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2.
Bioact Mater ; 42: 628-643, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39386355

RESUMO

Keeping steps ahead of the bacteria in the race for more efficacious antibacterial strategies is increasingly difficult with the advent of bacterial resistance genes. Herein, we engineered copper sulfide nanoclusters (CuSx NCs) with variable sulfur defects for enhanced dual-treatment of bacterial infections by manipulating photothermal effects and Fenton-like activity. Next, by encasing CuSx NCs with a complex mixture of amino acids and short peptides derived from Luria-Bertani bacterial culture media as a protein corona, we managed to coax E. Coli to take up these CuSx NCs. As a whole, Amino-Pep-CuSx NCs was perceived as a food source and actively consumed by bacteria, enhancing their effective uptake by at least 1.5-fold greater than full length BSA protein BSA-corona CuSx NCs. Through strategically using defect-engineering, we successfully fine-tune photothermal effect and Fenton-like capacity of CuSx NCs. Increased sulfur defects lead to reduced but sufficient heat generation under solar-light irradiation and increased production of toxic hydroxyl radicals. By fine-tuning sulfur defects during synthesis, we achieve CuSx NCs with an optimal synergistic effect, significantly enhancing their bactericidal properties. These ultra-small and biodegradable CuSx NCs can rapidly break down after treatment for clearance. Thus, Amino-Pep-CuSx NCs demonstrate effective eradication of bacteria both in vitro and in vivo because of their relatively high uptake, optimal balanced photothermal and chemodynamic outcomes. Our study offers a straightforward and efficient method to enhance bacterial uptake of next generation of antibacterial agents.

3.
Nat Nanotechnol ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39327512

RESUMO

The success of personalized cancer immunotherapy depends on the initial tumour antigenic presentation to dendritic cells and macrophages. Tumour-derived extracellular vesicles (TEVs) contain abundant tumour antigenic molecules. The presence of anti-phagocytotic signals such as cluster of differentiation 47 (CD47) on the surface of the TEVs, however, leads to evasion of the same dendritic cells and macrophages. Here we show that iron oxide hydroxide nanocomposites can successfully mask TEV surfaces and unblock phagocytosis without affecting extracellular vesicles' elicited immune goals. After internalization, the mask disintegrates in the lysosome, releasing the tumour antigenic cargo. This triggers antigen presentation and promotes dendritic cell activation and maturation and macrophage reprogramming in animal models, leading to a drastic reduction of tumour volume and metastasis, and in human malignant pleural effusion clinical samples. This straightforward masking strategy eliminates the ubiquitous anti-phagocytosis block found in clinical samples and can be applied universally across all patient-specific TEVs as tumour antigenic agents for enhanced immunotherapy.

4.
Nanoscale Horiz ; 9(7): 1190-1199, 2024 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-38757185

RESUMO

Antibacterial nanoagents have been increasingly developed due to their favorable biocompatibility, cost-effective raw materials, and alternative chemical or optical properties. Nevertheless, there is still a pressing need for antibacterial nanoagents that exhibit outstanding bacteria-binding capabilities and high antibacterial efficiency. In this study, we constructed a multifunctional cascade bioreactor (GCDCO) as a novel antibacterial agent. This involved incorporating carbon dots (CDs), cobalt sulfide quantum dots (CoSx QDs), and glucose oxidase (GOx) to enhance bacterial inhibition under sunlight irradiation. The GCDCO demonstrated highly efficient antibacterial capabilities attributed to its favorable photothermal properties, photodynamic activity, as well as the synergistic effects of hyperthermia, glucose-augmented chemodynamic action, and additional photodynamic activity. Within this cascade bioreactor, CDs played the role of a photosensitizer for photodynamic therapy (PDT), capable of generating ˙O2- even under solar light irradiation. The CoSx QDs not only functioned as a catalytic component to decompose hydrogen peroxide (H2O2) and generate hydroxyl radicals (˙OH), but they also served as heat generators to enhance the Fenton-like catalysis process. Furthermore, GOx was incorporated into this cascade bioreactor to internally supply H2O2 by consuming glucose for a Fenton-like reaction. As a result, GCDCO could generate a substantial amount of reactive oxygen species (ROS), leading to a significant synergistic effect that greatly induced bacterial death. Furthermore, the in vitro antibacterial experiment revealed that GCDCO displayed notably enhanced antibacterial activity against E. coli (99+ %) when combined with glucose under simulated sunlight, surpassing the efficacy of the individual components. This underscores its remarkable efficiency in combating bacterial growth. Taken together, our GCDCO demonstrates significant potential for use in the routine treatment of skin infections among diabetic patients.


Assuntos
Antibacterianos , Glucose Oxidase , Fotoquimioterapia , Pontos Quânticos , Pontos Quânticos/química , Pontos Quânticos/efeitos da radiação , Glucose Oxidase/química , Fotoquimioterapia/métodos , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Cobalto/química , Cobalto/farmacologia , Luz , Carbono/química , Carbono/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Reatores Biológicos , Espécies Reativas de Oxigênio/metabolismo
5.
ACS Nano ; 18(13): 9613-9626, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38502546

RESUMO

Recent discoveries in commensal microbiota demonstrate the great promise of intratumoral bacteria as attractive molecular targets of tumors in improving cancer treatment. However, direct leveraging of in vivo antibacterial strategies such as antibiotics to potentiate cancer therapy often leads to uncertain effectiveness, mainly due to poor selectivity and potential adverse effects. Here, building from the clinical discovery that patients with breast cancer featured rich commensal bacteria, we developed an activatable biointerface by encapsulating commensal bacteria-derived extracellular vesicles (BEV) with a responsive nanocloak to potentiate immunoreactivity against intratumoral bacteria and breast cancer. We show that the interfacially cloaked BEV (cBEV) not only overcame serious systemic side responses but also demonstrated heightened immunogenicity by intercellular responsive immunogenicity, facilitating dendritic cell maturation through activating the cGAS-STING pathway. As a preventive measure, vaccination with nanocloaked cBEVs achieved strong protection against bacterial infection, largely providing prophylactic efficiency against tumor challenges. When treated in conjunction with immune checkpoint inhibitor anti-PD-L1 antibodies, the combined approach elicited a potent tumor-specific immune response, synergistically inhibiting tumor progression and mitigating lung metastases.


Assuntos
Neoplasias da Mama , Neoplasias , Humanos , Feminino , Imunoterapia , Neoplasias/terapia , Neoplasias da Mama/metabolismo , Imunidade , Bactérias , Microambiente Tumoral
6.
Environ Res ; 242: 117781, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38036212

RESUMO

In this study, a novel magnetic nanocomposite of Ru@Fe3O4/rGO was successfully synthesized by a simple hydro-thermal method. The Ru@Fe3O4/rGO particles were assembled and immobilized for innovative magnetically assembled electrode (MAE) without any binder, and the electrode was further applied in heterogeneous electro-Fenton (hetero-EF) process for the degradation of diclofenac (DCF). The results showed that rGO could remarkably enhance the conductivity and catalyze the two-electron oxygen reduction, which greatly improved the generation of H2O2. In addition, the mixture valence of Fe and Ru species might provide rich reaction sites and enhance electron transfer by synergy. Thus, the Ru@Fe3O4/rGO MAE exhibited a stable and high electrocatalytic activity in the hetero-EF process for DCF degradation over a wide pH range from 2 to 9 owing to the higher electroactive surface area (EASA) and lower charge/mass-transfer resistance. The DCF degradation efficiency could reach about 100% within 90 min under pH 5 and current 40 mA, and the Ru@Fe3O4/rGO MAE showed high stability and reusability after five cycles. Theoretically, 1O2 and •OH were the main reactive oxygen species (ROS) participating in DCF degradation in the Ru@Fe3O4/rGO MAE hetero-EF process. Furthermore, according to the LC-MS/MS intermediates, the possible DCF degradation pathway was deduced including dechlorination, hydroxylation and ring opening attacked by ROS. Eleven intermediates were detected during DCF degradation in the MAE hetero-EF process, and the ecological risk of DCF degradation in Ru@Fe3O4/rGO MAE hetero-EF process was significantly reduced. This study provides new insights into the magnetically assembled electrode of Ru@Fe3O4/rGO and displays a new practical application prospect of the materials for high-efficient removal and degradation of DCF from wastewater.


Assuntos
Diclofenaco , Poluentes Químicos da Água , Peróxido de Hidrogênio , Espécies Reativas de Oxigênio , Cromatografia Líquida , Espectrometria de Massas em Tandem , Eletrodos , Oxirredução
7.
Small Methods ; 8(3): e2301368, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38009516

RESUMO

The presence of toxic organic pollutants in aquatic environments poses significant threats to human health and global ecosystems. Photocatalysis that enables in situ production and activation of H2 O2 presents a promising approach for pollutant removal; however, the processes of H2 O2 production and activation potentially compete for active sites and charge carriers on the photocatalyst surface, leading to limited catalytic performance. Herein, a hierarchical 2D/2D heterojunction nanosphere composed of ultrathin BiOBr and BiOI nanosheets (BiOBr/BiOI) is developed by a one-pot microwave-assisted synthesis to achieve in situ H2 O2 production and activation for efficient photocatalytic wastewater treatment. Various experimental and characterization results reveal that the BiOBr/BiOI heterojunction facilitates efficient electron transfer from BiOBr to BiOI, enabling the one-step two-electron O2 reduction for H2 O2 production. Moreover, the ultrathin BiOI provides abundant active sites for H2 O2 adsorption, promoting in situ H2 O2 activation for •O2 - generation. As a result, the BiOBr/BiOI hybrid exhibits excellent activity for pollutant degradation with an apparent rate constant of 0.141 min-1 , which is 3.8 and 47.3 times that of pristine BiOBr and BiOI, respectively. This work expands the range of the materials suitable for in situ H2 O2 production and activation, paving the way toward sustainable environmental remediation using solar energy.

8.
Adv Sci (Weinh) ; 10(28): e2303448, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37544890

RESUMO

Piezo-assisted photocatalysis (namely, piezo-photocatalysis), which utilizes mechanical energy to modulate spatial and energy distribution of photogenerated charge carriers, presents a promising strategy for molecule activation and reactive oxygen species (ROS) generation toward applications such as environmental remediation. However, similarly to photocatalysis, piezo-photocatalysis also suffers from inferior charge separation and utilization efficiency. Herein, a Z-scheme heterojunction composed of single Ag atoms-anchored polymeric carbon nitride (Ag-PCN) and SnO2- x is developed for efficient charge carrier transfer/separation both within the catalyst and between the catalyst and surface oxygen molecules (O2 ). As revealed by charge dynamics analysis and theoretical simulations, the synergy between the single Ag atoms and the Z-scheme heterojunction initiates a cascade electron transfer from SnO2- x to Ag-PCN and then to O2 adsorbed on Ag. With ultrasound irradiation, the polarization field generated within the piezoelectric hybrid further accelerates charge transfer and regulates the O2 activation pathway. As a result, the Ag-PCN/SnO2- x catalyst efficiently activates O2 into ·O2 - , ·OH, and H2 O2 under co-excitation of visible light and ultrasound, which are consequently utilized to trigger aerobic degradation of refractory antibiotic pollutants. This work provides a promising strategy to maneuver charge transfer dynamics for efficient piezo-photocatalysis by integrating single-atom catalysts (SACs) with Z-scheme heterojunction.

9.
ACS Appl Mater Interfaces ; 15(21): 25427-25436, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37204052

RESUMO

The treatment of cutaneous wounds involving complex biological processes has become a significant public health concern worldwide. Here, we developed an efficient extracellular vesicle (EV) ink to regulate the inflammatory microenvironment and promote vascular regeneration for wound healing. The technology, termed portable bioactive ink for tissue healing (PAINT), leverages bioactive M2 macrophage-derived EVs (EVM2) and a sodium alginate precursor, forming a biocompatible EV-Gel within 3 min after mixing, enabling it to be smeared on wounds in situ to meet diverse morphologies. The bioactive EVM2 reprogram macrophage polarization and promote the proliferation and migration of endothelial cells, thereby effectively regulating inflammation and enhancing angiogenesis in wounds. Through integration with a 3D printing pen, the platform enables EV-Gel to be applied to wound sites having arbitrary shapes and sizes with geometric matches for tissue repairment. When evaluated using a mouse wound model, PAINT technology accelerates cutaneous wound healing by promoting the angiogenesis of endothelial cells and the polarization of macrophages to M2 phenotype in vivo, demonstrating the high potential of bioactive EV ink as a portable biomedical platform for healthcare.


Assuntos
Células Endoteliais , Vesículas Extracelulares , Tinta , Cicatrização , Macrófagos
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 297: 122735, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37080055

RESUMO

2,4,6-trinitrophenyl phenol (TNP) and dichromate (Cr2O72-) have serious toxicological effects on environment. Therefore, it is very important to detect and remove TNP and Cr2O72- in environmental matrix. In this work, a dual-functional UiO type metal-organic framework (Zr-Sti) was synthesized for simultaneous detection and removal of those pollutants in aqueous solution. As for detection, Zr-Sti exhibited sensitive and selective fluorescence response to TNP and Cr2O72- with detection limit below µM level, and possible mechanism behind was proposed and partially supported by experiment data. In addition, adsorption capacity of the prepared Zr-Sti for TNP and Cr2O72- was further investigated to evaluate its performance in pollutant removal from aqueous solution, and the mechanism behinds the obtained high removal efficiency was proposed. These results together with the satisfied recovery for simultaneous detection of TNP and Cr2O72- in real sample, indicate the potential of the prepared Zr-Sti material in the field of environment monitoring and remediation.

11.
ACS Nano ; 17(9): 7953-7978, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37071059

RESUMO

Hydrogels, as one of the most feasible soft biomaterials, have gained considerable attention in therapeutic applications by virtue of their tunable properties including superior patient compliance, good biocompatibility and biodegradation, and high cargo-loading efficiency. However, hydrogel application is still limited by some challenges like inefficient encapsulation, easy leakage of loaded cargoes, and the lack of controllability. Recently, nanoarchitecture-integrated hydrogel systems were found to be therapeutics with optimized properties, extending their bioapplication. In this review, we briefly presented the category of hydrogels according to their synthetic materials and further discussed the advantages in bioapplication. Additionally, various applications of nanoarchitecture hybrid hydrogels in biomedical engineering are systematically summarized, including cancer therapy, wound healing, cardiac repair, bone regeneration, diabetes therapy, and obesity therapy. Last, the current challenges, limitations, and future perspectives in the future development of nanoarchitecture-integrated flexible hydrogels are addressed.


Assuntos
Hidrogéis , Engenharia Tecidual , Humanos , Hidrogéis/uso terapêutico , Materiais Biocompatíveis/farmacologia , Cicatrização , Regeneração Óssea
12.
ACS Nano ; 17(5): 4193-4229, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36802513

RESUMO

Plasmonic nanostructures have shown immense potential in photocatalysis because of their distinct photochemical properties associated with tunable photoresponses and strong light-matter interactions. The introduction of highly active sites is essential to fully exploit the potential of plasmonic nanostructures in photocatalysis, considering the inferior intrinsic activities of typical plasmonic metals. This review focuses on active site-engineered plasmonic nanostructures with enhanced photocatalytic performance, wherein the active sites are classified into four types (i.e., metallic sites, defect sites, ligand-grafted sites, and interface sites). The synergy between active sites and plasmonic nanostructures in photocatalysis is discussed in detail after briefly introducing the material synthesis and characterization methods. Active sites can promote the coupling of solar energy harvested by plasmonic metal to catalytic reactions in the form of local electromagnetic fields, hot carriers, and photothermal heating. Moreover, efficient energy coupling potentially regulates the reaction pathway by facilitating the excited state formation of reactants, changing the status of active sites, and creating additional active sites using photoexcited plasmonic metals. Afterward, the application of active site-engineered plasmonic nanostructures in emerging photocatalytic reactions is summarized. Finally, a summary and perspective of the existing challenges and future opportunities are presented. This review aims to deliver some insights into plasmonic photocatalysis from the perspective of active sites, expediting the discovery of high-performance plasmonic photocatalysts.

13.
Nanoscale ; 15(4): 1609-1618, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36602001

RESUMO

Formaldehyde (HCHO) is widely viewed as a carcinogenic volatile organic compound in indoor air pollution that can seriously threaten human health and life. Thus, there is a critical need to develop gas sensors with improved sensing performance, including outstanding selectivity, low operating temperature, high responsiveness, and short recovery time, for HCHO detection. Currently, doping is considered an effective strategy to raise the sensing performance of gas sensors. Herein, various rare earth elements-doped indium oxide (RE-In2O3) nanospheres were fabricated as gas sensors for improved HCHO detection via a facile and environmentally solvothermal method. Such RE-In2O3 nanosphere-based sensors exhibited remarkable gas-sensing performance, including a high selectivity and stability in air. Compared with pure, Yb-, Dy-doped In2O3 and different La ratios doped into In2O3, 6% La-doped In2O3 (La-In2O3) nanosphere-based sensors demonstrated a high response value of 210 to 100 ppm at 170 °C, which was around 16 times higher than that of the pure In2O3 sensor, and also exhibited a detection limit of 10.9 ppb, and a response time of 30 s to 100 ppm HCHO with a recovery time of 160 s. Finally, such superior sensing performance of the 6% La-In2O3 sensors was proposed to be attributed to the synergistic effect of the large specific surface area and enhanced surface oxygen vacancies on the surface of In2O3 nanospheres, which produced chemisorbed oxygen species to release electrons and provided abundant reaction sites for HCHO gas. This study sheds new light on designing nanomaterials to build gas sensors for HCHO detection.

14.
Adv Drug Deliv Rev ; 192: 114644, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36493906

RESUMO

Phototheranostic based on photothermal therapy (PTT) and photoacoustic imaging (PAI), as one of avant-garde medical techniques, have sparked growing attention because it allows noninvasive, deeply penetrative, and highly selective and effective therapy. Among a variety of phototheranostic nanoagents, single-component inorganic nanostructures are found to be novel and attractive PAI and PTT combined nanotheranostic agents and received tremendous attention, which not only exhibit structural controllability, high tunability in physiochemical properties, size-dependent optical properties, high reproducibility, simple composition, easy functionalization, and simple synthesis process, but also can be endowed with multiple therapeutic and imaging functions, realizing the superior therapy result along with bringing less foreign materials into body, reducing systemic side effects and improving the bioavailability. In this review, according to their synthetic components, conventional single-component inorganic nanostructures are divided into metallic nanostructures, metal dichalcogenides, metal oxides, carbon based nanostructures, upconversion nanoparticles (UCNPs), metal organic frameworks (MOFs), MXenes, graphdiyne and other nanostructures. On the basis of this category, their detailed applications in PAI guide PTT of tumor treatment are systematically reviewed, including synthesis strategies, corresponding performances, and cancer diagnosis and therapeutic efficacy. Before these, the factors to influence on photothermal effect and the principle of in vivo PAI are briefly presented. Finally, we also comprehensively and thoroughly discussed the limitation, potential barriers, future perspectives for research and clinical translation of this single-component inorganic nanoagent in biomedical therapeutics.


Assuntos
Nanopartículas , Nanoestruturas , Neoplasias , Técnicas Fotoacústicas , Humanos , Terapia Fototérmica , Fototerapia/métodos , Técnicas Fotoacústicas/métodos , Reprodutibilidade dos Testes , Nanoestruturas/uso terapêutico , Nanoestruturas/química , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/terapia
15.
Adv Sci (Weinh) ; 10(3): e2204814, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36373730

RESUMO

Extracellular vesicles (EVs) have increasingly been recognized as important cell surrogates influencing many pathophysiological processes, including cellular homeostasis, cancer progression, neurologic disease, and infectious disease. These behaviors enable EVs broad application prospects for clinical application in disease diagnosis and treatment. Many studies suggest that EVs are superior to conventional synthetic carriers in terms of drug delivery and circulating biomarkers for early disease diagnosis, opening up new frontiers for modern theranostics. Despite these clinical potential, EVs containing diverse cellular components, such as nucleic acids, proteins, and metabolites are highly heterogeneous and small size. The limitation of preparatory, engineering and analytical technologies for EVs poses technical barriers to clinical translation. This article aims at present a critical overview of emerging technologies in EVs field for biomedical applications and challenges involved in their clinic translations. The current methods for isolation and identification of EVs are discussed. Additionally, engineering strategies developed to enhance scalable production and improved cargo loading as well as tumor targeting are presented. The superior clinical potential of EVs, particularly in terms of different cell origins and their application in the next generation of diagnostic and treatment platforms, are clarified.


Assuntos
Vesículas Extracelulares , Neoplasias , Humanos , Medicina de Precisão , Vesículas Extracelulares/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/diagnóstico , Neoplasias/terapia , Neoplasias/metabolismo , Nanotecnologia
16.
Dalton Trans ; 52(1): 109-117, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36464993

RESUMO

Since the abuse of antibiotic oxytetracycline (OTC) poses a serious threat to the environment and human health, it is of great importance to develop sensitive fluorescent probes for its rapid and in situ detection. Herein, a dual fluorescence response probe based on an aluminum-incorporated metal-organic framework (MOF) was presented for OTC assay. Unlike internal references that demonstrate an independent and stable fluorescence signal intensity in traditional dual-emissive probes, the fluorescence of rhodamine B immobilized in a prepared probe was gradually enhanced at a 585 nm emission wavelength with increasing concentrations of OTC under 405 nm excitation, while OTC also experienced an obvious fluorescence enhancement at a 521 nm emission wavelength due to a molecular conformation transition from the twisted to the extended state, realizing a molecular conformational transition-induced dual fluorescence enhancement for OTC detection under a single excitation wavelength. In addition to the mechanism exploration and double linear range for OTC quantification with nM level detection limits in solution, a paper-based portable test strip was successfully fabricated by loading the probe on glass fiber filter paper with an obvious fluorescence color change from orange to yellow upon increasing the addition of OTC. We expect that the proposed probe in this work would provide an example for the design of organic fluorophore-based sensors exhibiting multiple fluorescence responses under a single excitation.


Assuntos
Oxitetraciclina , Humanos , Antibacterianos , Rodaminas , Corantes Fluorescentes , Conformação Molecular
17.
Mikrochim Acta ; 189(11): 415, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36217040

RESUMO

An enhanced ratiometric fluorescence sensor was built for on-site visual detection of doxycycline (DOX) through the interaction with bovine serum albumin on the surface of red emissive copper nanoclusters. Upon the addition of weakly fluorescent DOX, the red fluorescence from copper nanoclusters gradually decreased through the inner-filter effect (IFE), while a green fluorescence appears and significantly increases, forming an interesting fluorescent isosbestic point, which was assigned to DOX due to sensitization effect of bovine serum albumin. On the basis of this ratiometric fluorescence, the system possessed good limit of detection (LOD) of 45 nM and excellent selectivity for DOX over other tetracyclines. Based on these findings, a paper-based sensor has been fabricated for distinct visual detection of trace DOX and combined with smartphone color recognizer for quantitative detection of DOX (LOD = 83 nM). This method shows broad application prospects in environmental monitoring and food safety.


Assuntos
Cobre , Nanopartículas Metálicas , Antibacterianos , Doxiciclina , Soroalbumina Bovina , Espectrometria de Fluorescência/métodos , Tetraciclinas
18.
Adv Mater ; 34(31): e2200004, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35688799

RESUMO

Transition metal dichalcogenide (TMD) quantum dots (QDs) with defects have attracted interesting chemistry due to the contribution of vacancies to their unique optical, physical, catalytic, and electrical properties. Engineering defined defects into molybdenum sulfide (MoS2 ) QDs is challenging. Herein, by applying a mild biomineralization-assisted bottom-up strategy, blue photoluminescent MoS2 QDs (B-QDs) with a high density of defects are fabricated. The two-stage synthesis begins with a bottom-up synthesis of original MoS2 QDs (O-QDs) through chemical reactions of Mo and sulfide ions, followed by alkaline etching that creates high sulfur-vacancy defects to eventually form B-QDs. Alkaline etching significantly increases the photoluminescence (PL) and photo-oxidation. An increase in defect density is shown to bring about increased active sites and decreased bandgap energy; which is further validated with density functional theory calculations. There is strengthened binding affinity between QDs and O2 due to lower gap energy (∆EST ) between S1 and T1 , accompanied with improved intersystem crossing (ISC) efficiency. Lowered gap energy contributes to assist e- -h+ pair formation and the strengthened binding affinity between QDs and 3 O2 . Defect engineering unravels another dimension of material properties control and can bring fresh new applications to otherwise well characterized TMD nanomaterials.

19.
ACS Appl Mater Interfaces ; 14(22): 25183-25196, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35638599

RESUMO

Chemodynamic therapy (CDT), as a powerful tumor therapeutic approach with low side effects and selective therapeutic efficiency, has gained much attention. However, the low intracellular content of H2O2 and the cellular bottleneck of low intracellular oxidative reaction rates at tumor sites have limited the antitumor efficacy of CDT. Herein, a series of sulfur-deficient engineered biodegradable cobalt sulfide quantum dots (CoSx QDs) were constructed for improved synergistic photothermal- and hyperthermal-enhanced CDT of tumors through regulating the photothermal conversion efficiency (PCE) and Fenton-like activity. Through defect engineering, we modulated the PCE and promoted the Fenton catalytic capability of CoSx QDs. With increasing defect sites, the Fenton-like activity improved to generate more toxic •OH, while the photothermal effect declined slightly. In light of above unique superiorities, the best synergistic effects of CoSx QDs were obtained through comparing their PCE and catalytic activity by regulating the sulfur defect fraction degree in these QDs during the synthetic process. In addition, the ultrasmall size and biodegradation endowed QDs with the ability to be rapidly decomposed to ions that were easily excreted after therapy, thus reducing biogenic accumulation in the body with lowered systemic side effects. The in vitro/vivo results demonstrated that the photothermal- and hyperthermal-enhanced chemodynamic effect of CoSx QDs can enable remarkable anticancer properties with favorable biocompatibility. In this study, the defect-driven mechanism for the photothermal-enhanced Fenton-like reaction provides a flexible strategy to deal with different treatment environments, holding great promise in developing a multifunctional platform for cancer treatment in the future.


Assuntos
Nanopartículas , Neoplasias , Pontos Quânticos , Linhagem Celular Tumoral , Cobalto , Humanos , Peróxido de Hidrogênio/metabolismo , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Enxofre
20.
Bioact Mater ; 18: 471-491, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35415299

RESUMO

Flexible polymeric patches find widespread applications in biomedicine because of their biological and tunable features including excellent patient compliance, superior biocompatibility and biodegradation, as well as high loading capability and permeability of drug. Such polymeric patches are classified into microneedles (MNs), hydrogel, microcapsule, microsphere and fiber depending on the formed morphology. The combination of nanomaterials with polymeric patches allows for improved advantages of increased curative efficacy and lowered systemic toxicity, promoting on-demand and regulated drug administration, thus providing the great potential to their clinic translation. In this review, the category of flexible polymeric patches that are utilized to integrate with nanomaterials is briefly presented and their advantages in bioapplications are further discussed. The applications of nanomaterials embedded polymeric patches in non-cancerous diseases were also systematically reviewed, including diabetes therapy, wound healing, dermatological disease therapy, bone regeneration, cardiac repair, hair repair, obesity therapy and some immune disease therapy. Alternatively, the limitations, latest challenges and future perspectives of such biomedical therapeutic devices are addressed.

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