradiation. PTT enjoys PT agents with high conversion efficiency to convert light into heat to destroy malignant tissue. In this review, published studies concerned with the use of nanoparticles (NPs) in PTT were collected by a systematic and comprehensive search of PubMed, Cochrane, Embase, and Scopus databases. Gold, silver and iron NPs were the most frequent choice in PTT. The use of surface modified NPs allowed selective delivery and led to a precise controlled increase in the local temperature. The presence of NPs during PTT can increase the reactive generation of oxygen species, damage the DNA and mitochondria, leading to cancer cell death mainly via apoptosis. Many studies recently used core-shell metal NPs, and the effects of the polymer coating or ligands targeted to specific cellular receptors in order to increase PTT efficiency were often reported. The effective parameters (NP type, size, concentration, coated polymers or attached ligands, exposure conditions, cell line or type, and cell death mechanisms) were investigated individually. With the advances in chemical synthesis technology, NPs with different shapes, sizes, and coatings can be prepared with desirable properties, to achieve multimodal cancer treatment with precision and specificity.

Photothermal antibacterial materials to promote wound healing

Wound healing is a crucial process that restores the integrity and function of the skin and other tissues after injury. However, external factors, such as infection and inflammation, can impair wound healing and cause severe tissue damage. Therefore, developing new drugs or methods to promote wound healing is of great significance. Photothermal therapy (PTT) is a promising technique that uses photothermal agents (PTAs) to convert near-infrared radiation into heat, which can eliminate bacteria and stimulate tissue regeneration. PTT has the advantages of high efficiency, controllability, and low drug resistance. Hence, nanomaterial-based PTT and its related strategies have been widely explored for wound healing applications. However, a comprehensive review of PTT-related strategies for wound healing is still lacking. In this review, we introduce the physiological mechanisms and influencing factors of wound healing, and summarize the types of PTAs commonly used for wound healing. Then, we discuss the strategies for designing nanocomposites for multimodal combination treatment of wounds. Moreover, we review methods to improve the therapeutic efficacy of PTT for wound healing, such as selecting the appropriate wound dressing form, controlling drug release, and changing the infrared irradiation window. Finally, we address the challenges of PTT in wound healing and suggest future directions.

Amplification of oxidative damage using near-infrared II-mediated photothermal/thermocatalytic effects for periodontitis treatment

Periodontitis is a biofilm-related disease characterized by damage to the periodontal tissue and the development of systemic diseases. However, treatment of periodontitis remains unsatisfactory, especially with deep-tissue infections. This study describes rationally designed multifunctional photothermocatalytic agents for near-infrared-II light-mediated synergistic antibiofilm treatment, through modification of Lu-Bi2Te3 with Fe3O4 and poly(ethylene glycol)-b-poly(l-arginine) (PEG-b-PArg). Notably, 1064-nm laser irradiation led to photothermal/thermocatalytic effects, resulting in the synergistic generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) and consequent damage to the biofilm. This treatment was based on the thermoelectric and photothermal conversion properties of Lu-Bi2Te3, the peroxidase-like catalytic capacity of Fe3O4, and the guanidinium polymer, PEG-b-PArg. Oxidative damage to biofilm was further enhanced by H2O2, resulting in the effective elimination of biofilm both in vitro and in vivo. These findings suggest that this synergistic therapeutic strategy is effective for the clinical treatment of periodontitis. STATEMENT OF SIGNIFICANCE: The current treatment for periodontitis involves time-consuming and labor-intensive clinical scaling of the teeth. The present study is the first to assess the efficacy of a photothermal catalyst for periodontitis treatment. This used near-infrared-II light at 1064 nm to induce oxidative damage in the biofilm, resulting in its degradation. The synergistic photothermal/thermoelectric effect produced deep tissue penetration and was well tolerated, and can kill the biofilm formed by periodontitis pathogens up to 5 orders of magnitude, effectively treating the biofilm-induced periodontitis.

Nanoparticles for imaging-guided photothermal therapy of colorectal cancer

Colorectal cancer (CRC) is one of the most common malignancies with a high mortality rate worldwide. While surgery, chemotherapy, and radiotherapy have shown some effectiveness in improving survival rates, they come with drawbacks such as side effects and harm to healthy tissues. The theranostic approach, which integrates the processes of cancer diagnosis and treatment, can minimize biological side effects. Photothermal therapy (PTT) is an emerging treatment method that usages light-sensitive agents to generate heat at the tumor site and induce thermal erosion. The development of nanotechnology for CRC treatment using imaging-guided PTT has garnered significant. Nanoparticles with suitable physical and chemical properties can enhance the efficiency of cancer diagnosis and PTT. This approach enables the monitoring of cancer treatment progress and safeguards healthy tissues. In this article, we concisely introduce the application of metal nanoparticles, polymeric nanoparticles, and carbon nanoparticles in imaging-guided PTT of colorectal cancer.

Multifunctional bioactive glasses with spontaneous degradation for simultaneous osteosarcoma therapy and bone regeneration

For the treatment of tumor-related bone defects resulting from surgical resection, simultaneous eradication of residual tumor cells and repair of bone defects represent a challenge. To date, photothermal therapy based on photothermal materials is used to remove residual tumor cells under near infrared light. However, most of photothermal materials have no function for bone repair, and even if combined with bioactive materials to enhance osteogenesis, they still cause potential harm to the body due to inability to degrade or poor degradability. Herein, multifunctional bioactive glasses (PGFe5-1100, PGCu5-1100) based on phosphate glass doped with transition metal elements were prepared for photothermal ablation, bone regeneration, and controllable degradation. The glasses exhibited excellent photothermal effect, which was derived from the electron in-band transition after light absorption due to energy level splitting of doped transition metal element and the subsequent electron nonradiative relaxation. The photothermal performance can be controlled by laser power density, element doping content and glass melting temperature. Moreover, the hyperthermia induced by the glasses can effectively kill tumor cells in vitro. In addition, the glasses degraded over time, and the released P, Ca, Na, Fe could promote bone cell proliferation and osteogenic differentiation. Therefore, these results successfully demonstrated that transition metal element-doped phosphate glasses have multifunctional abilities of tumor elimination, bone regeneration, and spontaneous degradation simultaneously with better biosecurity and bioactivity, which is believed to pave the way for the design of novel biomaterials for osteosarcoma treatment.

Magnesium/gallic acid bioMOFs laden carbonized mushroom aerogel effectively heals biofilm-infected skin wounds

Biofilm-infected acute skin wounds are still one of the significant challenges that need to be solved urgently in wound healing. Herein, we reported a magnesium/gallic acid bio-MOFs laden carbonized mushroom aerogel (QMOFs-PCMA) combined with photothermal therapy for eradicating biofilms in skin wounds. The design of bioMOFs is mainly responsible for regulating immunity. In vitro, it exhibited ROS clearance and antioxidant ability. In vivo, it could regulate local immune responses from pro-inflammatory status to pro-regenerative status, resulting in decreased inflammatory cytokines expression and increased anti-inflammatory cytokines expression. The carbonized mushroom aerogel is mainly responsible for photothermal therapy (PTT), and the polydopamine and bioMOFs could enhance the photothermal conversion efficiency and stability of carbonized aerogels. The carbonized aerogel in combination with PTT could eradicate S. aureus biofilm in both in vitro and in vivo studies and clear E. coli biofilms in vitro studies. The biofilm clearance and improved inflammatory responses laid a good foundation for wound healing, resulting in the granulation tissue formation, re-epithelialization, and angiogenesis significantly enhanced in the QMOFs-PCMA + NIR group. Our results indicate that the QMOFs-PCMA combined with photothermal therapy may provide a promising treatment for biofilm-infected skin wounds.

A TiN-based nanophotosensitizer for enhanced photothermal therapy with the aid of ultrasound

BACKGROUND AND PURPOSE

Targeting and uptake are the most important strategies for enhancing the efficacy of cancer photothermal therapy (PTT) and reducing damage to surrounding normal tissues. In this study, a kind of nanophotosensitizer based on nanobubbles and TiN was prepared for synergetic therapy for hepatocellular carcinoma.

METHODS

The photothermal agent titanium nitride (TiN) was wrapped in nanobubbles by membrane hydration method and verified in cells and animals. CCK-8, cell death staining, and JC-1 were used to verify the pernicious effect of photothermal combined with Ultrasound Targeted Nanobubble Destruction (UTND) and then injected into animals through the tail vein to observe its photothermal effect and in vivo inhibitory effect. A hemolysis test and body weight change verified its safety.

RESULTS

The average diameter of the novel nanophotosensitizer was 300.3 ± 12.7 nm, with a consistent nanospheres morphology. The UTND technology was utilized to improve the penetration of TiN into tumor cells through the physical energy of ultrasound irradiation. The therapeutic effects of the synergistic therapy of UTND and PTT were verified in vitro and in vivo.

CONCLUSION

The research has established NBs@C3F8-TiN as a suitable ultrasound photothermal agent due to its appropriate size and efficient photothermal efficacy for visual photothermal therapy for HCC.

GM-CSF augmented the photothermal immunotherapeutic outcome of self-driving gold nanoparticles against a mouse CT-26 colon tumor model

BACKGROUND

Hypoxia is a frequent characteristic observed in solid tumors and is strongly associated with tumor metastasis, angiogenesis, and drug resistance. While the vasculature of hypoxic tumor tissues poses obstacles to the efficient administration of conventional drugs, it may prove advantageous in sustaining hyperthermia. Photothermal therapy (PTT) offers a promising treatment strategy that utilizes the activation of photosensitizers to produce heat, thus facilitating the selective ablation of tumor tissues.

METHOD

To enhance the accumulation of photothermal agents in tumor tissue and improve the effectiveness of PTT, we developed a self-propelled hybrid called Bif@PAu-NPs. This hybrid consists of polydopamine (PDA)-coated gold nanoparticles (Au-NPs) loaded onto the anaerobic Bifidobacterium infantis (Bif).

RESULTS

The Bif@PAu-NPs actively aggregated at the tumor site because the ability of Bif can target hypoxic regions, and PAu-NPs achieved precise PTT due to their high photothermal conversion efficiency (η = 67.8%). The tumor tissues were ablated by PTT, resulting in the release of antigens through immunogenic cell death (ICD), which stimulates an immune response. The inclusion of GM-CSF enhanced the immune response by recruiting dendritic cells and initiating long-term anti-tumor immunity.

CONCLUSION

The Bif@PAu-NPs hybrid effectively suppressed the growth of both primary tumors and re-challenged tumors. The utilization Bif@PAu-NPs in conjunction with GM-SCF exhibits great potential as a photothermal-immunotherapeutic strategy for precisely treating solid tumors. In this study, the bacterial Bif@PAu-NPs biohybrid is exploited the self-driving ability of anaerobic Bifidobacterium infantis to deliver polydopamine-modified gold nanoparticles to hypoxic region of tumor. Under irradiation with 808 nm NIR laser, the hybrid exerts precise photothermal therapy to stimulate the immune response, which is further enhanced by GM-CSF, leading to recruitment of dendritic cells and initiation of a long-term anti-tumor immunity remember to prevent tumor recurrence.

A photoactivatable and phenylboronic acid-functionalized nanoassembly for combating multidrug-resistant gram-negative bacteria and their biofilms

Background

Multidrug-resistant (MDR) gram-negative bacteria-related infectious diseases have caused an increase in the public health burden and mortality. Moreover, the formation of biofilms makes these bacteria difficult to control. Therefore, developing novel interventions to combat MDR gram-negative bacteria and their biofilms-related infections are urgently needed. The purpose of this study was to develop a multifunctional nanoassembly (IRNB) based on IR-780 and N, N'-di-sec-butyl-N, N'- dinitroso-1,4-phenylenediamine (BNN6) for synergistic effect on the infected wounds and subcutaneous abscesses caused by gram-negative bacteria.

Methods

The characterization and bacteria-targeting ability of IRNB were investigated. The bactericidal efficacy of IRNB against gram-negative bacteria and their biofilms was demonstrated by crystal violet staining assay, plate counting method and live/dead staining in vitro. The antibacterial efficiency of IRNB was examined on a subcutaneous abscess and cutaneous infected wound model in vivo. A cell counting kit-8 assay, Calcein/PI cytotoxicity assay, hemolysis assay and intravenous injection assay were performed to detect the biocompatibility of IRNB in vitro and in vivo.

Results

Herein, we successfully developed a multifunctional nanoassembly IRNB based on IR-780 and BNN6 for synergistic photothermal therapy (PTT), photodynamic therapy (PDT) and nitric oxide (NO) effect triggered by an 808 nm laser. This nanoassembly could accumulate specifically at the infected sites of MDR gram-negative bacteria and their biofilms via the covalent coupling effect. Upon irradiation with an 808 nm laser, IRNB was activated and produced both reactive oxygen species (ROS) and hyperthermia. The local hyperthermia could induce NO generation, which further reacted with ROS to generate ONOO-, leading to the enhancement of bactericidal efficacy. Furthermore, NO and ONOO- could disrupt the cell membrane, which converts bacteria to an extremely susceptible state and further enhances the photothermal effect. In this study, IRNB showed a superior photothermal-photodynamic-chemo (NO) synergistic therapeutic effect on the infected wounds and subcutaneous abscesses caused by gram-negative bacteria. This resulted in effective control of associated infections, relief of inflammation, promotion of re-epithelization and collagen deposition, and regulation of angiogenesis during wound healing. Moreover, IRNB exhibited excellent biocompatibility, both in vitro and in vivo.

Conclusions

The present research suggests that IRNB can be considered a promising alternative for treating infections caused by MDR gram-negative bacteria and their biofilms.

Injectable hydrogel nanoarchitectonics with near-infrared controlled drug delivery for in situ photothermal/endocrine synergistic endometriosis therapy

BACKGROUND

Endometriosis is a common gynecological disease in women of childbearing age. Commonly used treatment methods, such as endocrine and surgical therapies, display poor therapeutic effects with a high relapse probability. Thus, novel treatments for endometriosis are required.

METHODS

In our study, polydopamine (PDA), letrozole (LTZ), and agarose (AG) hydrogels were combined to construct an injectable hydrogel with near-infrared controlled drug delivery named LTZ-PDA@AG hydrogel for endometriosis treatment. The release of letrozole can be accurately controlled by the near-infrared light intensity, exposure duration, polydopamine concentration, and hydrogel composition. Meanwhile, we isolated endometrial stromal cells from endometrium in patients with endometriosis, and constructed the rats' model of endometriosis to verify the biological effects of LTZ-PDA@AG hydrogel.

RESULTS

Owing to the sufficiently deep penetration of near-infrared light, the LTZ-PDA@AG hydrogel displayed a high temperature increase for efficient photothermal therapy. In addition, high local temperatures can further enhance the diffusion and penetration of letrozole, thereby achieving excellent therapeutic effect in vivo. Importantly, the in vivo and vitro test demonstrated the capacity of the nanocomposite hydrogel for endocrine-photothermal synergistic therapy and the biocompatibility.

CONCLUSION

Our work proposes a novel concept for precision endometriosis therapy by photothermal-enhanced endocrine therapy for endometriosis, which is proposed for the first time for the treatment of endometriosis and demonstrates excellent potential for further clinical translation.

TRIAL REGISTRATION

Not applicable. LTZ-PDA@AG hydrogels were synthesized and displayed a high temperature increase for efficient photothermal therapy under NIR. The present study shows the capacity of the nanocomposite hydrogel for endocrine-photothermal synergistic therapy and the biocompatibility.

Injectable biocompatible nanocomposites of Prussian blue nanoparticles and bacterial cellulose as a safe and effective photothermal cancer therapy

Photothermal therapy (PTT) is a novel cancer treatment using a photoabsorber to cause hyperthermia to kill tumors by laser irradiation. Prussian blue nanoparticles (PB NPs) are considered as next-generation photothermal agents due to the facile synthesis and excellent absorption of near-infrared light. Although PB NPs demonstrate remarkable PTT capabilities, their clinical application is limited due to their systemic toxicity. Bacterial cellulose (BC) has been applied to various bio-applications based on its unique properties and biocompatibility. Herein, we design composites with PB NPs and BC as an injectable, highly biocompatible PTT agent (IBC-PB composites). Injectable bacterial cellulose (IBC) is produced through the trituration of BC, with PB NPs synthesized on the IBC surface to prepare IBC-PB composites. IBC-PB composites show in vitro and in vivo photothermal therapeutic effects similar to those of PB NPs but with significantly greater biocompatibility. Specifically, in vitro therapeutic index of IBC-PB composites is 26.5-fold higher than that of PB NPs. Furthermore, unlike PB NPs, IBC-PB composites exhibit no overt toxicity in mice as assessed by blood biochemical analysis and histological images. Hence, it is worth pursuing further research and development of IBC-PB composites as they hold promise as safe and efficacious PTT agents for clinical application.

Numerical study on optimization of quantitative treatment conditions for skin cancer photothermal therapy considering multiple blood vessels

BACKGROUND

In recent years, lasers have gained considerable attention as a potential treatment option in the medical field. Photothermal therapy, in particular, has been investigated as a technique to remove tumor tissue by leveraging photothermal effects. The method involves raising the temperature of the tumor tissue to destroy it and has primarily been studied for skin cancer treatment.

OBJECTIVE

This study aimed to simulate a skin layer with squamous cell carcinoma by using numerical modeling and investigate the effect of different numbers of blood vessels on the temperature distribution in the medium under conditions such as varied laser intensity and gold nanoparticle volume fraction.

METHODS

Optical properties of the light absorption enhancer were calculated using the discrete dipole approximation method, and the temperature and velocity distribution were computed using continuity, momentum, and energy equations.

RESULTS

Quantitative determination of the apoptotic variable was performed to evaluate the treatment effect for each case, and the treatment condition with the maximum treatment effect was identified. Laser intensity with optimal therapeutic effect was confirmed to be 0.13 W, 0.15 W, 0.18 W, and 0.24 W, depending on the number of vessels, respectively, and the volume fraction of injected GNRs was confirmed to be 10-6 for all vessel numbers.

CONCLUSION

The results of this study can serve as a guide for selecting appropriate treatment conditions when conducting photothermal therapy in the future.

Palladium-based multifunctional nanoparticles for combined chemodynamic/photothermal and calcium overload therapy of tumors

Due to the high mortality and incidence rates associated with tumors and the specificity of the tumor microenvironment (TME), it is difficult to achieve a complete cure for tumors using a single therapy. In this study, calcium carbonate-modified palladium hydride nanoparticles (PdH@CaCO3) were prepared and utilized for the combined treatment of tumors through chemodynamic therapy (CDT)/photothermal therapy (PTT) and calcium overload therapy. After entering tumor cells, PdH@CaCO3 releases calcium ions (Ca2+) and PdH once it reaches the TME due to the pH reactivity of the calcium carbonate coating. The mitochondrial membrane potential is lowered by the Ca2+, leading to irreversible cell damage. Meanwhile, PdH reacts with excessive hydrogen peroxide (H2O2) in the TME via the Fenton reaction, generating hydroxyl radicals (·OH). Moreover, PdH is an excellent photothermal agent that can kill tumor cells under laser irradiation, leading to significant anti-tumor effects. In vitro and in vivo studies have demonstrated that PdH@CaCO3 could combine CDT/PTT and calcium overload therapy, exhibiting great clinical potential in the treatment of tumors.

NIR light-driven pure organic Janus-like nanoparticles for thermophoresis-enhanced photothermal therapy

Photothermal therapy (PTT) represents a promising noninvasive tumor therapeutic modality, but the current strategies for enhancing photothermal effect have been mainly based on promoting thermal relaxation or suppressing radiative dissipation process of excited energy, leaving little room for further improvement in photothermal effect. Herein, as a proof of concept, we report the thermophoresis-enhanced photothermal effect with pure organic Janus-like nanoparticles (Janus-like NPs) for PTT. The Janus-like NPs are eccentrically loaded with compactly J-aggregated photothermal molecules (DMA-BDTO), which show red-shifted absorption wavelength and inhibited radiative decay as compared to individual molecules. Under NIR irradiation, the asymmetric heat generation at particle surface endows Janus-like NPs the active thermophoresis, which further increases collisions and converts kinetic energy into thermal energy, and Janus-like NPs exhibit significantly elevated temperature as compared to conventional NPs with homogenously distributed DMA-BDTO. Both in vitro and in vivo results confirm such thermophoresis-enhanced photothermal effect for improved PTT. Our new strategy of thermophoresis-enhanced photothermal effect shall open new insights for improving photothermal-related tumor therapy.

A sequential scheme including PTT and 2'3'-cGAMP/CQ-LP reveals the antitumor immune function of PTT through the type I interferon pathway

Photothermal therapy (PTT) is a promising antitumor treatment that is easy to implement, minimally invasive, and precisely controllable, and evokes strong antitumor immunity. We believe that a thorough elucidation of its underlying antitumor immune mechanisms would contribute to the rational design of combination treatments with other antitumor strategies and consequently potentiate clinical use. In this study, PTT using indocyanine green (ICG) induced STING-dependent type I interferon (IFN) production in macrophages (RAW264.7 and bone marrow-derived macrophages (BMDMs)), as proven by the use of a STING inhibitor (C178), and triggered STING-independent type I IFN generation in tumor cells (CT26 and 4T1), which was inhibited by DNase pretreatment. A novel liposome coloaded with the STING agonist 2'3'-cGAMP (cGAMP) and chloroquine (CQ) was constructed to achieve synergistic effect with PTT, in which CQ increased cGAMP entrapment efficiency and prevented STING degradation after IFN signaling activation. The sequential combination treatment caused a significant increase in tumor cell apoptosis, probably due to interferon stimulating gene products 15 and 54 (ISG15 and ISG 54), and achieved a more striking antitumor inhibition effect in the CT26 tumor model than the 4T1 model, likely due to higher STAT1 expression and consequently more intense IFN signal transduction. In the tumor microenvironment, the combination treatment increased infiltrating CD8+T cells (4-fold) and M1-like TAMs (10-fold), and decreased M-MDSCs (over 2-fold) and M2-like TAMs (over 4-fold). Above all, in-depth exploration of the antitumor mechanism of PTT provides guidance for selecting sensitive tumor models and designing reasonable clinical schemes.

Enhanced stability and photothermal efficiency of Indocyanine Green J-aggregates by nanoformulation with Calix[4]arene for photothermal therapy of cancers

Photothermal therapy (PTT) is a method of growing attention, owing to its controllable process, high efficiency and minimal side effect. Indocyanine Green (ICG) is as Food and Drug Administration (FDA) approved agent that stands on the frontline of further developments of PTT toward clinics. However, the applicability of ICG-mediated PTT is limited by the rapid in vivo clearance and photo-degradation of ICG. To improve those parameters, nanosized ICG-loaded nanoparticles (ICG-J/CX) were fabricated in this study by co-assembly of anionic ICG J-aggregates (ICG-J) with cationic tetraguanidinium calix[4]arene (CX). This very simple approach produces ICG-J/CX with a well-defined nanometer range size and a close to neutral charge. The nanoparticles demonstrate high photothermal conversion efficiency (PCE) and dramatically improved photostability, as compared with ICG. The in vitro cellular uptake and cytotoxicity studies further demonstrated that the ICG-J/CX nanoparticles enhance uptake and photothermal efficiency in comparison with ICG or non-formulated ICG-J, overall demonstrating that ICG-J/CX mediated photothermal therapy have significant potential for attaining cancer treatment.

Polymeric graphene oxide nanoparticles loaded with doxorubicin for combined photothermal and chemotherapy in triple negative breast cancer

Combining photothermal and chemotherapy is an emerging strategy for tumor irradiation in a minimally invasive manner, utilizing photothermal transduction agents and anticancer drugs. The present work developed a 2D carbon nanomaterial graphene oxide (GO)-based nanoplatform that converted to 3D colloidal spherical structures upon functionalization with an amphiphilic polymer mPEG-PLA (1, 0.5/1/2) and entrapped doxorubicin (Dox) physically. The Dox@GO(mPP) (1/0.5) NPs displayed the least particle size (161 nm), the highest stability with no aggregation, the highest Dox loading (6.3 %) and encapsulation efficiency (70 %). The therapeutic efficacy was determined in vitro and in vivo using murine (4 T1) and human triple-negative breast cancer cells (MDA-MB-231), and 4 T1-Luc-tumor bearing mouse models. The results demonstrated that the Dox@GO(mPP) (1/0.5) NPs treatment with laser (+L) (808 nm) was highly efficient in inducing apoptosis, cell cycle arrest (G2/M) phase, significant cytotoxicity, mitochondrial membrane depolarization, ROS generation, and photothermal effect leading to a higher proportion of cell death than free Dox, and Dox@GO(mPP) (1/0.5) NPs (-L). The anticancer studies in mice harboring the 4 T1-Luc tumor showed that combination of Dox@GO(mPP) (1/0.5) NPs (+L) effectively reduced tumor development and decreased lung metastasis. The developed nanoplatform could be a promising combination chemo-photothermal treatment option for triple-negative breast cancer.

Recent advances in fluorescence imaging-guided photothermal therapy and photodynamic therapy for cancer: From near-infrared-I to near-infrared-II

Phototherapy (including photothermal therapy, PTT; and photodynamic therapy, PDT) has been widely used for cancer treatment, but conventional PTT/PDT show limited therapeutic effects due to the lack of disease recognition ability. The integration of fluorescence imaging with PTT/PDT can reveal tumor locations in a real-time manner, holding great potential in early diagnosis and precision treatment of cancers. However, the traditional fluorescence imaging in the visible and near-infrared-I regions (VIS/NIR-I, 400-900 nm) might be interfered by the scattering and autofluorescence from tissues, leading to a low imaging resolution and high false positive rate. The deeper near-infrared-II (NIR-II, 1000-1700 nm) fluorescence imaging can address these interferences. Combining NIR-II fluorescence imaging with PTT/PDT can significantly improve the accuracy of tumor theranostics and minimize damages to normal tissues. This review summarized recent advances in tumor PTT/PDT and NIR-II fluorophores, especially discussed achievements, challenges and prospects around NIR-II fluorescence imaging-guided PTT/PDT for cancers.

Multifunctional nanoadjuvant-driven microenvironment modulation for enhanced photothermal immunotherapy in breast cancer

Intracellular redox imbalance, achieved by exploiting the tumor microenvironment (TME), has emerged as a promising strategy for cancer therapy. In this study, we developed a multifunctional nanoadjuvant, termed GITFe/Z-HA, by modified a metal-organic backbone Fe/ZIF-8 with hyaluronic acid (HA) targeting. The nanocarriers were loaded with glucose oxidase (Gox), neoindocyanine green (IR820) and tilazamine (TPZ). This design aimed to achieve a cascade reaction within tumor cells, mediated by Gox, Fe3+, and IR820, which consumes intrinsic glucose and oxygen, leading to an elevated production of reactive oxygen species (ROS). This cascade reaction creates a hypoxic environment conducive for TPZ to exert its therapeutic action. Consequently, the combination of photothermal therapy (PTT), photodynamic therapy (PDT), and chemotherapy demonstrates a good synergistic effect. Moreover, the imbalanced ROS/glutathione (GSH) induced by this treatment approach, along with PTT, promote immunogenic cell death (ICD). This ICD triggers the release of damage-related molecular patterns and CD8+ lymphocyte infiltration sensitizes the immune checkpoint blockade (αPD-L1) response, thereby eliciting a systemic anti-tumor immune response. Collectively, this comprehensive treatment regimen, driven by environmentally stimulated multiple pathways, overcomes the limitations of single therapeutic modalities, thereby improving tumor outcomes. Additionally, these findings provide valuable insights for strategies aimed at modulating the tumor immune microenvironment.

Navigating chimeric antigen receptor-engineered natural killer cells as drug carriers via three-dimensional mapping of the tumor microenvironment

Chimeric antigen receptor (CAR)-modified natural killer (NK) cells are recognized as promising immunotherapeutic agents for cancer treatment. However, the efficacy and trafficking of CAR-NK cells in solid tumors are hindered by the complex barriers present in the tumor microenvironment (TME). We have developed a novel strategy that utilizes living CAR-NK cells as carriers to deliver anticancer drugs specifically to the tumor site. We also introduce a time-lapse method for evaluating the efficacy and tumor specificity of CAR-NK cells using a two-photon microscope in live mouse models and three-dimensional (3D) tissue slide cultures. Our results demonstrate that CAR-NK cells exhibit enhanced antitumor immunity when combined with photosensitive chemicals in both in vitro and in vivo tumor models. Additionally, we have successfully visualized the trafficking, infiltration, and accumulation of drug-loaded CAR-NK cells in deeply situated TME using non-invasive intravital two-photon microscopy. Our findings highlight that tumor infiltration of CAR-NK cells can be intravitally monitored through the two-photon microscope approach. In conclusion, our study demonstrates the successful integration of CAR-NK cells as drug carriers and paves the way for combined cellular and small-molecule therapies in cancer treatment. Furthermore, our 3D platform offers a valuable tool for assessing the behavior of CAR cells within solid tumors, facilitating the development and optimization of immunotherapeutic strategies with clinical imaging approaches.

Deep-penetration functionalized cuttlefish ink nanoparticles for combating wound infections with synergetic photothermal-immunologic therapy

The challenge of wound infections post-surgery and open trauma caused by multidrug-resistant bacteria poses a constant threat to clinical treatment. As a promising antimicrobial treatment, photothermal therapy can effectively resolve the problem of drug resistance in conventional antibiotic antimicrobial therapy. Here, we report a deep-penetration functionalized cuttlefish ink nanoparticle (CINP) for photothermal and immunological therapy of wound infections. CINP is decorated with zwitterionic polymer (ZP, namely sulfobetaine methacrylate-methacrylate copolymer) to form CINP@ZP nanoparticles. Natural CINP is found to not only exhibit photothermal destruction of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), but also trigger macrophages-related innate immunity and enhance their antibacterial functions. The ZP coating on the surface of CINP enables nanoparticles to penetrate into deeply infected wound environment. In addition, CINP@ZP is further integrated into the thermosensitive Pluronic F127 gel (CINP@ZP-F127). After in situ spraying gel, CINP@ZP-F127 is also documented notable antibacterial effects in mice wound models infected with MRSA and E. coli. Collectively, this approach combining of photothermal therapy with immunotherapy can promote delivery efficiency of nanoparticles to the deep foci of infective wounds, and effectively eliminate wound infections.

Antibiotics Coupled with Photothermal Therapy for the Enhanced Killing of Bacteria

In this study, the application of ionic materials as a combination antibiotic drug was investigated. The fluoroquinolone, Norfloxacin, was converted into the ionic form and combined with the cationic dye, IR780+, using an ion-exchange reaction. The resulting ionic combination drug possesses two killing mechanisms in one compound. The antibiotic chemical mechanism along with the photothermal mechanism that was acquired by adding IR780 to the compound led to the development of a combination antibiotic drug. This ionic combination drug consisting of Norfloxacin anion and IR780 cation is easily dispersed in water using sonication waves. The parent compounds and ionic combination drug, dissolved in organic solvent and dispersed in water, were characterized, and the photophysical properties were studied in detail. It was discovered that the aqueous ionic combination drugs exhibited significant changes in absorbance and photoluminescent properties. In aqueous media, the dispersed ionic combination drug exhibited a very broad absorbance with an additional peak around 1000 nm which is advantageous in photothermal. A significant decrease in the quantum yield along with enhanced non-radiative rate constant was observed for the combination drug in the aqueous. The photothermal mechanism is present in both the parent IR780 dye and the ionic combination drug. The ionic combination drug displayed a high light-to-heat conversion efficiency and temperature increase similar to the parent dye. The combination of both killing mechanisms in the ionic combination drug resulted in enhanced antibacterial activity against Escherichia coli as compared to the parent Norfloxacin and IR780-I individually.