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1.
ACS Omega ; 9(9): 10782-10792, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38463299

RESUMO

Jinguanchong deposit, a part of the Mingyuefeng ore field in eastern Hunan Province, China, is a typical perigranitic uranium deposit (a subtype of granite-related deposit) discovered recently with considerable uranium mineralization. Herein, uraninite, the primary ore mineral in the deposit, was investigated via scanning electron microscopy and electron probe microanalysis. Additionally, laser ablation-inductively coupled plasma-mass spectrometry was used for the first time to determine the in situ U-Pb age and the rare-earth element characteristics of uraninite. Uraninite mainly comprises UO2, CaO, and PbO with a low ThO2 content. Uraninite exhibits a low total content of rare-earth elements with a distinct fractionation between light and heavy rare-earth elements while displaying a negative Eu anomaly. The presence of major elements and rare-earth elements in uraninite suggests its formation within a hydrothermal environment at moderate to low temperatures below 350 °C, thereby classifying the Jinguanchong deposit as a typical hydrothermal vein-type uranium deposit. The uranium metallogenic age is determined to be 93.8 ± 1.4 Ma, falling within the midlate Cretaceous period. This age corresponds to the Mesozoic lithospheric extension and thinning events (approximately 85-95 Ma) in South China, suggesting that the formation of the Jinguanchong uranium deposit might be associated with the tectonic dynamics of lithospheric extension and thinning.

2.
ACS Nano ; 17(5): 4463-4473, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36802559

RESUMO

Simultaneous imaging of exogenous nanomaterials and endogenous metabolites in situ remains challenging and is beneficial for a systemic understanding of the biological behavior of nanomaterials at the molecular level. Here, combined with label-free mass spectrometry imaging, visualization and quantification of the aggregation-induced emission nanoparticles (NPs) in tissue were realized as well as related endogenous spatial metabolic changes simultaneously. Our approach enables us to identify the heterogeneous deposition and clearance behavior of nanoparticles in organs. The accumulation of nanoparticles in normal tissues results in distinct endogenous metabolic changes such as oxidative stress as indicated by glutathione depletion. The low passive delivery efficiency of nanoparticles to tumor foci suggested that the enrichment of NPs in tumors did not benefit from the abundant tumor vessels. Moreover, spatial-selective metabolic changes upon NPs mediated photodynamic therapy was identified, which enables understanding of the NPs induced apoptosis in the process of cancer therapy. This strategy allows us to simultaneously detect exogenous nanomaterials and endogenous metabolites in situ, hence to decipher spatial selective metabolic changes in drug delivery and cancer therapy processes.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Sistemas de Liberação de Medicamentos , Fotoquimioterapia/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Nanopartículas/química , Imagem Óptica/métodos , Linhagem Celular Tumoral
3.
Front Psychol ; 14: 1217014, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38440371

RESUMO

The effects of short movies on social media platforms are gaining worldwide popularity and are now attracting global academic attention. Employing self-perception theory and qualitative research methodology, the study examines the influence of short video applications (TikTok) on app-user engagement and evaluates the self-perceived cognitive psychological understanding of Chinese university students. The findings show that identity, attitude change, emotional perception, and civic engagement are the most influential aspects of Chinese youths' self-perceptions. Furthermore, the positive and negative correlated components influence the distribution of short video values. Such tactical use of personality construction contributes to the present psychological research of Chinese university students.

4.
Front Pain Res (Lausanne) ; 4: 1233444, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38179224

RESUMO

Introduction: Neuropathic Pain (NP) is often accompanied by mood disorders, which seriously affect the quality of life of patients. This study aimed to analyze the hotspots and trends in NP-related mood disorder research using bibliometric methods and to provide valuable predictions for future research in this field. Methods: Articles and review articles on NP-related mood disorders published from January 2003 to May 2023 were retrieved from the Web of Science Core Collection. We used CiteSpace to analyze publications, countries, institutions, authors, cited authors, journals, cited journals, references, cited references, and keywords. We also analyzed collaborative network maps and co-occurrence network maps. Results: A total of 4,540 studies were collected for analysis. The number of publications concerning NP-related mood disorders every year shows an upward trend. The United States was a major contributor in this field. The University of Toronto was the most productive core institution. C GHELARDINI was the most prolific author, and RH DWORKIN was the most frequently cited author. PAIN was identified as the journal with the highest productivity and citation rate. The current research hotspots mainly included quality of life, efficacy, double-blind methodology, gabapentin, pregabalin, postherpetic neuralgia, and central sensitization. The frontiers in research mainly focused on the mechanisms associated with microglia activation, oxidative stress, neuroinflammation, and NP-related mood disorders. Discussion: In conclusion, the present study provided insight into the current state and trends in NP-related mood disorder research over the past 20 years. Consequently, researchers will be able to identify new perspectives on potential collaborators and cooperative institutions, hot topics, and research frontiers in this field.

5.
Mater Today Bio ; 16: 100411, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36186845

RESUMO

Bimetallic nanozymes have been emerging as essential catalysts due to their unique physicochemical properties from the monometallics. However, the access to optimize catalytic performance is often limited by the thermodynamic immiscibility and also heterogeneity. Thus, we present a one-step coreduction strategy to prepare the miscible Cu-Pd bimetallic nanozymes with controllable shape and homogeneously alloyed structure. The homogeneity is systematically explored and luckily, the homogeneous introduction of Cu successfully endows Cu-Pd bimetallic nanozymes with enhanced Fenton-like efficiency. Density functional theory (DFT) theoretical calculation reveals that Cu-Pd bimetallic nanozymes exhibit smaller d-band center compared with Pd nanozymes. Easier adsorption of H2O2 molecular contributed by the electronic structure of Cu significantly accelerate the catalytic process together with the strong repulsive interaction between H atom and Pd atom. In vitro cytotoxicity and intracellular ROS generation performance reveal the potential for in vivo biocatalysis. The strategy to construct kinetically miscible Cu-Pd bimetallic nanozymes will guide the development of bimetallic catalysts with excellent Fenton-like efficiency for biocatalytic nanomedicine.

6.
ACS Appl Mater Interfaces ; 14(2): 3485-3495, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34994541

RESUMO

The dynamic reversible Diels-Alder (DA) reactions play essential roles in both academic and applied fields. Currently, in situ visualization and direct monitoring of the formation and cleavage of covalent bonds in DA reactions are hampered by finite compatibility and expensive precise instruments, especially limited in solid reactions. We herein report a fluorescence system capable of in situ visualization by naked eyes and monitoring DA/retro-DA reactions. With the fluorescence quenching effect, the synthesized TPEMI could work as an innovative self-indicator for both DA termination and retro-DA occurrence. The fluorescence increases during DA reactions, and the mechanism is investigated to establish qualitative and quantitative relations. Besides rapid screening of reaction conditions and monitoring of DA exchange processes, the TPEMI fluorescence system can visualize heterogeneous and solid-state reactions with the AIE character. The TPEMI platform is expected to offer novel insights into reversible DA processes and dynamic covalent chemistry.

7.
Adv Sci (Weinh) ; 9(4): e2104101, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34898054

RESUMO

As a noninvasive therapeutic technique, photodynamic therapy (PDT) has attracted numerous research interests for cancer therapy. Nevertheless, the residual photosensitizers (PSs) still produce reactive oxygen species (ROS) and damage normal cells under sunlight after PDT, which limits their practical application in clinic. Herein, the authors propose a self-degradable type-I PS based on conjugated polymer, which is composed of aggregation-induced emission (AIE) and imidazole units. Due to the effective conjugated skeleton and unique AIE properties, thus-obtained polymers can effectively generate superoxide radical (O2-• ) through the type-I process under light irradiation, which is ideal for hypoxic tumors treatment. Intriguingly, under light irradiation, O2-• produced by the conjugated polymers can further lead to the self-degradation of the polymer to form nontoxic micro-molecules. It not only helps to resolve the potential phototoxicity problems of residual PSs, but also can accelerate the metabolism of the conjugated polymers to avoid the potential biotoxicity of drug accumulation. This work develops a self-degradable type-I PS, which can turn off the generation of ROS in time after PDT, providing a novel strategy to balance the PDT effect and postoperative safety.


Assuntos
Neoplasias/terapia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/metabolismo , Polímeros/metabolismo , Complicações Pós-Operatórias/prevenção & controle , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Reprodutibilidade dos Testes
8.
Mater Sci Eng C Mater Biol Appl ; 118: 111437, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255030

RESUMO

Multicomponent reactions (MCRs) have attracted broad interest for preparation of functional nanomaterials especially for the synthesis of functional polymers. Herein, we utilized an "old" MCR, the four-component Ugi reaction, to synthesize disulfide bond containing poly(PEG-TPE-DTDPA) amphiphilic copolymers with aggregation-induced emission (AIE) feature. This four-component Ugi reaction was carried out under rather mild reaction conditions, such as room temperature, no gas protection and absent of catalysts. The amphiphilic poly(PEG-TPE-DTDPA) copolymers with high number-average molecular weight (up to 86,440 Da) can self-assemble into claviform fluorescent polymeric nanoparticles (FPNs) in aqueous solution, and these water-dispersed nanoparticles exhibited strong emission, large Stokes shift (142 nm), low toxicity and remarkable ability in cellular imaging. Moreover, owing to the introduction of 3,3'-dithiodipropionic acid with disulfide bond, the resultant AIE-active poly(PEG-TPE-DTDPA) could display reduction-responsiveness and be utilized for synthesis of photothermal agents in-situ. Therefore, the AIE-active poly(PEG-TPE-DTDPA) could be promising for controlled intracellular delivery of biological activity molecules and fabrication of multifunctional AIE-active materials. Therefore, these novel AIE-active polymeric nanoparticles could be of great potential for various biomedical applications, such as biological imaging, stimuli-responsive drug delivery and theranostic applications.


Assuntos
Nanopartículas , Polímeros , Catálise , Dissulfetos , Corantes Fluorescentes
9.
Mater Sci Eng C Mater Biol Appl ; 109: 110442, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228901

RESUMO

Carbon nanotubes (CNTs) are a novel type of one-dimensional carbon nanomaterials that have been widely utilized for biomedical applications such as drug delivery, cancer photothermal treatment owing to their high surface area and unique interaction with cell membranes. However, their biomedical applications are still impeded by some drawbacks, including poor water dispersibility, lack of functional groups and toxicity. Therefore, surface modification of CNTs to overcome these issues should be importance and of great interest. In this work, we reported for the first time that CNTs could be surface modification through the combination of Diels-Alder (D-A) reaction and redox polymerization, this strategy shows the advantages of mild reaction conditions, water tolerance, low temperature and hydroxyl-surfaced initiator. In this modification procedure, the hydroxyl groups were introduced on the surface of CNTs through the D-A reaction that was adopted for grafting the copolymers, which were initiated by the Ce(IV)/HNO3 redox system using the hydrophilic and biocompatible poly(ethylene glycol) methyl ether methacrylate (PEGMA) and carboxyl-rich acrylic acid (AA) as monomers. The final CNTs-OH-PAA@PEGMA composites were characterized by a series of characterization techniques. The drug loading and release results suggested that anticancer agent cis­platinum (CDDP) could be loaded on CNTs-OH-PAA@PEGMA composites through coordination with carboxyl groups and drug release behavior could be controlled by pH. More importantly, the cell viability results clearly demonstrated that CNTs-OH-PAA@PEGMA composites displayed low toxicity and the drug could be transported in cells and still maintain their therapeutic effects.


Assuntos
Nanotubos de Carbono/química , Polímeros/química , Antineoplásicos/química , Reação de Cicloadição , Metacrilatos/química , Oxirredução , Polietilenoglicóis/química , Polimerização
10.
Mater Sci Eng C Mater Biol Appl ; 111: 110804, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279750

RESUMO

Halloysite nanotubes (HNTs) are a kind of aluminosilicate clay with a unique hollow tubular structure that has been intensively explored for various applications especially in biomedical fields owing to their excellent biocompatibility, biodegrading potential and low cost. Surface modification of HNTs with functional polymers will greatly improve their properties and endow new functions for biomedical applications. In this work, a light-induced reversible addition-fragmentation chain transfer (RAFT) polymerization was introduced to successfully prepare HNTs based fluorescent HNTs/poly(PEGMA-Fl) composites in the presence of oxygen using diacrylate-fluorescein and poly (ethylene glycol) methyl ether methacrylate (PEGMA) as the monomers. Without other catalysts, heating, and deoxygenation procedure, the polymerization process can take place under mild conditions. Besides, owing to the introduction of fluorescein and PEGMA on the surface of HNTs, the resultant HNTs/poly(PEGMA-Fl) composites display high water dispersibility and stable fluorescence. The results from cell viability examination and confocal laser scanning microscopy also demonstrated that HNTs/poly(PEGMA-Fl) composites could be internalized by L929 cells with bright fluorescence and low cytotoxicity. Taken together, we developed a novel photo-initiated RAFT polymerization method for the fabrication of HNTs based fluorescent polymeric composites with great potential for biomedical applications. More importantly, many other multifunctional HNTs based polymer composites could also be fabricated through a similar strategy owing to good designability of RAFT polymerization.


Assuntos
Argila/química , Imageamento Tridimensional , Luz , Metais/química , Nanotubos/química , Polimerização/efeitos da radiação , Polímeros/química , Animais , Linhagem Celular , Sobrevivência Celular , Fluorescência , Metacrilatos/química , Camundongos , Nanotubos/ultraestrutura , Polietilenoglicóis/química , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Termogravimetria
11.
J Colloid Interface Sci ; 567: 136-144, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32045735

RESUMO

Fluorescence imaging and magnetic resonance imaging have been research hotspots for adjuvant therapy and diagnosis. However, traditional fluorescent probes or contrast agents possess insurmountable weaknesses. In this work, we reported the preparation of dual-mode probes based on mesoporous silica nanomaterials (MSNs), which were doped with an aggregation-induced emission (AIE) dye and Gd3+ through a direct sol-gel method. In this system, the obtained materials emitted strong red fluorescence, in which the maximum emission wavelength was located at 669 nm, and could be applied as effective fluorescence probes for fluorescence microscopy imaging. Furthermore, the introduction of Gd3+ made the nanoparticles effective contrast agents when applied in contrast-enhanced magnetic resonance (MR) imaging because they could improve the contrast of MR imaging. The excellent biocompatibility of these nanoparticles, as demonstrated via a typical CCK-8 assay, and their performance in fluorescence cell imaging and MR imaging shows their potential for applications in biomedical imaging.


Assuntos
Corantes Fluorescentes/química , Gadolínio/química , Imageamento por Ressonância Magnética , Nanopartículas/química , Imagem Óptica , Dióxido de Silício/química , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Linhagem Celular , Sobrevivência Celular , Meios de Contraste/química , Fluorescência , Corantes Fluorescentes/síntese química , Humanos , Camundongos , Microscopia de Fluorescência , Estrutura Molecular , Tamanho da Partícula , Porosidade , Propriedades de Superfície
12.
Nanoscale ; 12(6): 3574-3592, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32016223

RESUMO

MXenes are a new type of two-dimensional (2D) transition metal carbide or carbonitride material with a 2D structure similar to graphene. The general formula of MXenes is Mn+1XnTx, in which M is an early transition metal element, X represents carbon, nitrogen and boron, and T is a surface oxygen-containing or fluorine-containing group. These novel 2D materials possess a unique 2D layered structure, large specific surface area, good conductivity, stability, and mechanical properties. Benefitting from these properties, MXenes have received increasing attention and emerged as new substrate materials for exploration of various applications including, energy storage and conversion, photothermal treatment, drug delivery, environmental adsorption and catalytic degradation. The progress on various applications of MXene-based materials has been reviewed; while only a few of them covered environmental remediation, surface modification of MXenes has never been highlighted. In this review, we highlight recent advances and achievements in surface modification and environmental applications (such as environmental adsorption and catalytic degradation) of MXene-based materials. The current studies on the biocompatibility and toxicity of MXenes and related materials are summarized in the following sections. The challenges and future directions of the environmental applications of MXene-based materials are also discussed and highlighted.

13.
J Colloid Interface Sci ; 567: 190-201, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32058169

RESUMO

Herein a simple and novel approach has been developed for surface modification of delaminate MXene with nano-mixed silver oxide which combined with mussel-inspired chemistry. Surface modification with dopamine as a secondary reaction platform for loading nano-silver compounds for removal of iodine was achieved. The internal structure and morphology were characterized by SEM and TEM. The element content and distribution analysis of EDS and XPS proved that nano silver compounds were successfully supported and uniformly dispersed on the surface of MXene. Then the adsorption batch experiment was carried out, adsorption time, pH and other factors on the adsorption performance of the adsorbents were studied in details. By calculating the enthalpy change, Gibbs free energy and thermodynamic parameters, the adsorption reaction was found to be an exothermic process. The adsorption kinetics measured the maximum adsorption capacity of 80 mg/g and the removal efficiency is as high as 80% and the adsorption equilibrium time has also been improved. The adsorption kinetics were well fitted by pseudo first-order and second-order models. All the above results demonstrated that the composite from mussel-inspired chemistry has excellent adsorption properties towards iodine ions. This study not only deepens the research on the adsorption behavior of iodine adsorption, but also provides new research directions and experimental methods for pseudo-iodine adsorption.

14.
Mater Sci Eng C Mater Biol Appl ; 108: 110413, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923965

RESUMO

Nanodiamond (ND) has been widely studied as a new type of carbon nanomaterials that is expected to be used as a promising candidate in various fields especially in the field of biomedicine. However, its poor water dispersibility and insufficient controlled release limit its practical applications. In this paper, ND-based composites with pH-responsive hydrazone bonds were successfully prepared by a simple chemical reaction between ester groups and hydrazine hydrate, in which ester groups were conjugated on the surface of ND via thiol-ene click reaction. On the other hand, CHO-PEG and doxorubicin hydrochloride (DOX) were linked on the carriers through formation of hydrazone bonds, resulting in improving water dispersibility and high drug loading capacity. The structure, thermal stability, surface morphology and particle size of ND carriers were characterized by different equipment. Results demonstrated that we have successfully prepared these functionalized ND. The release rate of DOX in acidic environment was significantly greater than that in normal physiological environment. More importantly, cell viability and optical imaging results showed that ND-based composites possess good biocompatibility, therapeutic effect, and could successfully transport DOX to HepG2 cells. Considering the above results, we believe that our new ND carriers will become promising candidates for intracellular controlled drug delivery and cancer treatment.


Assuntos
Doxorrubicina/química , Doxorrubicina/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Nanodiamantes/química , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética
15.
Mater Sci Eng C Mater Biol Appl ; 108: 110376, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924027

RESUMO

As potential alternatives to conventional semiconductor quantum dots, fluorescent carbon quantum dots (CQDs) have received increasing research attention in biomedical fields owing to their splendid advantages of low cytotoxicity, strong fluorescence and excellent water dispersion. However, the preparation procedures of CQDs with designable chemical properties and functions are complicated and low efficient. In this work, we developed a facile, economical and straightforward strategy to prepare CQDs by a one-step thiol-ene click reaction between multiwalled carbon nanotubes (CNTs) and thiomalic acid (TA). The successful synthesis of CQDs was confirmed by a series of characterization data. The results manifested that CQDs were well combined with TA through surface thiol-ene click chemistry. In addition, the optical property is also desirable, the maximum emission wavelength was located in 500 nm and CQDs still could emit strong blue fluorescent light after irradiation with UV irradiation for 3 h. Besides, the pH value makes no significant changes for fluorescence emission wavelength of CQDs and CQDs can emit strongest fluorescence in weak acid solution. Furthermore, CQDs could be internalized by cells and show great cell dyeing performance and low cytotoxicity. All these features imply that TA functionalized CQDs possess great potential for biological imaging. The one-step thiol-ene click strategy provided a novel tool to prepare functionalized CQDs with great potential for biomedical applications.


Assuntos
Química Click/métodos , Nanotubos de Carbono/química , Pontos Quânticos/química , Animais , Morte Celular , Linhagem Celular , Fluorescência , Camundongos , Nanotubos de Carbono/ultraestrutura , Espectroscopia de Prótons por Ressonância Magnética , Pontos Quânticos/ultraestrutura
16.
Mater Sci Eng C Mater Biol Appl ; 106: 110297, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753408

RESUMO

Fluorescent nanodiamond (ND) has been regarded as one of the most promising fluorescent nanoprobes owing to their chemical inert, biocompatibility, optical properties, and rich surface chemistry. The fluorescent ND has been mainly fabricated through high-energy ion beam irradiation of type Ib diamonds and subsequent thermal annealing. The generation of nitrogen-vacancy centers is the reason for the fluorescence. However, the physical method is relatively complicated and it need to expensive equipment as well as high cost. On the other hand, the resultant fluorescent ND particles are lack of functional groups and difficult to be dispersed in aqueous solution. Therefore, the development of facile methods to direct preparation of fluorescent ND and surface modification with functional polymers is of great research interest for expanding the biomedical applications of fluorescent ND. In this report, a facile strategy was reported for the first time to prepare hydrophilic polymers functionalized fluorescent ND (named as ND-PhE-PETOx) composites through the ring-opening polymerization and simultaneous simple nucleophilic substitution reaction using the non-fluorescent detonation ND as the raw material. The obtained fluorescent ND composites were characterized by various characterization techniques in details. The as-obtained ND-PhE-PETOx composites exhibit high water dispersibility, low toxicity and strong fluorescence intensity. Cell uptake results indicating that the fluorescent ND based composites can be effectively internalized by cells. Taken together, we have developed a novel and simple method for the preparation of fluorescent ND based composites, which show excellent physicochemical properties and great potential for biomedical applications.


Assuntos
Corantes Fluorescentes/química , Nanodiamantes/química , Nanopartículas/química , Polímeros/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Microscopia Confocal , Nanopartículas/metabolismo , Nanopartículas/toxicidade , Tamanho da Partícula , Polimerização , Água/química
17.
Nanoscale ; 12(3): 1325-1338, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31872839

RESUMO

MXenes, as a novel kind of two-dimensional (2D) materials, were first discovered by Gogotsi et al. in 2011. Owing to their multifarious chemical compositions and outstanding physicochemical properties, the novel types of 2D materials have attracted intensive research interest for potential applications in various fields such as energy storage and conversion, environmental remediation, catalysis, and biomedicine. Although many achievements have been made in recent years, there still remains a lack of reviews to summarize these recent advances of MXenes, especially in biomedical fields. Understanding the current status of surface modification, biomedical applications and toxicity of MXenes and related materials will give some inspiration to the development of novel methods for the preparation of multifunctional MXene-based materials and promote the practical biomedical applications of MXenes and related materials. In this review, we present the recent developments in the surface modification of MXenes and the biomedical applications of MXene-based materials. In the first section, some typical surface modification strategies were introduced and the related issues were also discussed. Then, the potential biomedical applications (such as biosensor, biological imaging, photothermal therapy, drug delivery, theranostic nanoplatforms, and antibacterial agents) of MXenes and related materials were summarized and highlighted in the following sections. In the last section, the toxicity and biocompatibility of MXenes in vitro were mentioned. Finally, the development, future directions and challenges about the surface modification of MXene-based materials for biomedical applications were discussed. We believe that this review article will attract great interest from the scientists in materials, chemistry, biomedicine and related fields and promote the development of MXenes and related materials for biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Animais , Antibacterianos , Técnicas Biossensoriais , Sistemas de Liberação de Medicamentos , Humanos , Hipertermia Induzida , Fototerapia , Propriedades de Superfície , Nanomedicina Teranóstica
18.
Mater Sci Eng C Mater Biol Appl ; 106: 110157, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753361

RESUMO

Surface modification of carbon nanotubes (CNTs) through controlled living polymerization has demonstrated to be a useful route for preparation of CNTs based polymer composites. However, surface oxidation of CNTs is often required to generate functional groups, which can be further utilized for immobilization of polymerization initiator and grafting polymers. The surface oxidation procedure is rather complex, high energy cost, low efficient and will destroy the structure of CNTs. Therefore, the development of simple and efficient strategies for preparation of CNTs based composites should be of great research interest and raised much attention recently. In this work, a novel mussel inspired strategy that combination of ATRP and ring-opening reaction has been developed for simultaneous preparation of glycosylated and PEGylated CNTs for the first time. CNTs were first coated with polydopamine (PDA) through self-polymerization of dopamine under alkaline aqueous solution. Then polymerization initiator was immobilized on CNT-PDA through simple esterification and amidation reaction to obtain CNT-PDA-Br. The PEGylated CNTs were synthesized through ATRP using CNT-PDA-Br as initiator and polyethylene glycol monoester acrylate and itaconic anhydride (IA) as the monomers. Finally, glucosamine was conjugated with IA via ring-opening reaction. The successful preparation of glycosylated and PEGylated CNTs (CNT-PDA-Poly(PEGMA-co-IA)-Glu) was confirmed by a number of characterization techniques in details. The obtained CNTs based composites showed improved aqueous dispersibility and desirable cytocompatibility, implying their biomedical application potential. As compared with the conventional covalent strategies, the mussel inspired method described in this work will not destroy the structure for introduction functional groups on the surface of CNTs, that can occur under rather mild experimental conditions, including room temperature, short reaction time and aqueous solution. On the other hand, the mussel inspired chemistry can also be used for surface modification of almost any materials regardless of their size, morphology and compositions. Therefore, we believe that the mussel inspired strategy should be a general method for fabrication of various polymer composites for different applications.


Assuntos
Nanotubos de Carbono/química , Polietilenoglicóis/química , Células A549 , Sobrevivência Celular/efeitos dos fármacos , Glucosamina/química , Glicosilação , Humanos , Indóis/química , Nanocompostos/química , Nanocompostos/toxicidade , Nanotubos de Carbono/toxicidade , Polimerização , Polímeros/química , Propriedades de Superfície
19.
Mater Sci Eng C Mater Biol Appl ; 104: 109976, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499989

RESUMO

The preparation of fluorescent inorganic-organic polymer composites for biomedical applications has become one of the most interest research focuses recently. In this work, we reported a novel method for the preparation of Tb3+-doped luminescent layered double hydroxides (LDHs) based composites by taken advantage of a one-pot supramolecular chemistry. The adamantane can be immobilized on the surface of Tb3+-doped LDHs to obtain LDH-Ad, which could be further utilized for modified by the ß-cyclodextrin (ß-CD) containing hyperbranched polyglycerols (ß-CD-HPG) through the host-guest interaction. Based on the characterization results, we demonstrated that the hyperbranched polyglycerol could be facilely introduced on these fluorescent Tb3+-doped LDHs through the method described in this work. The obtained Tb3+-doped LDHs based polymer composites (LDHs-ß-CD-HPG) display improved water dispersibility and still maintain their fluorescence. The results based on various biological assays suggest that LDHs-ß-CD-HPG polymer composites are of low cytotoxicity and their cell uptake behavior can be effectively traced using confocal laser imaging. All of the above results demonstrated that the fluorescent Tb3+-doped LDHs based polymer composites could be effectively surface modified with hydrophilic hyperbranched polymers through a one-pot facile host-guest interaction and the resultant fluorescent composites are of excellent physicochemical properties and display great potential for biomedical applications. This novel surface modification method should also be important for fabrication of other multifunctional composites and therefore great advanced the development of biomedical applications of fluorescent LDHs based polymer composites and related materials.


Assuntos
Glicerol/química , Hidróxidos/química , Polímeros/química , Térbio/química , Celulose/química , Corantes/química , Ciclodextrinas/química , Fluorescência , Interações Hidrofóbicas e Hidrofílicas , Luminescência , Polimerização , Água/química , beta-Ciclodextrinas/química
20.
Carbohydr Polym ; 223: 115102, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426952

RESUMO

Cellulose nanocrystals (CNCs) are a novel type of natural nanomaterials that have attracted tremendous research interest for various applications especially in the biomedical fields owing to their natural origin, biodegradable potential, remarkable biocompatibility and massive reactive hydroxyl groups. In this work, a novel strategy has been developed for fabrication of luminescent CNCs with aggregation-induced emission (AIE) feature for the first time through a facile one-step Ce(IV) redox polymerization for direct surface grafting of AIE dye (PhE) and hydrophilic monomer Poly(ethylene glycol) monomethyl ether acrylate (PEGMA) on CNCs. Various characterization techniques would demonstrate the successful preparation of resultant CNC-PhE-PEGMA with uniform nanoscale size, remarkable fluorescent properties and extremely low cytotoxicity. Furthermore, compared with conventional modification strategy of CNCs, Ce(IV) redox polymerization only need moderate temperature and can operate in aqueous solution utilizing surface hydroxyl groups of CNCs as polymerization activity sites. More importantly, CNC-PhE-PEGMA show desirable fluorescent properties and can be used for cell dyeing, indicating their potential for biomedical applications.

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