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1.
Acc Chem Res ; 56(6): 631-643, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36892059

RESUMO

Delivering biological effector molecules in cultured cells is of fundamental importance to any study or application in which the modulation of gene expression is required. Examples range from generating engineered cell lines for studying gene function to the engineering of cells for cell-based therapies such as CAR-T cells and gene-corrected stem cells for regenerative medicine. It remains a great challenge, however, to deliver biological effector molecules across the cell membrane with minimal adverse effects on cell viability and functionality. While viral vectors have been frequently used to introduce foreign nucleic acids into cells, their use is associated with safety concerns such as immunogenicity, high manufacturing cost, and limited cargo capacity.For photoporation, depending on the laser energy, membrane permeabilization happens either by local heating or by laser-induced water vapor nanobubbles (VNB). In our first study on this topic, we demonstrated that the physical force exerted by suddenly formed VNB leads to more efficient intracellular delivery as compared to mere heating. Next, we explored the use of different photothermal nanomaterials, finding that graphene quantum dots display enhanced thermal stability compared to the more traditionally used gold nanoparticles, hence providing the possibility to increase the delivery efficiency by repeated laser activation. To enable its use for the production of engineered therapeutic cells, it would be better if contact with cells with nondegradable nanoparticles is avoided as it poses toxicity and regulatory concerns. Therefore, we recently demonstrated that photoporation can be performed with biodegradable polydopamine nanoparticles as well. Alternatively, we demonstrated that nanoparticle contact can be avoided by embedding the photothermal nanoparticles in a substrate made from biocompatible electrospun nanofibers. With this variety of photoporation approaches, over the years we demonstrated the successful delivery of a broad variety of biologics (mRNA, siRNA, Cas9 ribonucleoproteins, nanobodies, etc.) in many different cell types, including hard-to-transfect cells such as T cells, embryonic stem cells, neurons, and macrophages.In this Account, we will first start with a brief introduction of the general concept and a historical development of photoporation. In the next two sections, we will extensively discuss the various types of photothermal nanomaterials which have been used for photoporation. We discriminate two types of photothermal nanomaterials: single nanostructures and composite nanostructures. The first one includes examples such as gold nanoparticles, graphene quantum dots, and polydopamine nanoparticles. The second type includes polymeric films and nanofibers containing photothermal nanoparticles as well as composite nanoscale biolistic nanostructures. A thorough discussion will be given for each type of photothermal nanomaterial, from its synthesis and characterization to its application in photoporation, with its advantages and disadvantages. In the final section, we will provide an overall discussion and elaborate on future perspectives.


Assuntos
Grafite , Nanopartículas Metálicas , Nanoestruturas , Pontos Quânticos , Nanopartículas Metálicas/química , Ouro/química , Grafite/química
2.
J Appl Toxicol ; 44(5): 686-698, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38095138

RESUMO

To evaluate the oral toxicity of nanoparticles (NPs), it is necessary to consider the interactions between NPs and nutrient molecules. Recently, we reported that epigallocatechin gallate (EGCG), a healthy component in green tea, alleviated the toxicity of ZnO NPs to 3D Caco-2 spheroids in vitro. The present study investigated the combined effects of EGCG and ZnO NPs to mice in vivo. Mice were administrated with 35 or 105 mg/kg bodyweight ZnO NPs with or without the presence of 80 mg/kg bodyweight EGCG via gastric route, once a day, for 21 days, and the influences of EGCG on the toxicity of ZnO NPs to intestine were investigated. We found that EGCG altered the colloidal properties of ZnO NPs both in water and artificial intestine juice. As expected, ZnO NPs induced toxicological effects, such as decreased bodyweight, higher Chiu's scores, and ultrastructural changes in intestine, whereas EGCG alleviated these effects. Combined exposure to EGCG and ZnO NPs also changed trace element levels in mouse intestine. For example, the levels of Ti, Co, and Ni were only significantly elevated after co-exposure to EGCG and ZnO NPs, and Fe levels were only significantly decreased by ZnO NPs. Western blot analysis suggested that tight junction (TJ) and endoplasmic reticulum (ER) proteins were elevated by ZnO NPs, but EGCG inhibited this trend. Combined, these data suggested that gastric exposure to ZnO NPs induced intestinal damage, trace element imbalance, and TJ/ER protein expression in mouse intestine, whereas EGCG alleviated these effects of ZnO NPs.


Assuntos
Catequina/análogos & derivados , Nanopartículas , Oligoelementos , Óxido de Zinco , Humanos , Camundongos , Animais , Óxido de Zinco/toxicidade , Óxido de Zinco/química , Células CACO-2 , Nanopartículas/toxicidade , Nanopartículas/química
3.
Environ Toxicol ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856197

RESUMO

Multi-walled carbon nanotubes (MWCNTs) and halloysite nanotubes (HNTs) are widely used tubular-structured nanomaterials (NMs), but their cardiovascular effects are not clear. This study compared the effects of MWCNTs and HNTs on lipid profiles in mouse plasma and gene expression profiles in aortas and hearts. Mice were intravenously injected with 50 µg NMs, once a day, for 5 days. Then, the plasma was collected for lipidomics analysis, and aortas and hearts were collected for RNA-sequencing analysis. While MWCNTs or HNTs did not induce obvious pathological changes in aortas or hearts, the lipid profiles in mouse plasma were altered. Further analysis revealed that MWCNTs more effectively upregulated sphingolipids and sterol lipids, whereas HNTs more effectively upregulated glycerophospholipids and fatty acyls. Consistently, RNA-sequencing data indicated that MWCNTs and HNTs altered signaling pathways related with lipid synthesis and metabolism, as well as those related with endoplasmic reticulum, lysosomes and autophagy, more significantly in aortas than in hearts. We further verified the changes of proteins involved in autophagic lipolysis, that MWCNTs were more effectively to suppress the autophagic biomarker LC3, whereas HNTs were more effectively to affect lipid metabolism proteins. These results may provide novel understanding about the influences of MWCNTs and HNTs on lipid profiles and lipid signaling pathways in cardiovascular systems. Importantly, previous studies considered HNTs as biocompatible materials, but the results from this study suggested that both MWCNTs and HNTs were capable to affect lipid profiles and autophagic lipolysis pathways in cardiovascular systems, although their exact influences were different.

4.
Cell Biol Toxicol ; 39(1): 259-275, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34766255

RESUMO

Although the neurotoxicity of ZnO nanoparticles (NPs) has been evaluated in animal and nerve cell culture models, these models cannot accurately mimic human brains. Three-dimensional (3D) brain organoids based on human-induced pluripotent stem cells have been developed to study the human brains, but this model has rarely been used to evaluate NP neurotoxicity. We used 3D brain organoids that express cortical layer proteins to investigate the mechanisms of ZnO NP-induced neurotoxicity. Cytotoxicity caused by high levels of ZnO NPs (64 µg/mL) correlated with high intracellular Zn ion levels but not superoxide levels. Exposure to a non-cytotoxic concentration of ZnO NPs (16 µg/mL) increased the autophagy-marker proteins LC3B-II/I but decreased p62 accumulation, whereas a cytotoxic concentration of ZnO NPs (64 µg/mL) decreased LC3B-II/I proteins but did not affect p62 accumulation. Fluorescence micro-optical sectioning tomography revealed that 64 µg/mL ZnO NPs led to decreases in LC3B proteins that were more obvious at the outer layers of the organoids, which were directly exposed to the ZnO NPs. In addition to reducing LC3B proteins in the outer layers, ZnO NPs increased the number of micronuclei in the outer layers but not the inner layers (where LC3B proteins were still expressed). Adding the autophagy flux inhibitor bafilomycin A1 to ZnO NPs increased cytotoxicity and intracellular Zn ion levels, but adding the autophagy inducer rapamycin only slightly decreased cellular Zn ion levels. We conclude that high concentrations of ZnO NPs are cytotoxic to 3D brain organoids via defective autophagy and intracellular accumulation of Zn ions.


Assuntos
Nanopartículas Metálicas , Óxido de Zinco , Animais , Humanos , Óxido de Zinco/toxicidade , Zinco , Autofagia , Encéfalo , Organoides/metabolismo , Nanopartículas Metálicas/toxicidade
5.
Macromol Rapid Commun ; 44(4): e2200706, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36353903

RESUMO

Herein novel multicompartment nanoparticles (MCNs) that combine high stability and cargo loading capacity are developed. The MCNs are fabricated by crystallization-driven self-assembly (CDSA) of a tailor-made 21 arm star polymer, poly(L-lactide)[poly(tert-butyl acrylate)-block-poly(ethylene glycol)]20 [PLLA(PtBA-b-PEG)20 ]. Platelet-like or spherical MCNs containing a crystalline PLLA core and hydrophobic PtBA subdomains are formed and stabilized by PEG. Hydrophobic cargos, such as Nile Red and chemotherapeutic drug doxorubicin, can be successfully encapsulated into the collapsed PtBA subdomains with loading capacity two orders of magnitude higher than traditional CDSA nanoparticles. Depolarized fluorescence measurements of the Nile Red loaded MCNs suggest that the free volume of the hydrophobic chains in the nanoparticles may be the key for regulating their drug loading capacity. In vitro study of the MCNs suggests excellent cytocompatibility of the blank nanoparticles as well as a dose-dependent cellular uptake and cytotoxicity of the drug-loaded MCNs.


Assuntos
Nanopartículas , Polímeros , Polímeros/química , Portadores de Fármacos/química , Cristalização , Polietilenoglicóis/química , Nanopartículas/química , Micelas
6.
Langmuir ; 38(50): 15729-15739, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36495271

RESUMO

Membrane separation is of great significance due to its unique performance in treating wastewater. However, the simultaneous treatment of oily emulsions and other complex pollutants in water remains challenging. Herein, we have proposed a simple strategy to prepare a multifunctional titanium dioxide/silver nanoparticles/polyacrylonitrile (TiO2/AgNPs/PAN) nanofibrous membrane. The experimental results showed that the combination of the hierarchical structure composed of PAN nanofibers and Ag/TiO2 nanoprotrusions contributed to the superhydrophilicity and superoleophobicity (UOCA = 153.3 ± 2.0°). Further, the nanofibrous membrane exhibited a rapid gravity-driven permeate flux (>1829.37 ± 83.51 L m-2 h-1) and an ultrahigh separation efficiency (>99.9%) for the surfactant-stabilized oil/water emulsions. Moreover, due to the synergistic effect between the PAN fibers and TiO2/Ag heterojunction, Rhodamine B dye in water can be removed quickly and efficiently (up to 97.67% in 90 min). More importantly, the obtained nanofibrous membrane exhibited ultrahigh stability in different harsh environments. The design of superoleophobic nanofiber membrane with a high separation efficiency and high photocatalytic activity has great potential for practical applications in the purification of oily wastewater.


Assuntos
Nanopartículas Metálicas , Nanofibras , Nanofibras/química , Corantes , Emulsões , Águas Residuárias , Prata , Óleos/química , Bactérias
7.
Biomacromolecules ; 23(9): 3572-3581, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35931466

RESUMO

Inspired by the structure of eukaryotic cells, multicompartmental microcapsules have gained increasing attention. However, challenges remain in the fabrication of "all-aqueous" (i.e., oil-free) microcapsules composed of accurately adjustable hierarchical compartments. This study reports on multicompartmental microcapsules with an innovative architecture. While multicompartmental cores of the microcapsules were fabricated through gas shearing, a shell was applied on the cores through surface gelation of alginate. Different from traditional multicompartmental microcapsules, thus obtained microcapsules have well-segregated compartments while the universal nature of the surface-gelation method allows us to finely tune the shell thicknesses of the microcapsules. The microcapsules are highly stable and cytocompatible and allow repeated enzymatic cascade reactions, which might make them of interest for complex biocatalysis or for mimicking physiological processes.


Assuntos
Alginatos , Água , Alginatos/química , Cápsulas/química , Emulsões/química
8.
Bioorg Chem ; 124: 105792, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35462233

RESUMO

Herein, a high-performance fluorescence probe, namely H4, based on intramolecular charge transfer (ICT) mechanism was developed. H4 could serve as fluorescent probe for detection acidic pH change in environment with outstanding sensitivity, short response time (<10 s), low hemolysis effect (<0.3%) and excellent photostability (>120 min). H4 exhibits a good linear relationship (R2 = 0.9901, Y = 22.0409X-58.3397) characteristics in range of pH 2.2-7.4 with pKa 4.3. In addition, the probe can be also made as fluorescent test sheets and further used as a portable sensor to enhance the screening speed to achieve detection of H+ in real-time. Further, H4 determined H+ in real food samples (milk, shrimps, and scallops) has excellent recoveries (98-105%), which making it of great potential use in food freshness evaluation. Initially, its favorable behavior for detecting H+ change is successfully illustrated in living onion tissues and zebrafish, which allows qualitative visualization of acid pH changes in in biological systems.


Assuntos
Colorimetria , Corantes Fluorescentes , Animais , Corantes Fluorescentes/química , Concentração de Íons de Hidrogênio , Indóis , Peixe-Zebra
9.
Chem Soc Rev ; 50(9): 5746-5776, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33972972

RESUMO

Stimuli-responsive nanobubbles have received increased attention for their application in spatial and temporal resolution of diagnostic techniques and therapies, particularly in multiple imaging methods, and they thus have significant potential for applications in the field of biomedicine. This review presents an overview of the recent advances in the development of stimuli-responsive nanobubbles and their novel applications. Properties of both internal- and external-stimuli responsive nanobubbles are highlighted and discussed considering the potential features required for biomedical applications. Furthermore, the methods used for synthesis and characterization of nanobubbles are outlined. Finally, novel biomedical applications are proposed alongside the advantages and shortcomings inherent to stimuli-responsive nanobubbles.


Assuntos
Pesquisa Biomédica , Nanoestruturas/química , Tamanho da Partícula , Propriedades de Superfície
10.
Bioorg Chem ; 114: 105103, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34174630

RESUMO

Fluorescence probe combines with fluorescence imaging technology has become the most powerful analytical method with their great advantages of high sensitivity and selectivity and real-time monitoring. Ni2+ is widely distributed in food, environment and living animals, thereof, it is of great significance for detection Ni2+ with high selectivity. Herein, a simple strategy is proposed to design and synthesiz a small molecule fluorescent probe Y1 by using "one-pot" method. The spectroscopic behaviors including UV-Vis absorption and fluorescence emission spectrum have been used to verify the feasibility of probe towards Ni2+ in water/EtOH (v/v = 2:8) mixtures under neutral condition. As expected, Y1 offers high selectivity and sensitivity for detection Ni2+ in aqueous solution with a good linear relationship and low detection limit within Ni2+ concentration variation from 0 to 13 µM (DOL = 0.0038 µM, R2 = 0.9983). It is remarkable that Y1 can be applied for real-time visualization Ni2+ change in sprouted potato and zebrafish with great photo-stability, highlighting that the practicability and feasibility of Y1 to detect and monitor Ni2+ in the field of food industry and biomedical field.


Assuntos
Colorimetria , Corantes Fluorescentes/química , Níquel/análise , Solanum tuberosum/química , Animais , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Raios Ultravioleta , Peixe-Zebra
11.
Small ; 16(24): e1907586, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32390312

RESUMO

Barcodes have attracted widespread attention, especially for the multiplexed bioassays and anti-counterfeiting used toward medical and biomedical applications. An enabling gas-shearing approach is presented for generating 10-faced microspherical barcodes with precise control over the properties of each compartment. As such, the color of each compartment could be programmatically adjusted in the 10-faced memomicrospheres by using pregel solutions containing different combinations of fluorescent nanoparticles. During the process, three primary colors (red, green, and blue) are adopted to obtain up to seven merged fluorescent colors for constituting a large amount of coding as well as a magnetic compartment, capable of effective and robust high-throughput information-storage. More importantly, by using the biocompatible sodium alginate to construct the multicolor microspherical barcodes, the proposed technology is likely to advance the fields of food and pharmaceutics anti-counterfeiting. These remarkable properties point to the potential value of gas-shearing in engineering microspherical barcodes for biomedical applications in the future.


Assuntos
Nanopartículas , Bioensaio , Corantes
12.
Ecotoxicol Environ Saf ; 199: 110714, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32446100

RESUMO

Previous studies focused on biocompatibility of graphene oxide (GO) to macrophages, but the impact of GO on lipid profiles in macrophages was less investigated. Herein, we investigated the interactions between THP-1 macrophages and GO of different sizes (GO of size 500-5000 nm, denoted as GO-L; GO of size < 500 nm, denoted as GO-S). We found that after 24 h exposure, the internalization of GO appeared to be minimal, whereas up to 50 µg/mL of GO-L but not GO-S reduced lipid accumulation, accompanying with a significantly reduced release of soluble monocyte chemoattractant protein-1 (MCP-1) but not interleukin-6 (IL-6). Moreover, lipidomic data showed that GO-L decreased the levels of 17 lipid classes, whereas GO-S only decreased the levels of 5 lipid classes. For comparison, 50 µg/mL carbon black (CB) significantly increased lipid accumulation with considerable particle internalization. GO-reduced lipid accumulation was not related with increase of reactive oxygen species (ROS) or induction of autophagy, and modulation of autophagy by chemicals showed no significant effect to alter the effects of GO-L on lipid accumulation. However, exposure to GO reduced the mRNA and protein levels of key components in peroxisome proliferators-activated receptor (PPAR) signaling pathway, a pathway that is related with lipid droplet biogenesis, and the modulation of PPARγ by chemicals altered the effects of GO-L on lipid accumulation. In conclusion, our results suggested that GO size-dependently altered lipid profiles in THP-1 macrophages that might be related with PPAR signaling pathway.


Assuntos
Grafite/química , Grafite/toxicidade , Metabolismo dos Lipídeos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimiocina CCL2/metabolismo , Humanos , Macrófagos/metabolismo , Macrófagos/patologia , PPAR gama/metabolismo , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Células THP-1
13.
Nanotechnology ; 30(4): 045602, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30479314

RESUMO

Recently, there has been strong interest in flexible and wearable electronics to meet the technological demands of modern society. Environmentally-friendly and scalable electronic textiles is a key area that is still significantly underdeveloped. Here, we describe a novel strain sensor composed of aligned cellulose acetate (CA) nanofibers with belt-like morphology and a reduced graphene oxide (RGO) layer. The unique spatial alignment, microstructure and wettability of CA nanofibrous membranes facilitate their close contact with deposited GO colloids. After a portable and fast hot-press process within 700 s at 150 °C, the GO on CA membrane can be facilely reduced to a conductive RGO layer. Moreover, the connection among contiguous CA nanofibers and the interaction between the GO and CA substrate were both highly enhanced, resulting in superior mechanical strength with Young's modulus of 1.3 GPa and small sheet resistance lower than 10 kΩ. Therefore, the conductive RGO/CA membrane was successfully utilized as a strain sensor in a broad deformation range and with versatile deformation types. Moreover, the distinctive mechanical strength under different stretch angles endowed the well-aligned RGO/CA film with intriguing sensitivity against stress direction. Such a cost-effective and environmentally-friendly method can be easily extended to the scalable production of graphene-based flexible electronic textiles.

14.
Phys Chem Chem Phys ; 21(37): 21064-21069, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31528951

RESUMO

By performing first principles calculations, we predict a new two-dimensional semiconductor, namely the SnP2S6 monolayer as a potential photocatalyst for solar water splitting. The exfoliation of the SnP2S6 monolayer from the experimentally-known layered bulk crystal is feasible by overcoming a small cleavage energy of 0.24 J m-2. The SnP2S6 monolayer is a stable semiconductor with an indirect band gap of 2.23 eV, which can be effectively tuned by applying an in-plane biaxial strain. In particular, an indirect-to-direct band gap transition can be achieved under compressive strain. The band edge alignments of the monolayer match well with the water redox potentials. The carrier mobility of the SnP2S6 monolayer is as high as 143.12 and 148.48 cm2 V-1 s-1 for holes and electrons, respectively. These extraordinary electronic properties as well as the good light harvesting performance render the SnP2S6 monolayer a good candidate for electronics and a promising photocatalyst to split water.

15.
Biomacromolecules ; 19(12): 4565-4575, 2018 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-30412387

RESUMO

This work investigates multifunctional composite films synthesized with cellulose nanofibers (CNFs) and poly(vinyl alcohol) (PVA). First, TEMPO-oxidized CNFs were modified in the heterogeneous phase with benzophenone, diisocyanate, and epoxidized soybean oil via esterification reactions. A thorough characterization was carried out via elemental analysis as well as FT-IR and X-ray photoelectron spectroscopies and solid-state NMR. Following, the surface-modified CNFs were combined with PVA to endow composite films with UV-absorbing capabilities while increasing their thermomechanical strength and maintaining a high light transmittance. Compared to neat PVF films, the tensile strength, Young modulus, and elongation of the films underwent dramatic increases upon addition of the reinforcing phase (maximum values of ∼96 MPa, ∼ 714 MPa, and ∼350%, respectively). A high UV blocking performance, especially in the UVB region, was observed for the introduced multifunctional PVA films at CNF loadings below 5 wt %. The trade-off between modified nanofibril function as interfacial reinforcement and aggregation leads to an optimum loading. The results indicate promising applications, for example, in active packaging.


Assuntos
Celulose Oxidada/química , Celulose/química , Nanocompostos/química , Nanofibras/química , Polissacarídeos/química , Álcool de Polivinil/química , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração , Raios Ultravioleta
16.
Nanotechnology ; 29(34): 345607, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-29920185

RESUMO

Developing a facile strategy to synthesize template-free TiO2 membrane with stable super-hydrophilic surface is still a daunting challenge. In this work, super-hydrophilicity (close to 0°) and underwater super-oleophobicity (165°) have been successfully demonstrated on a hierarchical Al2O3/TiO2 membrane, which is prepared via a facile electrospinning method followed by simple calcination in air. The precisely-tuned Al2O3 heterojunctions grew in situ and dispersed uniformly on the TiO2 surface, resulting in an 'island in the sea' configuration. Such a unique feature allows not only achieving super-hydrophilicity by maximizing the surface roughness and enhancing the hydrogen bonding, but also improving the adsorption capacity toward different toxic dyes utilizing the abundant adsorption sites protected by the hierarchical nanostructure during sintering. The new Al2O3/TiO2 nanofibrous membrane can serve as a novel filter for gravity driven oil/water separation along with dye removal, achieving 97.7% of oil/water separation efficiency and 98% of dye capture, thanks to their superb wettability and the sophisticated adsorptive performance. Our presented fabrication strategy can be extended to a wide range of ceramic materials and inspires their advanced applications in water purification under harsh liquid-phase environments.

17.
Bioorg Med Chem Lett ; 27(5): 1296-1300, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28169166

RESUMO

A series of new 1H-benzo[d]imidazole derivatives of dehydroabietic acid were designed and synthesized as potent antitumor agents. Structures of the target molecules were characterized using MS, IR, 1H NMR, 13C NMR and elemental analyses. In the in vitro cytotoxic assay, most compounds showed significant cytotoxic activities against two hepatocarcinoma cells (SMMC-7721 and HepG2) and reduced cytotoxicity against noncancerous human hepatocyte (LO2). Among them, compound 7b exhibited the best cytotoxicity against SMMC-7721 cells (IC50: 0.36±0.13µM), while 7e was most potent to HepG2 cells (IC50: 0.12±0.03µM). The cell cycle analysis indicated that compound 7b caused cell cycle arrest of SMMC-7721 cells at G2/M phase. Further, compound 7b also induced the apoptosis of SMMC-7721 cells in Annexin V-APC/7-AAD binding assay.


Assuntos
Abietanos/química , Antineoplásicos/síntese química , Imidazóis/síntese química , Imidazóis/toxicidade , Antineoplásicos/toxicidade , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Imidazóis/química , Concentração Inibidora 50 , Estrutura Molecular
18.
Nanotechnology ; 27(39): 395707, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27574002

RESUMO

Regenerated cellulose (RC)-based composites reinforced with multi-walled carbon nanotubes (MWCNTs) were prepared by a facile casting method. The morphology and microstructure of the fabricated composites were characterized using transmission electron microscopy, Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. Thermogravimetry and derivative thermogravimetric analysis were conducted to investigate the effect of MWCNTs on the thermal behaviors of the RC. The results showed that the introduction of MWCNTs enhanced the thermal stability of the RC. Moreover, the effect of the dispersion state of MWCNTs in microcrystalline cellulose/ZnCl2 solutions with varying MWCNT loadings was studied by rheological tests. The mechanical properties of composite films were remarkably improved compared to those of pure RC film. Specifically, the composite film containing 3 wt% of MWCNTs exhibits a 123% enhancement in tensile strength and a 163% enhancement in the Young's modulus compared with the pure RC film.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38615809

RESUMO

Graphdiyne (GDY) is a new member of family of carbon-based 2D nanomaterials (NMs), but the environmental toxicity is less investigated compared with other 2D NMs, such as graphene oxide (GO). In this study, we compared with developmental toxicity of GO and GDY to zebrafish larvae. It was shown that exposure of zebrafish embryos from 5 h post fertilization to GO and GDY for up to 5 days decreased hatching rate and induced morphological deformity. Behavioral tests indicated that GO and GDY treatment led to hyperactivity of larvae. However, blood flow velocity was not significantly affected by GO or GDY. RNA-sequencing data revealed that both types of NMs altered gene expression profiles as well as gene ontology terms and KEGG pathways related with metabolism. We further confirmed that the NMs altered the expression of genes related with lipid droplets and autophagy, which may be account for the delayed development of zebrafish larvae. At the same mass concentrations, GO induced comparable or even larger toxic effects compared with GDY, indicating that GDY might be more biocompatible compared with GO. These results may provide novel understanding about the environmental toxicity of GO and GDY in vivo.


Assuntos
Grafite , Larva , Peixe-Zebra , Animais , Grafite/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Embrião não Mamífero/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos
20.
Int J Biol Macromol ; 254(Pt 1): 127707, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37923046

RESUMO

The pollution of heavy metals such as Cu2+ is still serious and the discharge of sewage of Cu2+ will cause damage to soil environment and human health. Herein, a biomass-based solid-state fluorescence detection platform (CPU-CDs) was developed as fluorescent sensor for detection Cu2+ via fluorescence and colorimetric dual-model methods in real time. CPU-CDs was composed of xylan-derived CDs (U-CDs) and cotton cellulose paper, which exhibiting good reusability, non-toxicity, excellent fluorescence characteristics and high biocompatibility. Further, CPU-CDs displayed high effectiveness and sensitivity for Cu2+ with the detection limit as low as 0.14 µM, which was well below U.S. EPA safety levels (20 µM). Practical application indicated that CPU-CDs could achieve precision response of Cu2+ change in real environment water samples with good recovery range of 90 %-119 %. This strategy demonstrated a promising biomass solid-state fluorescence sensor for Cu2+ detection for water treatment research, which is of great significance in dealing with water pollution caused by heavy metal ions.


Assuntos
Pontos Quânticos , Humanos , Espectrometria de Fluorescência/métodos , Limite de Detecção , Xilanos , Celulose , Carbono , Corantes Fluorescentes
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