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1.
Angew Chem Int Ed Engl ; : e202404019, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622071

RESUMO

Accelerating sulfur conversion catalysis to alleviate the shuttle effect has become a novel paradigm for effective Li-S batteries. Although nitrogen-coordinated metal single-atom (M-N4) catalysts have been investigated, further optimizing its utilization rate and catalytic activities is urgently needed for practical applications. Inspired by the natural alveoli tissue with interconnected structure and well-distributed enzyme catalytic sites on the wall for the simultaneously fast diffusion and in-situ catalytic conversion of substrates, here, we proposed the controllable synthesis of bioinspired carbon cathode with interconnected porous structure and asymmetric coordinated V-S1N3 sites for efficient and stable Li-S batteries. The enzyme-mimetic V-S1N3 shows asymmetric electronic distribution and high tunability, therefore enhancing in-situ polysulfide conversion activities. Experimental and theoretical results reveal that the high charge asymmetry degree and large atom radius of S in V-S1N3 result in sloping adsorption for polysulfide, thereby exhibiting low thermodynamic energy barriers and long-range stability (0.076% decay over 600 cycles).

2.
Angew Chem Int Ed Engl ; 63(15): e202400838, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38372011

RESUMO

Developing artificial enzymes based on organic molecules or polymers for reactive oxygen species (ROS)-related catalysis has broad applicability. Herein, inspired by porphyrin-based heme mimics, we report the synthesis of polyphthalocyanine-based conjugated polymers (Fe-PPc-AE) as a new porphyrin-evolving structure to serve as efficient and versatile artificial enzymes for augmented reactive oxygen catalysis. Owing to the structural advantages, such as enhanced π-conjugation networks and π-electron delocalization, promoted electron transfer, and unique Fe-N coordination centers, Fe-PPc-AE showed more efficient ROS-production activity in terms of Vmax and turnover numbers as compared with porphyrin-based conjugated polymers (Fe-PPor-AE), which also surpassed reported state-of-the-art artificial enzymes in their activity. More interestingly, by changing the reaction medium and substrates, Fe-PPc-AE also revealed significantly improved activity and environmental adaptivity in many other ROS-related biocatalytic processes, validating the potential of Fe-PPc-AE to replace conventional (poly)porphyrin-based heme mimics for ROS-related catalysis, biosensors, or biotherapeutics. It is suggested that this study will offer essential guidance for designing artificial enzymes based on organic molecules or polymers.


Assuntos
Heme , Porfirinas , Heme/química , Oxigênio/química , Espécies Reativas de Oxigênio , Porfirinas/química , Catálise , Polímeros
3.
ACS Appl Mater Interfaces ; 15(48): 56213-56222, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37992272

RESUMO

Manipulation of the structure of covalent organic frameworks at the molecular level is an efficient strategy to shift their biological, physicochemical, optical, and electrical properties in the desired windows. In this work, we report on a new method to construct chiral triazine frameworks using metal-driven polymerization for enantiodiscrimination. The nucleophilic substitution reaction between melamine and cyanuric chloride was performed in the presence of PdCl2, ZnCl2, and CuCl2 as chirality-directing agents. Palladium, with the ability of planar complex formation, was able to assemble monomers in two-dimensions and drive the reaction in two directions, leading to a two-dimensional triazine network with several micrometers lateral size. Nonplanar arrangements of monomers in the presence of ZnCl2 and CuCl2, however, resulted in calix and bouquet structures, respectively. While 2D and bouquet structures showed strong negative and positive bands in the CD spectra, respectively, their calix counterparts displayed long-range weak negative bands. In spite of the ability of both calix and bouquet networks to load l-histidine 35 and 50% more than d-histidine from pure enantiomers, respectively, only calix counterparts were able to take up this enantiomer (78%) from the racemic mixture. The two-dimensional polytriazine network did not show any specific interactions with pure enantiomers or their racemic mixtures.

4.
Environ Res ; 238(Pt 1): 117078, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37704076

RESUMO

Synthesis of fully triazine frameworks (C3N3) by metal catalyzed reactions at high temperatures results in carbonized and less-defined structures. Moreover, metal impurities affect the physicochemical, optical and electrical properties of the synthesized frameworks, dramatically. In this work, two-dimensional C3N3 (2DC3N3) has been synthesized by in situ catalyst-free copolymerization of sodium cyanide and cyanuric chloride, as cheap and commercially available precursors, at ambient conditions on gram scale. Reaction between sodium cyanide and cyanuric chloride resulted in electron-poor polyfunctional intermediates, which converted to 2DC3N3 with several hundred micrometers lateral size at ambient conditions upon [2 + 2+2] cyclotrimerization. 2DC3N3 sheets, in bulk and individually, showed strong fluorescence with 63% quantum yield and sensitive to small objects such as dyes and metal ions. The sensitivity of 2DC3N3 emission to foreign objects was used to detect low concentration of water impurities. Due to the high negative surface charge (-37.7 mV) and dispersion in aqueous solutions, they demonstrated a high potential to remove positively charged dyes from water, exemplified by excellent removal efficiency (>99%) for methylene blue. Taking advantage of the straightforward production and strong interactions with dyes and metal ions, 2DC3N3 was integrated in filters and used for the fast detection and efficient removal of water impurities.


Assuntos
Estruturas Metalorgânicas , Poluentes da Água , Cianeto de Sódio , Corantes , Triazinas , Água
5.
Biomed Pharmacother ; 166: 115402, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37660653

RESUMO

A supramolecular redox responsive nanogel (NG) with the ability to sense cancer cells and loaded with a releasing therapeutic agent was synthesized using hostguest interactions between polyethylene glycol-grafted-ß-cyclodextrin and ferrocene boronic acid. Cyclic voltammetry matched with other spectroscopy and microscopy methods provided strong indications regarding host-guest interactions and formation of the NG. Moreover, the biological properties of the NG were evaluated using fluorescence silencing, confocal laser scanning microscopy, and cell toxicity assays. Nanogel with spherical core-shell architecture and 100-200 nm sized nanoparticles showed high encapsulation efficiency for doxorubicin (DOX) and luminol (LU) as therapeutic and sensing agents. High therapeutic and sensing efficiencies were manifested by complete release of DOX and dramatic quenching of LU fluorescence triggered by 0.05 mM H2O2 (as an ROS component). The NGs showed high ROS sensitivity. Taking advantage of a high loading capacity, redox sensitivity, and biocompatibility, the NGs can be used as strong theranostic systems in inflammation-associated diseases.


Assuntos
Peróxido de Hidrogênio , Medicina de Precisão , Nanogéis , Metalocenos , Espécies Reativas de Oxigênio , Doxorrubicina/farmacologia , Microscopia Confocal
6.
Chem Soc Rev ; 52(19): 6838-6881, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37705437

RESUMO

Benefiting from low costs, structural diversities, tunable catalytic activities, feasible modifications, and high stability compared to the natural enzymes, reactive oxygen nanobiocatalysts (RONBCs) have become dominant materials in catalyzing and mediating reactive oxygen species (ROS) for diverse biomedical and biological applications. Decoding the catalytic mechanism and structure-reactivity relationship of RONBCs is critical to guide their future developments. Here, this timely review comprehensively summarizes the recent breakthroughs and future trends in creating and decoding RONBCs. First, the fundamental classification, activity, detection method, and reaction mechanism for biocatalytic ROS generation and elimination have been systematically disclosed. Then, the merits, modulation strategies, structure evolutions, and state-of-art characterisation techniques for designing RONBCs have been briefly outlined. Thereafter, we thoroughly discuss different RONBCs based on the reported major material species, including metal compounds, carbon nanostructures, and organic networks. In particular, we offer particular insights into the coordination microenvironments, bond interactions, reaction pathways, and performance comparisons to disclose the structure-reactivity relationships and mechanisms. In the end, the future challenge and perspectives for RONBCs are also carefully summarised. We envision that this review will provide a comprehensive understanding and guidance for designing ROS-catalytic materials and stimulate the wide utilisation of RONBCs in diverse biomedical and biological applications.

7.
Chem Soc Rev ; 52(20): 7294-7295, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37753775

RESUMO

Correction for 'Reactive oxygen nanobiocatalysts: activity-mechanism disclosures, catalytic center evolutions, and changing states' by Sujiao Cao et al., Chem. Soc. Rev., 2023, https://doi.org/10.1039/d3cs00087g.

8.
ACS Nano ; 17(17): 16501-16516, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37616178

RESUMO

The healing of tendon injury is often hindered by peritendinous adhesion and poor regeneration caused by the accumulation of reactive oxygen species (ROS), development of inflammatory responses, and the deposition of type-III collagen. Herein, an extracellular vesicles (EVs)-cloaked enzymatic nanohybrid (ENEV) was constructed to serve as a multifaceted biocatalyst for ultrasound (US)-augmented tendon matrix reconstruction and immune microenvironment regulation. The ENEV-based biocatalyst exhibits integrated merits for treating tendon injury, including the efficient catalase-mimetic scavenging of ROS in the injured tissue, sustainable release of Zn2+ ions, cellular uptake augmented by US, and immunoregulation induced by EVs. Our study suggests that ENEVs can promote tenocyte proliferation and type-I collagen synthesis at an early stage by protecting tenocytes from ROS attack. The ENEVs also prompted efficient immune regulation, as the polarization of macrophages (Mφ) was reversed from M1φ to M2φ. In a rat Achilles tendon defect model, the ENEVs combined with US treatment significantly promoted functional recovery and matrix reconstruction, restored tendon morphology, suppressed intratendinous scarring, and inhibited peritendinous adhesion. Overall, this study offers an efficient nanomedicine for US-augmented tendon regeneration with improved healing outcomes and provides an alternative strategy to design multifaceted artificial biocatalysts for synergetic tissue regenerative therapies.


Assuntos
Vesículas Extracelulares , Traumatismos dos Tendões , Animais , Ratos , Espécies Reativas de Oxigênio , Colágeno Tipo I , Tendões
9.
Int J Biol Macromol ; 253(Pt 1): 126535, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37634774

RESUMO

Hydrogels with very interesting properties such as high water content, porosity, swelling, and mimicking the structure of the extracellular matrix (ECM) are promising candidates for a variety of applications. Recently, great efforts are being made to improve the shape and functionality of three-dimensional (3D) hydrogels. One of the most promising approaches is the incorporation of metal or metal nanoparticles (NPs) into hydrogels made of natural and synthetic polymers such as proteins, carbohydrates (i.e. chitosan, carboxymethyl cellulose, hyaluronic acid, etc), and the development of dynamic functional hydrogels that have been extensively studied. This review article focuses on the incorporation of metals or metal NPs into hydrogels to enhance their functionality and properties. In the first part, various metal-based hydrogels including metal- coordinated hydrogels, metal-nanocomposite hydrogels, and their synthesis methods are discussed. Subsequently, various properties of metal-containing hydrogels such as mechanical, self-healing, bioadhesion, antibacterial activity, and conductivity are explained. Finally, stimuli-responsive metal-based hydrogels are discussed with a special focus on carbohydrate polymers. This review article presents a new perspective on the development of hydrogels for various biomedical applications.


Assuntos
Quitosana , Nanopartículas Metálicas , Nanocompostos , Polímeros/química , Hidrogéis/química , Nanocompostos/química , Nanopartículas Metálicas/química , Quitosana/química
10.
Daru ; 31(2): 205-219, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37610559

RESUMO

The present study aimed at developing an injectable hydrogel based on acacia gum (AG) for wound healing acceleration. The hydrogels were synthetized through metal-ligand coordination mediated by Fe3+ and characterized in terms of gelation time, gel content, initial water content, swelling capacity, water retention ratio, and porosity. Moreover, FTIR, XRD and TGA analyses were performed for the hydrogels and allantoin (Alla) loaded ones. Furthermore, bioadhessiveness, and self-healing as well as antibacterial, toxicity and wound healing potentials of the hydrogels were evaluated. The hydrogels displayed fast gelation time, high swelling, porosity, and bioadhessiveness, as well as antioxidant, self-healing, antibacterial, blood clotting, and injectability properties. FTIR, XRD and TGA analyses confirmed hydrogel synthesis and drug loading. The Alla-loaded hydrogels accelerated wound healing by decreasing the inflammation and increasing the cell proliferation as well as collagen deposition. Hemocompatibility, cell cytotoxicity, and in vivo toxicity experiments were indicative of a high biocompatibility level for the hydrogels. Given the advantages of fast gelation, injectability and beneficial biological properties, the use of Alla-loaded hydrogels could be considered a new remedy for efficient wound healing.


Assuntos
Goma Arábica , Hidrogéis , Cicatrização , Polissacarídeos , Água , Antibacterianos/farmacologia
11.
J Chromatogr A ; 1705: 464195, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37423076

RESUMO

Various microextraction methods have demonstrated a positive effect when assisted by vacuum. However, working with such systems is often laborious, they often require expensive and non-portable vacuum pumps, and may even suck off some sample vapor or solid particles during the evacuation process. To address these issues, a simple, and affordable vacuum-assisted headspace solid-phase microextraction (HS-SPME) device was developed in this study. The device, named In Syringe Vacuum-assisted HS-SPME (ISV-HS-SPME), utilizes an adjustable 40 mL glass syringe as a vacuum provider and sampling vessel. A new fiber coating, made from a hybrid of covalent triazine-based frameworks and metal-organic frameworks (COF/MOF), was prepared and characterized by Fourier transform infrared spectrometry, field emission scanning electron microscopy, energy dispersive X-ray, X-ray diffraction, thermogravimetric analysis, and Brunauer-Emmett-Teller techniques for use in the ISV-HS-SPME. By optimizing parameters such as extraction temperature, extraction time, desorption temperature, desorption time, and, humidity using a simplex method, the ISV system was found to increase the extraction efficiency of polycyclic aromatic hydrocarbons (PAHs) and benzene, toluene, ethylbenzene, and xylenes (BTEX) in solid samples by up to 175%. The determinations were followed by GC-FID measurements. Compared to three commercially available fibers, the ISV-HS-SPME device with the COF/MOF (2DTP/MIL-101-Cr) fiber exhibited significantly higher peak areas for PAHs and BTEX. The linear dynamic ranges for BTEX and PAHs were 7.1-9000 ng g-1 and 0.23-9000 ng g-1, respectively, with limits of detection ranging from 2.1-5 ng g-1 for BTEX and 0.07-1.6 ng g-1 for PAHs. The relative standard deviation of the method was 2.6-7.8% for BTEX and 1.6-6.7% for PAHs. The ISV-HS-SPME was successfully used to simultaneously determine PAHs and BTEX in polluted soil samples with recoveries ranging from 80.4 to 108%.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Microextração em Fase Sólida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Solo , Limite de Detecção , Tolueno , Benzeno , Xilenos
12.
Adv Sci (Weinh) ; 10(20): e2207759, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37129318

RESUMO

Engineering advanced therapeutic and diagnostic nano-bio-platforms (NBPFs) have emerged as rapidly-developed pathways against a wide range of challenges in antitumor, antipathogen, tissue regeneration, bioimaging, and biosensing applications. Emerged 2D materials have attracted extensive scientific interest as fundamental building blocks or nanostructures among material scientists, chemists, biologists, and doctors due to their advantageous physicochemical and biological properties. This timely review provides a comprehensive summary of creating advanced NBPFs via emerging 2D materials (2D-NBPFs) with unique insights into the corresponding molecularly restructured microenvironments and biofunctionalities. First, it is focused on an up-to-date overview of the synthetic strategies for designing 2D-NBPFs with a cross-comparison of their advantages and disadvantages. After that, the recent key achievements are summarized in tuning the biofunctionalities of 2D-NBPFs via molecularly programmed microenvironments, including physiological stability, biocompatibility, bio-adhesiveness, specific binding to pathogens, broad-spectrum pathogen inhibitors, stimuli-responsive systems, and enzyme-mimetics. Moreover, the representative therapeutic and diagnostic applications of 2D-NBPFs are also discussed with detailed disclosure of their critical design principles and parameters. Finally, current challenges and future research directions are also discussed. Overall, this review will provide cutting-edge and multidisciplinary guidance for accelerating future developments and therapeutic/diagnostic applications of 2D-NBPFs.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Técnicas Biossensoriais/métodos , Nanoestruturas/química
13.
ACS Nano ; 17(3): 2943-2957, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36688804

RESUMO

The microenvironments with high reactive-oxygen-species (ROS) levels, inflammatory responses, and oxidative-stress effects in diabetic ulcer wounds, leading to poor proliferation and differentiation of stem cells, severely inhibit their efficient healing. Here, to overcome the unbalanced multielectron reactions in ROS catalysis, we develop a cobalt selenide-based biocatalyst with an amorphous Ru@CoSe nanolayer for ultrafast and broad-spectrum catalytic ROS-elimination. Owing to the enriched electrons and more unoccupied orbitals of Ru atoms, the amorphous Ru@CoSe nanolayer-equipped biocatalyst displays excellent catalase-like kinetics (maximal reaction velocity, 23.05 µM s-1; turnover number, 2.00 s-1), which exceeds most of the currently reported metal compounds. The theoretical studies show that Ru atoms act as "regulators" to tune the electronic state of the Co sites and modulate the interaction of oxygen intermediates, thus improving the reversible redox properties of active sites. Consequently, the Ru@CoSe can efficiently rescue the proliferation of mesenchymal stem cells and maintain their angiogenic potential in the oxidative stress environment. In vivo experiments reveal the superior ROS-elimination ability of Ru@CoSe on the inflammatory diabetic wound. This study offers an effective nanomedicine for catalytic ROS-scavenging and ultrafast healing of inflammatory wounds and also provides a strategy to design biocatalytic metal compounds via bringing amorphous catalytic structures.


Assuntos
Diabetes Mellitus , Cicatrização , Humanos , Espécies Reativas de Oxigênio , Cicatrização/fisiologia , Estresse Oxidativo , Metais , Oxigênio
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 292: 122397, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36716605

RESUMO

A novel Schiff base-based sensor (L) has been designed, synthesized, and developed as a fluorescent and colorimetric sensor for cyanide and acetate. This L exhibited a quick response with rapid sensitivity to CN- and AcO- through a remarkable color change from yellow to red which was detectable by the naked eyes. It also sensed CN- and AcO- in a fluorescent way via an enhancement in fluorescence intensity. The interaction between L and anions (CN- and AcO-) was investigated by using UV-Vis studies, and 1H NMR titration. The theoretical DFT calculations were also employed to support the results, which displayed good agreement with the experimental value acquisition. As the detection limit for cyanide and acetate were 2.1 × 10-9 M and 1.7 × 10-9 M; respectively, low concentrations of these anions could be detectable in the proposed L sensor. In addition, L showed significant reversibility of CN- detection by using Cu2+ as a proper reagent with two different sensing methods including color change and UV-Vis. Last but not least, L could be applied to rapidly detect CN- in a wide range of pH. As a result, the proposed sensor is promising to identify cyanide and acetate in practical applications in medical, biological, and chemical fields.

15.
J Nanostructure Chem ; : 1-11, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36196295

RESUMO

Two-dimensional polymeric networks are a new class of polymers with interesting physicochemical and biological properties. They promise a wide range of future biomedical applications including pathogen interactions, drug delivery, bioimaging, photothermal, and photodynamic therapy, owing to their unique features, such as high surface area and multivalent interactions at nano-biointerfaces. In this work, a thermosensitive two-dimensional polymeric network consisting poly(N-isopropylacrylamide) (pNIPAM) chains that are mechanically interlocked by a polyglycerol platform was synthesized and used for bacteria incapacitation. Two-dimensional hyperbranched polyglycerol (2D-hPG) was synthesized by a graphene-assisted strategy and used for encapsulation of azobisisobutyronitrile (AIBN). Radical polymerization of N-isopropylacrylamide by encapsulated AIBN resulted in thermoresponsive platforms with ~ 500 nm lateral size and 20-50 nm thickness. Due to its porous structure, 2D-PNPG was able to efficiently load antibiotics, such as tetracycline (TC) and amoxicillin (AMX). The rate of release of antibiotics from 2D-PNPG and the antibacterial activity of the system correlated with the variation of temperature as a result of the thermosensitivity of 2D-PNPG. This study shows that two-dimensional polymers are efficient platforms for future biomedical applications including drug delivery and bacteria incapacitation. Graphical abstract: Thermoresponsive two-dimensional nanomaterials with the ability of loading therapeutic agents and antibacterial activity are synthesized and characterized.

16.
Biomater Adv ; 137: 212820, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35929257

RESUMO

Healing of injured tendon is a major clinical challenge in orthopaedic medicine, due to the poor regenerative potential of this tissue. Two-dimensional nanomaterials, as versatile scaffolds, have shown a great potential to support, trigger and accelerate the tendon regeneration. However, weak mechanical properties, poor functionality and low biocompatibility of these scaffolds as well as post-surgery infections are main drawbacks that limit their development in the higher clinical phases. In this work, a series of hydrogels consisting polyglycerol functionalized reduced graphene oxide (PG), polyglycerol-functionalized molybdenum disulfide (PMoS2) and PG/PMoS2 hybrid within the gelatin matrix are formulated in new scaffolds and their ability for the healing of injured Achilles tendon, due to their high mechanical properties, low toxicity, cell proliferation enhancement, and antibacterial activities is investigated. While scaffolds containing PG and PMoS2 showed a moderate tendon regeneration and anti-inflammatory effect, respectively, their hybridization into PG/PMoS2 demonstrated a synergistic healing efficiency. Along the same line, an accelerated return of tendon function with low peritendinous adhesion and low cross-sectional area in animal group treated with scaffold containing PG/PMoS2 was observed. Taking advantage of the high biocompatibility, high strength, straightforward construction and fast tendon regeneration, PG/PMoS2 can be used as a new scaffold for the future tissue engineering.


Assuntos
Tendão do Calcâneo , Grafite , Traumatismos dos Tendões , Tendão do Calcâneo/cirurgia , Animais , Grafite/farmacologia , Hidrogéis/farmacologia , Molibdênio , Traumatismos dos Tendões/cirurgia , Tecidos Suporte
17.
Int J Nanomedicine ; 16: 5955-5980, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34511900

RESUMO

Two-dimensional nanomaterials are emerging as promising candidates for a wide range of biomedical applications including tissue engineering, biosensing, pathogen incapacitation, wound healing, and gene and drug delivery. Graphene, due to its high surface area, photothermal property, high loading capacity, and efficient cellular uptake, is at the forefront of these materials and plays a key role in this multidisciplinary research field. Poor water dispersibility and low functionality of graphene, however, hamper its hybridization into new nanostructures for future nanomedicine. Functionalization of graphene, either by covalent or non-covalent methods, is the most useful strategy to improve its dispersion in water and functionality as well as processability into new materials and devices. In this review, recent advances in functionalization of graphene derivatives by different (macro)molecules for future biomedical applications are reported and explained. In particular, hydrophilic functionalization of graphene and graphene oxide (GO) to improve their water dispersibility and physicochemical properties is discussed. We have focused on the anticancer drug delivery of polyfunctional graphene sheets.


Assuntos
Antineoplásicos , Grafite , Nanoestruturas , Sistemas de Liberação de Medicamentos , Nanomedicina
18.
Macromol Biosci ; 21(11): e2100233, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34411417

RESUMO

2D MoS2 has shown a great potential in biomedical applications, due to its superior loading capacity, photothermal property, and biodegradation. In this work, polyglycerol functionalized MoS2 nanosheets with photothermal and pH dual-stimuli responsive properties are used for the co-delivery of doxorubicin and chloroquine and treatment of multidrug-resistant HeLa (HeLa-R) cells. The polyglycerol functionalized MoS2 nanosheets with 80 nm average size show a high biocompatibility and loading efficiency (≈90%) for both drugs. The release of drugs from the nanosheets at pH 5.5 is significantly promoted by laser irradiation leading to efficient destruction of incubated HeLa-R cells. In vitro evaluation shows that the designed nanoplatform has a high ability to kill HeLa-R cells. Confocal experiments demonstrate that the synthesized drug delivery system enhances the cellular uptake of DOX via folic acid targeting ligand. Taking advantage of the combined properties including biocompatibility and targeting ability as well as high loading capacity and photothermal release, this multifunctional nanosystem is a promising candidate for anticancer therapy.


Assuntos
Cloroquina/administração & dosagem , Dissulfetos/administração & dosagem , Doxorrubicina/administração & dosagem , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glicerol/administração & dosagem , Molibdênio/administração & dosagem , Nanoestruturas/administração & dosagem , Neoplasias/tratamento farmacológico , Polímeros/administração & dosagem , Células HeLa , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectrofotometria Ultravioleta
19.
Adv Funct Mater ; 31(22): 2009003, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34230823

RESUMO

2D nanomaterials have garnered widespread attention in biomedicine and bioengineering due to their unique physicochemical properties. However, poor functionality, low solubility, intrinsic toxicity, and nonspecific interactions at biointerfaces have hampered their application in vivo. Here, biocompatible polyglycerol units are crosslinked in two dimensions using a graphene-assisted strategy leading to highly functional and water-soluble polyglycerols nanosheets with 263 ± 53 nm and 2.7 ± 0.2 nm average lateral size and thickness, respectively. A single-layer hyperbranched polyglycerol containing azide functional groups is covalently conjugated to the surface of a functional graphene template through pH-sensitive linkers. Then, lateral crosslinking of polyglycerol units is carried out by loading tripropargylamine on the surface of graphene followed by lifting off this reagent for an on-face click reaction. Subsequently, the polyglycerol nanosheets are detached from the surface of graphene by slight acidification and centrifugation and is sulfated to mimic heparin sulfate proteoglycans. To highlight the impact of the two-dimensionality of the synthesized polyglycerol sulfate nanosheets at nanobiointerfaces, their efficiency with respect to herpes simplex virus type 1 and severe acute respiratory syndrome corona virus 2 inhibition is compared to their 3D nanogel analogs. Four times stronger in virus inhibition suggests that 2D polyglycerols are superior to their current 3D counterparts.

20.
Int J Biol Macromol ; 182: 2048-2055, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34087295

RESUMO

Two-dimensional MoS2 is emerging as a unique platform for a wide range of biomedical applications including extracellular matrix mimics, drug delivery systems and antimicrobial agents. However, low processability and nonspecific interactions at biointerfaces are serious challenges that hamper the biomedical applications of this nanomaterial. Herein, we show how specific interactions between MoS2 and a gelatin matrix results in a biomimetic hydrogel with the self-healing and molecular recognition properties. ß-Cyclodextrin was conjugated to the surface of freshly exfoliated MoS2 through a one pot nucleophilic substitution reaction and the obtained cyclodextrin-functionalized MoS2 was used to construct an injectable, self-healable and flexible supramolecular hydrogel upon host-guest interactions with adamantane-modified gelatin matrix. Incorporation of almost 1 wt% of CDMoS2 into gelatin matrix with 1cm2 cross-section resulted in a hydrogel that was able to tolerate one hundred grams. Also, storage modulus (G'), loss modulus (G″) of the obtained hydrogel was 10 and 25 times higher than that for the neat gelatin, respectively. Due to its self-healing, molecular recognition and mechanical properties as well as its flexibility, injectability, and processability, MoS2gel is a promising candidate for a wide range of future biomedical applications including extracellular matrix mimics and tissue engineering.


Assuntos
Dissulfetos/química , Gelatina/química , Hidrogéis/química , Molibdênio/química , Animais , Reologia , Suínos , Difração de Raios X , beta-Ciclodextrinas/química
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