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1.
Chem Asian J ; : e202400679, 2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39073242

ABSTRACT

Despite the rapid development of thermally activated delayed fluorescent (TADF) materials, developing organic light-emitting diodes (OLEDs) with small efficiency roll-off remains a formidable challenge. Herein, we have designed a TADF molecule (mClSFO) based on the spiro fluorene skeleton. The highly twisted structure and multiple charge-transfer channels effectively suppress aggregation-caused quenching (ACQ) and endow mClSFO with excellent exciton dynamic properties to reduce efficiency roll-off. Fast radiative rate (kr) and rapid reverse intersystem crossing (RISC) rate (kRISC) of 1.6 × 107 s-1 and 1.07 × 106 s-1, respectively, are obtained in mClSFO. As a result, OLEDs based on mClSFO obtain impressive maximum external quantum efficiency (EQEmax) exceeding 20% across a wide doping concentration range of 10-60 wt%. 30 wt% doped OLED exhibits an EQEmax of 23.1% with a small efficiency roll-off, maintaining an EQE of 18.6% at 1000 cd m-2. The small efficiency roll-off and low concentration dependence observed in the TADF emitter underscore its significant potential.

2.
Acta Biomater ; 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39025392

ABSTRACT

The effectiveness of tumor treatment using reactive oxygen species as the primary therapeutic medium is hindered by limitations of tumor microenvironment (TME), such as intrinsic hypoxia in photodynamic therapy (PDT) and overproduction of reducing glutathione (GSH) in chemodynamic therapy (CDT). Herein, we fabricate metal-polyphenol self-assembled nanodots (Fe@BDP NDs) guided by second near-infrared (NIR-II) fluorescence imaging. The Fe@BDP NDs are designed for synergistic combination of type-I PDT and CDT-amplified ferroptosis. In a mildly acidic TME, Fe@BDP NDs demonstrate great Fenton activity, leading to the generation of highly toxic hydroxyl radicals from overproduced hydrogen peroxide in tumor cells. Furthermore, Fe@BDP NDs show favorable efficacy in type-I PDT, even in tolerating tumor hypoxia, generating active superoxide anion upon exposure to 808 nm laser irradiation. The significant efficiency in reactive oxygen species (ROS) products results in the oxidation of sensitive polyunsaturated fatty acids, accelerating lethal lipid peroxidation (LPO) bioprocess. Additionally, Fe@BDP NDs illustrate an outstanding capability for GSH depletion, causing the inactivation of glutathione peroxidase 4 and further promoting lethal LPO. The synergistic type-I photodynamic and chemodynamic cytotoxicity effectively trigger irreversible ferroptosis by disrupting the intracellular redox homeostasis. Moreover, Fe@BDP NDs demonstrate charming NIR-II fluorescence imaging capability and effectively accumulated at the tumor site, visualizing the distribution of Fe@BDP NDs and the treatment process. The chemo/photo-dynamic-amplified ferroptotic efficacy of Fe@BDP NDs was evidenced both in vitro and in vivo. This study presents a compelling approach to intensify ferroptosis via visualized CDT and PDT. STATEMENT OF SIGNIFICANCE: In this study, we detailed the fabrication of metal-polyphenol self-assembled nanodots (Fe@BDP NDs) guided by second near-infrared (NIR-II) fluorescence imaging, aiming to intensify ferroptosis via the synergistic combination of type-I PDT and CDT. In a mildly acidic TME, Fe@BDP NDs exhibited significant Fenton activity, resulting in the generation of highly toxic •OH from overproduced H2O2 in tumor cells. Fe@BDP NDs possessed a remarkable capability for GSH depletion, resulting in the inactivation of glutathione peroxidase 4 (GPX4) and further accelerating lethal LPO. This study presented a compelling approach to intensify ferroptosis via visualized CDT and PDT.

3.
Front Pharmacol ; 15: 1391399, 2024.
Article in English | MEDLINE | ID: mdl-38974035

ABSTRACT

Objective: JianPiHuaTan Formula (JPHTF), a traditional Chinese medicine (TCM), has been utilized as an adjunctive therapy for colorectal cancer (CRC). The study aims to evaluate the potential clinical benefits of JPHTF and its effectiveness in inhibiting tumor growth. Methods: 300 stage II/III CRC patients and 412 advanced CRC patients were enrolled to verify the clinical value of JPHTF in CRC treatment. Furthermore, CRC patient-derived xenograft (PDX) mice were utilized to investigate the regulatory mechanisms of JPHTF. Results: JPHTF significantly improved abdominal distension, shortness of breath, drowsiness, loss of appetite, sleep, and tiredness in stage II/III CRC patients, thereby improving their quality of life. Simultaneously, JPHTF served as a supportive therapy in extending the overall survival (OS) of stage IV CRC patients with RAS/RAF mutations undergoing chemotherapy. Additionally, JPHTF effectively impeded tumor progression in CRC PDX models with RAS mutation, accompanied by a reduction in tumor cell content in the JPHTF group. Transcriptomic analysis revealed the involvement of the Hippo and Hedgehog signaling pathways in JPHTF-mediated CRC inhibition. Furthermore, mice in the JPHTF group exhibited increased immune cell infiltration. Conclusion: These findings suggested that JPHTF may inhibits tumor growth in CRC with RAS mutation by modulating RAS/RAF downstream signaling pathways, specifically the Hippo and Hedgehog signaling, leading to increased immune cell infiltration.

4.
Mater Horiz ; 11(16): 3921-3927, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-38842068

ABSTRACT

Intramolecular exciplex systems featuring thermally activated delayed fluorescence (TADF) have garnered significant attention in the realm of organic light-emitting diodes (OLEDs). Nonetheless, the occurrence of organic sandwich intramolecular exciplexes remains rare due to structural limitations and synthetic challenges. Herein, we present a novel rigid acceptor-donor-acceptor (A-D-A) sandwich complex, dSFQP, characterized by two sp3 C-locking moieties. This compound exhibits TADF characteristics facilitated by a multiple through-space charge-transfer process. X-ray crystallographic analysis confirms the distinctive sandwich configuration. The parallel spatial arrangement and minimized A-D-A configuration enhance electronic interactions, resulting in a high photoluminescence quantum yield, rapid reverse intersystem crossing rate, and sluggish nonradiative decay rate. OLEDs employing dSFQP as the dopant achieve a maximum external quantum efficiency (EQE) of 28.5% with a low efficiency roll-off of merely 2.8% at 1000 cd m-2. Even at a high brightness of 10 000 cd m-2, the EQE remains notably high at 17.5%. Our current results provide an effective way to further innovate the design of new organic charge-transfer complexes.

5.
Sci Rep ; 14(1): 10005, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38693187

ABSTRACT

The Three Gorges Reservoir Area (TGRA) is characterized by unique geological features that increase its susceptibility to landslides. These slopes are especially prone to destabilization when influenced by external triggers like rainfall. This research focuses on the Piansongshu landslide within the TGRA, aiming at unraveling the complex internal deformation mechanisms of landslides triggered by rainfall and providing critical insights for their prevention and mitigation. The study begins with on-site geological surveys to meticulously examine the macroscopic signs and mechanisms of deformation. It then utilizes the GeoStudio numerical simulation software to assess the landslide's stability, focusing on the changes in internal seepage fields and stability under various rainfall scenarios. Results indicate that continuous rainfall leads to the formation of a temporary saturation zone on the slope, which gradually deepens. In regions with more pronounced deformation, the infiltration line at the leading edge of accumulation notably protrudes towards the surface. Notably, the stability coefficient of the secondary shear surface of the landslide fluctuates more significantly than that of the primary sliding surface. Higher rainfall intensity and longer duration are positively correlated with a more pronounced decrease in stability coefficients. The impact on stability also varies across different rainfall patterns. As rainfall infiltrates over time, the slope's safety factor gradually decreases. This reduction continues even post-rainfall, indicating a delayed restoration period before stability returns to a safe level. These results yield valuable data for forecasting and mitigating landslides.

6.
Nat Mater ; 23(7): 993-1001, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38594486

ABSTRACT

DNA origami is capable of spatially organizing molecules into sophisticated geometric patterns with nanometric precision. Here we describe a reconfigurable, two-dimensional DNA origami with geometrically patterned CD95 ligands that regulates immune cell signalling to alleviate rheumatoid arthritis. In response to pH changes, the device reversibly transforms from a closed to an open configuration, displaying a hexagonal pattern of CD95 ligands with ~10 nm intermolecular spacing, precisely mirroring the spatial arrangement of CD95 receptor clusters on the surface of immune cells. In a collagen-induced arthritis mouse model, DNA origami elicits robust and selective activation of CD95 death-inducing signalling in activated immune cells located in inflamed synovial tissues. Such localized immune tolerance ameliorates joint damage with no noticeable side effects. This device allows for the precise spatial control of cellular signalling, expanding our understanding of ligand-receptor interactions and is a promising platform for the development of pharmacological interventions targeting these interactions.


Subject(s)
Arthritis, Rheumatoid , DNA , Immune Tolerance , Signal Transduction , fas Receptor , Arthritis, Rheumatoid/immunology , Arthritis, Rheumatoid/metabolism , Arthritis, Rheumatoid/pathology , Animals , DNA/chemistry , DNA/immunology , Mice , fas Receptor/metabolism , fas Receptor/immunology , Fas Ligand Protein/metabolism , Fas Ligand Protein/immunology , Humans
7.
Adv Sci (Weinh) ; 11(23): e2402516, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38582500

ABSTRACT

Cuproptosis is a newly discovered form of programmed cell death significantly depending on the transport efficacy of copper (Cu) ionophores. However, existing Cu ionophores, primarily small molecules with a short blood half-life, face challenges in transporting enough amounts of Cu ions into tumor cells. This work describes the construction of carrier-free nanoparticles (Ce6@Cu NPs), which self-assembled by the coordination of Cu2+ with the sonosensitizer chlorin e6 (Ce6), facilitating sonodynamic-triggered combination of cuproptosis and ferroptosis. Ce6@Cu NPs internalized by U87MG cells induce a sonodynamic effect and glutathione (GSH) depletion capability, promoting lipid peroxidation and eventually inducing ferroptosis. Furthermore, Cu+ concentration in tumor cells significantly increases as Cu2+ reacts with reductive GSH, resulting in the downregulation of ferredoxin-1 and lipoyl synthase. This induces the oligomerization of lipoylated dihydrolipoamide S-acetyltransferase, causing proteotoxic stress and irreversible cuproptosis. Ce6@Cu NPs possess a satisfactory ability to penetrate the blood-brain barrier, resulting in significant accumulation in orthotopic U87MG-Luc glioblastoma. The sonodynamic-triggered combination of ferroptosis and cuproptosis in the tumor by Ce6@Cu NPs is evidenced both in vitro and in vivo with minimal side effects. This work represents a promising tumor therapeutic strategy combining ferroptosis and cuproptosis, potentially inspiring further research in developing logical and effective cancer therapies based on cuproptosis.


Subject(s)
Chlorophyllides , Copper , Ferroptosis , Glioblastoma , Porphyrins , Ferroptosis/drug effects , Glioblastoma/metabolism , Glioblastoma/therapy , Animals , Mice , Copper/chemistry , Humans , Porphyrins/chemistry , Porphyrins/pharmacology , Cell Line, Tumor , Nanoparticles/chemistry , Disease Models, Animal , Brain Neoplasms/therapy , Brain Neoplasms/metabolism
8.
Nanoscale ; 16(18): 8791-8806, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38606497

ABSTRACT

This review explores the potential of integrating nano-delivery systems with traditional Chinese herbal medicine, acupuncture, and Chinese medical theory. It highlights the intersections and potential of nano-delivery systems in enhancing the effectiveness of traditional herbal medicine and acupuncture treatments. In addition, it discusses how the integration of nano-delivery systems with Chinese medical theory can modernize herbal medicine and make it more readily accessible on a global scale. Finally, it analyzes the challenges and future directions in this field.


Subject(s)
Drug Delivery Systems , Medicine, Chinese Traditional , Nanotechnology , Humans , Acupuncture Therapy , Drugs, Chinese Herbal/chemistry
9.
Theranostics ; 14(6): 2464-2488, 2024.
Article in English | MEDLINE | ID: mdl-38646648

ABSTRACT

Cancer has remained a formidable challenge in medicine and has claimed an enormous number of lives worldwide. Theranostics, combining diagnostic methods with personalized therapeutic approaches, shows huge potential to advance the battle against cancer. This review aims to provide an overview of theranostics in oncology: exploring its history, current advances, challenges, and prospects. We present the fundamental evolution of theranostics from radiotherapeutics, cellular therapeutics, and nanotherapeutics, showcasing critical milestones in the last decade. From the early concept of targeted drug delivery to the emergence of personalized medicine, theranostics has benefited from advances in imaging technologies, molecular biology, and nanomedicine. Furthermore, we emphasize pertinent illustrations showcasing that revolutionary strategies in cancer management enhance diagnostic accuracy and provide targeted therapies customized for individual patients, thereby facilitating the implementation of personalized medicine. Finally, we describe future perspectives on current challenges, emerging topics, and advances in the field.


Subject(s)
Neoplasms , Precision Medicine , Theranostic Nanomedicine , Humans , Neoplasms/therapy , Neoplasms/diagnosis , Theranostic Nanomedicine/methods , Precision Medicine/methods , Drug Delivery Systems/methods , Nanomedicine/methods , History, 20th Century , Animals , History, 21st Century
10.
Angew Chem Int Ed Engl ; 63(16): e202319982, 2024 04 15.
Article in English | MEDLINE | ID: mdl-38361437

ABSTRACT

Enzymes are considered safe and effective therapeutic tools for various diseases. With the increasing integration of biomedicine and nanotechnology, artificial nanozymes offer advanced controllability and functionality in medical design. However, several notable gaps, such as catalytic diversity, specificity and biosafety, still exist between nanozymes and their native counterparts. Here we report a non-metal single-selenium (Se)-atom nanozyme (SeSAE), which exhibits potent nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-mimetic activity. This novel single atom nanozyme provides a safe alternative to conventional metal-based catalysts and effectively cuts off the cellular energy and reduction equivalents through its distinctive catalytic function in tumors. In this study, we have demonstrated the substantial efficacy of SeSAE as an antitumor nanomedicine across diverse mouse models without discernible systemic adverse effects. The mechanism of the NADPH oxidase-like activity of the non-metal SeSAE was rationalized by density functional theory calculations. Furthermore, comprehensive elucidation of the biological functions, cell death pathways, and metabolic remodeling effects of the nanozyme was conducted, aiming to provide valuable insights into the development of single atom nanozymes with clinical translation potential.


Subject(s)
Nanotechnology , Neoplasms , Animals , Mice , Metals , Catalysis , Neoplasms/drug therapy , Nanomedicine
11.
Chem Soc Rev ; 53(7): 3224-3252, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38379286

ABSTRACT

Neoantigens play a pivotal role in the field of tumour therapy, encompassing the stimulation of anti-tumour immune response and the enhancement of tumour targeting capability. Nonetheless, numerous factors directly influence the effectiveness of neoantigens in bolstering anti-tumour immune responses, including neoantigen quantity and specificity, uptake rates by antigen-presenting cells (APCs), residence duration within the tumour microenvironment (TME), and their ability to facilitate the maturation of APCs for immune response activation. Nanotechnology assumes a significant role in several aspects, including facilitating neoantigen release, promoting neoantigen delivery to antigen-presenting cells, augmenting neoantigen uptake by dendritic cells, shielding neoantigens from protease degradation, and optimizing interactions between neoantigens and the immune system. Consequently, the development of nanotechnology synergistically enhances the efficacy of neoantigens in cancer theranostics. In this review, we provide an overview of neoantigen sources, the mechanisms of neoantigen-induced immune responses, and the evolution of precision neoantigen-based nanomedicine. This encompasses various therapeutic modalities, such as neoantigen-based immunotherapy, phototherapy, radiotherapy, chemotherapy, chemodynamic therapy, and other strategies tailored to augment precision in cancer therapeutics. We also discuss the current challenges and prospects in the application of neoantigen-based precision nanomedicine, aiming to expedite its clinical translation.


Subject(s)
Cancer Vaccines , Neoplasms , Humans , Antigens, Neoplasm , Precision Medicine , Neoplasms/diagnosis , Neoplasms/therapy , Immunotherapy , Nanotechnology , Tumor Microenvironment
12.
Bioact Mater ; 34: 414-421, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38292411

ABSTRACT

Tumor hypoxia diminishes the effectiveness of traditional type II photodynamic therapy (PDT) due to oxygen consumption. Type I PDT, which can operate independently of oxygen, is a viable option for treating hypoxic tumors. In this study, we have designed and synthesized JSK@PEG-IR820 NPs that are responsive to the tumor microenvironment (TME) to enhance type I PDT through glutathione (GSH) depletion. Our approach aims to expand the sources of therapeutic benefits by promoting the generation of superoxide radicals (O2-.) while minimizing their consumption. The diisopropyl group within PEG-IR820 serves a dual purpose: it functions as a pH sensor for the disassembly of the NPs to release JSK and enhances intermolecular electron transfer to IR820, facilitating efficient O2-. generation. Simultaneously, the release of JSK leads to GSH depletion, resulting in the generation of nitric oxide (NO). This, in turn, contributes to the formation of highly cytotoxic peroxynitrite (ONOO-.), thereby enhancing the therapeutic efficacy of these NPs. NIR-II fluorescence imaging guided therapy has achieved successful tumor eradication with the assistance of laser therapy.

13.
Adv Mater ; 36(1): e2304848, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37526997

ABSTRACT

Molecular fluorophores emitting in the second near-infrared (NIR-II, 1000-1700 nm) window with strong optical harvesting and high quantum yields hold great potential for in vivo deep-tissue bioimaging and high-resolution biosensing. Recently, J-aggregates are harnessed to engineer long-wavelength NIR-II emitters and show unique superiority in tumor detection, vessel mapping, surgical navigation, and phototheranostics due to their bathochromic-shifted optical bands in the required slip-stacked arrangement aggregation state. However, despite the preliminary progress of NIR-II J-aggregates and theoretical study of structure-property relationships, further paradigms of NIR-II J-aggregates remain scarce due to the lack of study on aggregated fluorophores with slip-stacked fashion. In this effort, how to utilize the specific molecular structure to form slip-stacked packing motifs with J-type aggregated exciton coupling is emphatically elucidated. First, several molecular regulating strategies to achieve NIR-II J-aggregates containing intermolecular interactions and external conditions are positively summarized and deeply analyzed. Then, the recent reports on J-aggregates for NIR-II bioimaging and theranostics are systematically summarized to provide a clear reference and direction for promoting the development of NIR-II organic fluorophores. Eventually, the prospective efforts on ameliorating and promoting NIR-II J-aggregates to further clinical practices are outlined.


Subject(s)
Fluorescent Dyes , Optical Imaging , Prospective Studies , Optical Imaging/methods , Fluorescent Dyes/chemistry
14.
Sci Rep ; 13(1): 12926, 2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37558819

ABSTRACT

Landslides are the most widely distributed geological hazards in the Three Gorges Reservoir Area (TGRA). Understanding the deformation mechanism and evolution of landslides is of great significance for their prevention and control. In this study, we focused on the Zhangjiacitang landslide, a typical bank landslide in the TGRA. We analyzed the relationship between landslide deformation and water level fluctuations and rainfall, based on accumulated displacement monitoring data, to clarify their triggering factors and deformation mechanism. The results show that the Zhangjiacitang landslide is a large-scale accumulation landslide. Under the influence of cyclic water level fluctuations and periodic rainfall, the accumulated displacement-time curve shows a "stepped" characteristic. Heavy rainfall emerged as the primary factor influencing the deformation of the Zhangjiacitang landslide, leading to substantial deformation throughout different periods. The deformation of the landslide exhibited a positive correlation with the intensity of rainfall. In contrast, the impact of water level changes on the landslide deformation was more intricate. A rapid water level drop (> 0.3 m/d) tended to intensify the landslide deformation, while the slow water level drop period (< 0.3 m/d) did not exhibit such an effect. This study emphasizes the need for closely monitoring the landslide status during heavy rainfall periods and rapid water level decline periods. The findings of this study provide a certain reference for landslide monitoring, early warning, prevention and control in the TGRA.

16.
Front Pharmacol ; 14: 1091177, 2023.
Article in English | MEDLINE | ID: mdl-37324453

ABSTRACT

Objective: Nowadays, primary liver carcinoma (PLC) is one of the major contributors to the global cancer burden, and China has the highest morbidity and mortality rates in the world. As a well-known Chinese herbal medicine (CHM) prescription, Huatan Sanjie Granules (HSG) has been used clinically for many years to treat PLC with remarkable efficacy, but the underlying mechanism of action remains unclear. Methods: A clinical cohort study was conducted to observe the overall survival of PLC patients with vs. without oral administration of HSG. Meanwhile, the BATMAN-TCM database was used to retrieve the potential active ingredients in the six herbs of HSG and their corresponding drug targets. PLC-related targets were then screened through the Gene Expression Omnibus (GEO) database. The protein-protein interaction (PPI) network of targets of HSG against PLC was constructed using Cytoscape software. The cell function assays were further carried out for verification. Results: The results of the cohort study showed that the median survival time of PLC patients exposed to HSG was 269 days, which was 23 days longer than that of the control group (HR, 0.62; 95% CI, 0.38-0.99; p = 0.047). In particular, the median survival time of Barcelona Clinic Liver Cancer stage C patients was 411 days in the exposure group, which was 137 days longer than that in the control group (HR, 0.59; 95% CI, 0.35-0.96; p = 0.036). Meanwhile, the enrichment analysis result for the obtained PPI network consisting of 362 potential core therapeutic targets suggest that HSG may inhibit the growth of liver cancer (LC) cells by blocking the PI3K-Akt/MAPK signaling pathways. Furthermore, the above prediction results were verified by a series of in vitro assays. Specifically, we found that the expressions TP53 and YWHA2, the targets of the hepatitis B virus signaling pathway, were significantly affected by HSG. Conclusion: HSG shows promising therapeutic efficacy in the adjuvant treatment of PLC.

17.
Angew Chem Int Ed Engl ; 62(27): e202304312, 2023 07 03.
Article in English | MEDLINE | ID: mdl-37137872

ABSTRACT

The metabolic reprogramming of tumors requires high levels of adenosine triphosphate (ATP) to maintain therapeutic resistance, posing a major challenge for photothermal therapy (PTT). Although raising the temperature helps in tumor ablation, it frequently leads to severe side effects. Therefore, improving the therapeutic response and promoting healing are critical considerations in the development of PTT. Here, we proposed a gas-mediated energy remodeling strategy to improve mild PTT efficacy while minimizing side effects. In the proof-of-concept study, a Food and Drug Administration (FDA)-approved drug-based hydrogen sulfide (H2 S) donor was developed to provide a sustained supply of H2 S to tumor sites, serving as an adjuvant to PTT. This approach proved to be highly effective in disrupting the mitochondrial respiratory chain, inhibiting ATP generation, and reducing the overexpression of heat shock protein 90 (HSP90), which ultimately amplified the therapeutic outcome. With the ability to reverse tumor thermotolerance, this strategy delivered a greatly potent antitumor response, achieving complete tumor ablation in a single treatment while minimizing harm to healthy tissues. Thus, it holds great promise to be a universal solution for overcoming the limitations of PTT and may serve as a valuable paradigm for the future clinical translation of photothermal nanoagents.


Subject(s)
Nanoparticles , Neoplasms , Humans , Photothermal Therapy , Neoplasms/drug therapy , Temperature , Cell Line, Tumor , Nanoparticles/therapeutic use , Phototherapy
18.
Mater Horiz ; 10(8): 3014-3023, 2023 Jul 31.
Article in English | MEDLINE | ID: mdl-37194333

ABSTRACT

Phototherapy-induced hypoxia in the tumor microenvironment (TME) is responsible for diminished therapeutic efficacy. Designing an intelligent nanosystem capable of responding to hypoxia for TME-responsive drug delivery will, to some extent, improve the therapeutic efficacy and reduce side effects. Semiconducting polymers with high photothermal conversion efficiency and photostability have tremendous potential as phototheranostics. In this paper, hypoxia-activatable tirapazamine (TPZ) was conjugated onto poly(ethylene glycol) to form a pH-sensitive poly-prodrug, PEG-TPZ, that can be triggered by the low acidity of the TME to cleave the acylamide bond for controllable drug release. PEG-TPZ was then used to encapsulate a semiconducting polymer (TDPP) for NIR-II-fluorescence-imaging-guided synergistic therapy. The reactive oxygen species (ROS) generation and ultrahigh photothermal conversion efficiency (∼58.6%) of the TDPP@PEG-TPZ NPs leads to the destruction of the tumor blood vessels, thus further activating the hypoxia-induced chemotherapy of TPZ. As a result, effective tumor regression was achieved after laser irradiation.

19.
Small ; 19(30): e2300750, 2023 07.
Article in English | MEDLINE | ID: mdl-37058076

ABSTRACT

Nanomaterials with enzyme-mimicking properties, coined as nanozymes, are a promising alternative to natural enzymes owing to their remarkable advantages, such as high stability, easy preparation, and favorable catalytic performance. Recently, with the rapid development of nanotechnology and characterization techniques, single atom nanozymes (SAzymes) with atomically dispersed active sites, well-defined electronic and geometric structures, tunable coordination environment, and maximum metal atom utilization are developed and exploited. With superior catalytic performance and selectivity, SAzymes have made impressive progress in biomedical applications and are expected to bridge the gap between artificial nanozymes and natural enzymes. Herein, the recent advances in SAzyme preparation methods, catalytic mechanisms, and biomedical applications are systematically summarized. Their biomedical applications in cancer therapy, oxidative stress cytoprotection, antibacterial therapy, and biosensing are discussed in depth. Furthermore, to appreciate these advances, the main challenges, and prospects for the future development of SAzymes are also outlined and highlighted in this review.


Subject(s)
Nanostructures , Nanostructures/chemistry , Catalysis , Nanotechnology
20.
ACS Nano ; 17(3): 3064-3076, 2023 02 14.
Article in English | MEDLINE | ID: mdl-36646112

ABSTRACT

As a rising generation of nanozymes, single atom enzymes show significant promise for cancer therapy, due to their maximum atom utilization efficiency and well-defined electronic structures. However, it remains a tremendous challenge to precisely produce a heteroatom-doped single atom enzyme with an expected coordination environment. Herein, we develop an anion exchange strategy for precisely controlled production of an edge-rich sulfur (S)- and nitrogen (N)-decorated nickel single atom enzyme (S-N/Ni PSAE). In particular, sulfurized S-N/Ni PSAE exhibits stronger peroxidase-like and glutathione oxidase-like activities than the nitrogen-monodoped nickel single atom enzyme, which is attributed to the vacancies and defective sites of sulfurized nitrogen atoms. Moreover, both in vitro and in vivo results demonstrate that, compared with nitrogen-monodoped N/Ni PSAE, sulfurized S-N/Ni PSAE more effectively triggers ferroptosis of tumor cells via inactivating glutathione peroxidase 4 and inducing lipid peroxidation. This study highlights the enhanced catalytic efficacy of a polynary heteroatom-doped single atom enzyme for ferroptosis-based cancer therapy.


Subject(s)
Ferroptosis , Neoplasms , Humans , Nickel , Peroxidase , Nitrogen , Neoplasms/drug therapy
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