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1.
J Photochem Photobiol B ; 202: 111716, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31821944

RESUMO

Though anesthetic drug delivery system and drug vehicles is generally applied for pain relief, there are have many difficulties and issues due to its short duration carrier and low biocompatibility, effectiveness at the conditions of inflammation at acidic pH. To resolve this issue, we have designed and developed the dual (pH and temperature) responsive bio-nanomaterial to improve the efficiency anesthetic drug delivery system. Chitosan is a unique class of biomaterials that is widely used in medical devices. The surface engineering of ZnFe2O4 nanoparticles was performed by coating with chitosan using simple precipitation method. Then, multi-active anesthetic drug (Lidocaine) was loaded into nano-ferrite to form a drug delivery vehicle. The prepared drug-vesicle was characterized by using XRD, FTIR, SEM, XPS and TGA analysis. XRD analysis proved the face center cubic structure of zinc nanoferrite. The sustained delivery of Lidocaine (LDC) from CS coated nanoferrite (CS/ZnFe2O4) was stimulated by pH and temperature responsive characteristics of vesicles. The in vitro cytotoxicity of the CS/ZnFe2O4 particles towards fibroblast cells was analyzed by using MTT assay. The drug loaded CS/ZnFe2O4 particles exhibit high biocompatibility and sustained drug release in the physiological pH environment (4.8, 5.5 and 7.4) and temperature responsive (25 and 37 °C) of normal tissues and also drug loading efficiency was measured.


Assuntos
Anestésicos/química , Quitosana/química , Portadores de Fármacos/química , Nanoestruturas/química , Anestésicos/metabolismo , Anestésicos/uso terapêutico , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Lidocaína/química , Lidocaína/metabolismo , Magnetismo , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/toxicidade , Nanoestruturas/toxicidade , Dor/tratamento farmacológico , Ratos , Temperatura Ambiente
2.
Food Chem ; 305: 125475, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518841

RESUMO

Pea protein-stabilized nanoemulsions were prepared to encapsulate vitamin D with the aim to develop novel non-dairy functional foods for vitamin D fortifications. Homogenization conditions of 20 kpsi and two homogenization cycles were identified as optimal conditions for producing stable nanoemulsions. The nanoemulsions exhibited controllable sizes (170-350 nm), good stability with zeta-potential of -25 mV, and high vitamin encapsulation efficiency (94-96%). Cellular uptake efficiency of small sized nanoemulsions (233 nm) was ~2.5 times higher than large sized nanoemulsions (350 nm). Interestingly, protein-based nanoemulsions exhibited significantly higher cellular uptake than emulsions prepared using a combination of protein and lecithin. The vitamin D transport efficiency across Caco-2 cells for small sized nanoemulsions (233 nm) was ~5.3 times greater than free vitamin D suspension. This research demonstrated that pea protein can be used as an effective emulsifier for preparing food nanoemulsions, which may enhance vitamin D bioavailability and improve vitamin deficiency status in aged population.


Assuntos
Emulsões/química , Nanoestruturas/química , Proteínas de Ervilha/química , Vitamina D/química , Células CACO-2 , Sobrevivência Celular , Emulsificantes/química , Humanos , Lecitinas/química , Nanoestruturas/toxicidade , Tamanho da Partícula , Pressão , Estabilidade Proteica , Vitamina D/metabolismo
3.
J Photochem Photobiol B ; 201: 111683, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31710928

RESUMO

In recent years dendrimers have fascinated the investigators towards targeted drug delivery because of their versatile framework and exhibit immense potentiality in entrapping drug moieties through host-guest interactions and serve as a promising vector in biological applications. The current investigation is focused on developing pegylated citric acid cefotaxime dendrimers through the divergent method and its characterization through spectroscopic, microscopic, thermal and microscopic techniques. Among the spectroscopic techniques, 1H NMR and 13C NMR elucidated the key functional groups at various chemical shifts while ESI-MS pointed out the molecular weight of cefotaxime sodium in various generations. Similarly, FTIR, DSC, and AFM investigations detailed that the generations are devoid of incompatibilities, structural deformities and can be opted for targeted drug delivery. The drug entrapment studies and in-vitro drug release studies highlight CFTX G5 containing 92.4% entrapment efficacy and 83.8% drug release in 48 h and specifies a sustain release characteristics. In connection to the above, the in-vivo studies reveal a potent antibacterial activity against various gram-positive and gram-negative microorganisms with a decreased hemolysis and cytotoxicity effects and reflect a high margin of safety regarding pegylated CFTX dendrimers. Further, the antibacterial activities are supported through confocal microscopy that clarified the cellular uptake of dendritic molecules and their internalization.


Assuntos
Cefotaxima/química , Ácido Cítrico/química , Dendrímeros/química , Nanoestruturas/química , Células A549 , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Cefotaxima/metabolismo , Cefotaxima/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Meia-Vida , Hemólise/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Nanoestruturas/toxicidade , Polietilenoglicóis/química
4.
Ecotoxicol Environ Saf ; 186: 109810, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31629190

RESUMO

Little is known about how the chemical properties (molecular structure, such as the hydrophobic and hydrophilic end group for organic chemical, and particle size for nanomaterials (NMs)) quantitatively affect the toxicokinetics (TK) in organisms especially in short-term, single-species studies. A novel method based on a first-order one compartment TK model which described the monophasic uptake pattern and two-compartment TK model which adequately described the biphasic metabolism pattern was used to determine the bioconcentration and TK rate constants of organic compounds (n = 17) and nanomaterials (NMs, n = 7) in zebrafish. For both one and two compartment model, the uptake (kin) and elimination (kout) rate constants were fitted using a one- and two-compartment first-order kinetic model, and bioconcentration factors (BCF) and 95% depuration times (t95) for all tested chemicals were calculated, respectively. The results showed that there was significant difference in TK parameters kin, kout, and BCF between organic chemicals and nano metal oxides. For organic compounds, significant correlations were found between the kin and BCF and the octanol-water partition coefficient (Kow) and molecular mass. For nano metal oxides, there was a significant negative correlation between the kin or BCF and particle size, but a positive correlation between kin and Zeta potential of nanoparticles and also a significant positive correlation between kout and particle size or specific surface area. Those findings indicated that NMs particle size does matter in biological influx and efflux processes. Our results suggest that the TK process for organic compound and NMs are correlated by different chemical properties and highlight that the Kow, the absorption kin, metabolism k12 and k21, elimination rate kout, and all the parameters that enable the prediction and partitioning of chemicals need to be precisely determined in order to allow an effective TK modeling. It would therefore appear that the TK process of untested chemicals by a fish may be extrapolated from known chemical properties.


Assuntos
Nanoestruturas/química , Compostos Orgânicos/química , Compostos Orgânicos/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Modelos Teóricos , Nanoestruturas/toxicidade , Compostos Orgânicos/metabolismo , Toxicocinética , Poluentes Químicos da Água/metabolismo
5.
Aquat Toxicol ; 216: 105297, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31550666

RESUMO

Since its discovery in 2004, graphene has been used in a wide variety of fields including biomedicine, electronics, filtration materials, and surface coatings. The rapidly expanding consumer market for graphene family nanomaterials (GFNs), such as graphene oxide (GO), raises concern regarding their environmental toxicity. The aim of this study was to evaluate the effects of GO exposures in a marine filter-feeding bivalve (Crassostrea virginica) using sublethal biomarker approaches that can contribute to the development of an adverse outcome pathway (AOP). A 14-day study was conducted to identify tissue-specific molecular markers of GO toxicity using a static renewal design. Elevated lipid peroxidation and changes in glutathione-s-transferase (GST) activities were observed in gills and digestive gland tissues of the GO-exposed oysters. These cellular changes were noted for 2.5 and 5 mg/L GO exposures in seawater. Based on our results, reactive oxygen species (ROS)-induced oxidative damage is identified as a key event in the proposed AOP. Additionally, detoxification enzymes, such as GST, are thought to be involved in stress signaling leading to adverse effects on cellular health. This study is a part of our two-tier approach towards the identification of short- and long-term effects of GO exposures. This work, together with our previous 72 h exposure, represents the application of biomarker-based investigations in the process of AOP development for graphene family nanomaterials.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Crassostrea/efeitos dos fármacos , Exposição Ambiental , Grafite/toxicidade , Nanoestruturas/toxicidade , Animais , Biomarcadores/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Tamanho da Partícula , Proteínas/metabolismo , Poluentes Químicos da Água/toxicidade
6.
Int J Nanomedicine ; 14: 6539-6553, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496699

RESUMO

Aim: This paper reports on the incorporation of oleic acid (OA) within nanostructured lipid carriers (OA-NLC) to improve the anti-inflammatory effects in the presence of albumin. Materials and methods: NLCs produced via hot high-shear homogenization/ultrasonication were characterized in terms of particle size, zeta potential, and toxicity. We examined the effects of OA-NLC on neutrophil activities. Dermatologic therapeutic potential was also elucidated by using a murine model of leukotriene B4-induced skin inflammation. Results: In the presence of albumin, OA-NLC but not free OA inhibited superoxide generation and elastase release. Topical administration of OA-NLC alleviated neutrophil infiltration and severity of skin inflammation. Conclusion: OA incorporated within NLC can overcome the interference of albumin, which would undermine the anti-inflammatory effects of OA. OA-NLC has potential therapeutic effects in topical ointments.


Assuntos
Portadores de Fármacos/química , Inflamação/patologia , Lipídeos/química , Nanoestruturas/química , Neutrófilos/fisiologia , Ácido Oleico/química , Soroalbumina Bovina/farmacologia , Pele/patologia , Administração Tópica , Adulto , Animais , Cálcio/metabolismo , Bovinos , Morte Celular/efeitos dos fármacos , Portadores de Fármacos/administração & dosagem , Humanos , Leucotrieno B4 , Lipídeos/toxicidade , Masculino , Camundongos Endogâmicos BALB C , Nanoestruturas/administração & dosagem , Nanoestruturas/toxicidade , Nanoestruturas/ultraestrutura , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Ácido Oleico/toxicidade , Elastase Pancreática/metabolismo , Superóxidos/metabolismo , Adulto Jovem
7.
Ecotoxicol Environ Saf ; 184: 109602, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31493589

RESUMO

Given the wide applications of engineered nanomaterials (ENMs) in various fields, the ecotoxicology of ENMs has attracted much attention. The traditional plant physiological activity (e.g., reactive oxygen species and antioxidant enzymes) are limited in that they probe one specific process of nanotoxicity, which may result in the loss of understanding of other important biological reactions. Metabolites, which are downstream of gene and protein expression, are directly related to biological phenomena. Metabolomics is an easily performed and efficient tool for solving the aforementioned problems because it involves the comprehensive exploration of metabolic profiles. To understand the roles of metabolomics in phytotoxicity, the analytical methods for metabolomics should be organized and discussed. Moreover, the dominant metabolites and metabolic pathways are similar in different plants, which determines the universal applicability of metabolomics analysis. The analysis of regulated metabolism will globally and scientifically help determine the ecotoxicology that is induced by ENMs. In the past several years, great developments in nanotoxicology have been achieved using metabolomics. However, many knowledge gaps remain, such as the relationships between biological responses that are induced by ENMs and the regulation of metabolism (e.g., carbohydrate, energy, amino acid, lipid and secondary metabolism). The phytotoxicity that is induced by ENMs has been explored by metabolomics, which is still in its infancy. The detrimental and defence mechanisms of plants in their response to ENMs at the level of metabolomics also deserve much attention. In addition, owing to the regulation of metabolism in plants by ENMs affected by multiple factors, it is meaningful to uniformly identify the key influencing factor.


Assuntos
Metaboloma/efeitos dos fármacos , Nanoestruturas/toxicidade , Plantas/efeitos dos fármacos , Plantas/metabolismo , Antioxidantes/metabolismo , Ecotoxicologia , Redes e Vias Metabólicas/efeitos dos fármacos , Metabolômica , Nanoestruturas/química , Espécies Reativas de Oxigênio/metabolismo
8.
Sci Total Environ ; 694: 133717, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400676

RESUMO

Biofouling causes massive economical losses in the maritime sector creating an urgent need for effective and ecologically non-harmful antifouling materials. Zinc oxide (ZnO) nanorod coatings show promise as an antifouling material; however, the toxicity of ZnO nanorods to marine organisms is not known. We compared the toxicity of suspended ZnO nanorods (NR) with that of ZnO nanoparticles (NP) and ionic Zn2+ in a marine bivalve Mytilus edulis exposed for two weeks to 10 or 100 µg Zn L-1 of ZnO NPs, NRs or Zn2+, or to immobilized NRs. The multi-biomarker assessment included bioenergetics markers (tissue energy reserves, activity of mitochondrial electron transport system and autophagic enzymes), expression of apoptotic and inflammatory genes, and general stress biomarkers (oxidative lesions, lysosomal membrane stability and metallothionein expression). Exposure to ZnO NPs, NRs and Zn2+ caused accumulation of oxidative lesions in proteins and lipids, stimulated autophagy, and led to lysosomal membrane destabilization indicating toxicity. However, these responses were not specific for the form of Zn (NPs, NR or Zn2+) and showed no monotonous increase with increasing Zn concentrations in the experimental exposures. No major disturbance of the energy status was found in the mussels exposed to ZnO NPs, NRs, or Zn2+. Exposure to ZnO NPs and NRs led to a strong induction of apoptosis- and inflammation-related genes, which was not seen in Zn2+ exposures. Based on the integrated biomarker response, the overall toxicity as well as the pro-apoptotic and pro-inflammatory action was stronger in ZnO NPs compared with the NRs. Given the stability of ZnO NR coatings and the relatively low toxicity of suspended ZnO NR, ZnO NR coating might be considered a promising low-toxicity material for antifouling paints.


Assuntos
Mytilus edulis/fisiologia , Nanoestruturas/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Animais , Biomarcadores/metabolismo , Metabolismo Energético , Estresse Fisiológico
9.
Nanoscale ; 11(32): 15326-15338, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31386732

RESUMO

All-in-one nanoagents with a single-component and all-required functions have attracted increasing attention for the imaging-guided therapy of tumors, but the design and preparation of such nanoagents remain a challenge. Herein, we report the introduction of oxygen vacancies to traditional semiconductors with heavy-metal elements for tuning photoabsorption in the near infrared (NIR) region, by using Bi2WO6 (band-gap: ∼2.7 eV) as a model. Bi2WO6-x nanodots with sizes of ∼3 or ∼8 nm have been prepared by a facile coprecipitation-solvothermal method assisted by citric acid (CA, 0.1-1.5 g) as the reduction agent. CA confers the removal of O atoms from the [Bi2O2]2+ layer during the solvothermal process, resulting in the formation of plenty of oxygen vacancies in the Bi2WO6-x crystal. As a result, NIR photoabsorption of Bi2WO6-x nanodots can be remarkably enhanced with the increase of the CA amount from 0 to 1.0 g. Under irradiation of a single-wavelength (808 nm, 1.0 W cm-2) NIR laser, black Bi2WO6-x-CA1.0 nanodots can not only efficiently produce a sufficient amount of heat with a photothermal conversion efficiency of 45.1% for photothermal therapy, but also generate singlet oxygen (1O2) for photodynamic therapy. Furthermore, due to the presence of heavy-metal (Bi and W) elements, Bi2WO6-x-CA1.0 nanodots have high X-ray attenuation ability for CT imaging. After the Bi2WO6-x-CA1.0 nanodot dispersion is injected into the tumor-bearing mice, the tumor can be imaged by using CT and an IR thermal camera. After irradiation with a single-wavelength (808 nm, 1.0 W cm-2, 10 min) NIR laser, the tumor can be completely suppressed by the synergic photothermal and photodynamic effects of Bi2WO6-x-CA1.0 nanodots, without recurrence and treatment-induced toxicity. Therefore, Bi2WO6-x nanodots have great potential as a novel all-in-one nanoagent for the imaging and phototherapy of tumors.


Assuntos
Bismuto/química , Nanoestruturas/química , Oxigênio/química , Compostos de Tungstênio/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Raios Infravermelhos , Iohexol/análogos & derivados , Iohexol/química , Iohexol/farmacologia , Camundongos , Nanoestruturas/uso terapêutico , Nanoestruturas/toxicidade , Neoplasias/diagnóstico , Neoplasias/patologia , Neoplasias/terapia , Fotoquimioterapia , Fototerapia , Oxigênio Singlete/química , Oxigênio Singlete/metabolismo , Temperatura Ambiente , Distribuição Tecidual , Tomografia Computadorizada por Raios X
10.
Environ Pollut ; 254(Pt A): 112978, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31398636

RESUMO

Although amino modified nanopolystyrene could cause toxicity on environmental organisms, the effect of amino modification on nanopolystyrene toxicity is still largely unclear. We here employed Caenorhabditis elegans as an animal model to compare the effects between pristine and amino modified nanopolystyrene particles in inducing reproductive toxicity. Nanopolystyrene (35 nm) could cause the damage on gonad development as indicated by the endpoints of number of total germline cells, length of gonad arm, and relative area of gonad arm. Nanopolystyrene exposure also reduced the reproductive capacity as reflected by the endpoints of brood size and number of fertilized eggs in uterus. Moreover, amino modification enhanced nanopolystyrene toxicity on both the gonad development and the reproductive capacity. Additionally, induction of germline apoptosis and formation of germline DNA damage contributed to the enhancement of nanopolystyrene toxicity in reducing reproductive capacity by amino modification. Our results highlight the potential environmental risk of amino modified nanopolystyrene in inducing reproductive toxicity on gonad development and reproductive capacity of environmental organisms.


Assuntos
Caenorhabditis elegans/embriologia , Dano ao DNA/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Gônadas/embriologia , Poliestirenos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Feminino , Modelos Animais , Nanoestruturas/toxicidade , Reprodução/efeitos dos fármacos
11.
Carbohydr Polym ; 223: 115061, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426963

RESUMO

In this study, chitosan oligosaccharide (COS)-vanillin imine (COS-Vani Imine)-based dual pH responsive nano-micelles (DPRNs) were synthesized. The resultant DPRNs were used for encapsulating genistein and its ultimate release upon pH change. The overall concept of DPRNs for the targeted delivery of hydrophobic anticancer drugs was successfully demonstrated. The DPRNs were spherical in shape, nanoscale in dimension (71.2-163.4 nm), with dual pH response. The encapsulation/loading of genistein into DPRNs was achieved and the resultant genistein-loaded DPRNs were stable under the physiological pH (˜7.4); under the cancer cell extracellular pH (˜6.8), the amino groups in COS is protonated, thus becoming positively charged, facilitating their adsorption onto negatively charged cancer cells. Under the cancer cell intracellular pH (˜5.0), the genistein-loaded DPRNs were destroyed as a result of the cleavage of pH sensitive benzoic imine, thereby releasing the loaded genistein.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Micelas , Nanoestruturas/química , Oligossacarídeos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Quitosana/síntese química , Quitosana/toxicidade , Portadores de Fármacos/síntese química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Genisteína/química , Genisteína/farmacologia , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Nanoestruturas/toxicidade , Oligossacarídeos/síntese química , Oligossacarídeos/toxicidade
12.
J Food Sci ; 84(9): 2572-2583, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31436862

RESUMO

This study was aimed to develop a novel nanocarrier for coenzyme Q10 (CoQ10) by a green process that prevented the use of surfactants and organic solvents. Triglyceride/phospholipid-based nanocarriers were developed through high-pressure homogenization (an industrial feasible process), and a 25-1 fractional factorial design was adopted to assess the influences of formulation variables on the considered responses, including vesicle size, entrapment efficiency, loading capacity, and solubility of the vehicles in simulated gastrointestinal fluids. The optimized formulation was further in-depth characterized in terms of morphology, release behavior, biocompatibility (Caco-2 cell cytotoxicity and histological examination), thermal behavior, and Fourier transform infrared analysis. Optimal nanocarriers were found to have mean particle size of 75 nm, narrow particle distribution, and CoQ10 entrapment of 95%. The optimized formulation was stable upon incubation in simulated gastrointestinal fluids without considerable leakage of cargo, which was in agreement with their sustained release behavior. Microscopic observations also confirmed nanosized nature of the vesicles and revealed their spherical shape. Moreover, toxicity evaluations at the cellular and tissue levels revealed their nontoxic nature. In conclusion, triglyceride/phospholipid-based nanocarriers proved to be a green safe vehicle for delivery of CoQ10 with industrial-scale production capability and could provide a new horizon for delivery of hydrophobic nutraceuticals. PRACTICAL APPLICATION: Green nanostructure formulation approaches have recently gained tremendous attraction for their safe profile especially when it comes to supplements, which are generally recommended for daily use. However, their sufficient association with cargoes and industrial-scale production have remained considerable challenges. This study focuses on the development of lipid-based nanocarriers for CoQ10 by an industrial feasible process that prevents the use of any surfactants or organic solvents.


Assuntos
Portadores de Fármacos , Nanoestruturas , Fosfolipídeos , Triglicerídeos , Ubiquinona/análogos & derivados , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Química Verde , Humanos , Nanoestruturas/química , Nanoestruturas/toxicidade , Fosfolipídeos/química , Fosfolipídeos/toxicidade , Triglicerídeos/química , Triglicerídeos/toxicidade , Ubiquinona/química , Ubiquinona/farmacocinética
13.
Ecotoxicol Environ Saf ; 183: 109568, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31437729

RESUMO

We employed nematode Caenorhabditis elegans to determine the combinational effect between nanopolystyrene at predicted environmental concentration and microcystin-LR (MC-LR). Prolonged exposure to nanopolystyrene (1 µg/L) increased MC-LR (0.1 µg/L) toxicity in reducing brood size and locomotion behavior and in inducing oxidative stress. Moreover, the adsorption of MC-LR by nanopolystyrene particles played an important role in inducing the enhancement in MC-LR toxicity by nanopolystyrene particles. Additionally, only exposure to resuspension of nanopolystyrene (1 µg/L) caused the increased intestinal permeability in MC-LR (0.1 µg/L) exposed nematodes. Our data indicates the potential of nanopolystyrene at predicted environmental concentration in enhancing MC-LR toxicity on environmental organisms.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Intestinos/efeitos dos fármacos , Microcistinas/toxicidade , Nanoestruturas/toxicidade , Poliestirenos/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Relação Dose-Resposta a Droga , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Locomoção/efeitos dos fármacos , Microcistinas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Permeabilidade
14.
Biosens Bioelectron ; 142: 111573, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31412314

RESUMO

Layered transition metal dichalcogenides (TMDs) are important members in the family of two-dimensional (2D) materials. The large surface-to-volume ratio, combined with the fascinating tunable electronic and optical properties, low toxicity, unique van der Waals layered structure, and engineerable surface structure, renders 2D TMDs highly valuable for next-generation biosensing applications. Herein, the recent progress in the development of 2D TMDs-based biosensors is comprehensively reviewed, with special focus on the implementation of the structural, electronic and optical properties of 2D TMDs in the realization of high-performance biosensors with different configurations for a wide spectrum of bioanalytes and bio-species. In addition, the comparison on biosensing performances with graphene as the currently most studied 2D candidate is critically discussed. Finally, future perspectives are provided along the development progress of 2D TMDs-based biosensors which are currently undergoing an intense study. This work will lead researchers to explore more novel sensing candidates within the category of TMDs with exotic chemical composition, structure, morphologies, dimensionalities, and properties.


Assuntos
Técnicas Biossensoriais/métodos , Metais/química , Nanoestruturas/química , Animais , Técnicas Biossensoriais/instrumentação , Desenho de Equipamento , Grafite/química , Grafite/toxicidade , Humanos , Metais/toxicidade , Nanoestruturas/toxicidade , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Elementos de Transição/química , Elementos de Transição/toxicidade
15.
Nanoscale ; 11(28): 13458-13468, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31287475

RESUMO

The large number of nanomaterial-based applications emerging in the materials and life sciences and the foreseeable increasing use of these materials require methods that evaluate and characterize the toxic potential of these nanomaterials to keep safety risks to people and environment as low as possible. As nanomaterial toxicity is influenced by a variety of parameters like size, shape, chemical composition, and surface chemistry, high throughput screening (HTS) platforms are recommended for assessing cytotoxicity. Such platforms are not yet available for genotoxicity testing. Here, we present first results obtained for application-relevant nanomaterials using an automatable genotoxicity platform that relies on the quantification of the phosphorylated histone H2AX (γ-H2AX) for detecting DNA double strand breaks (DSBs) and the automated microscope system AKLIDES® for measuring integral fluorescence intensities at different excitation wavelengths. This platform is used to test the genotoxic potential of 30 nm-sized citrate-stabilized gold nanoparticles (Au-NPs) as well as micellar encapsulated iron oxide nanoparticles (FeOx-NPs) and different cadmium (Cd)-based semiconductor quantum dots (QDs), thereby also searching for positive and negative controls as reference materials. In addition, the influence of the QD shell composition on the genotoxic potential of these Cd-based QDs was studied, using CdSe cores as well as CdSe/CdS core/shell and CdSe/CdS/ZnS core/shell/shell QDs. Our results clearly revealed the genotoxicity of the Au-NPs and its absence in the FeOx-NPs. The genotoxicity of the Cd-QDs correlates with the shielding of their Cd-containing core, with the core/shell/shell architecture preventing genotoxicity risks. The fact that none of these nanomaterials showed cytotoxicity at the chosen particle concentrations in a conventional cell viability assay underlines the importance of genotoxicity studies to assess the hazardous potential of nanomaterials.


Assuntos
Cádmio/química , Histonas/metabolismo , Testes de Mutagenicidade/métodos , Nanoestruturas/toxicidade , Pontos Quânticos/química , Cádmio/toxicidade , Sobrevivência Celular , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Compostos Férricos/química , Compostos Férricos/toxicidade , Fluorometria , Ouro/química , Ouro/toxicidade , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Testes de Mutagenicidade/instrumentação , Nanoestruturas/química , Tamanho da Partícula , Fosforilação/efeitos dos fármacos , Pontos Quânticos/toxicidade
16.
Int J Pharm ; 569: 118484, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31260785

RESUMO

Re-activation of the healing process is a major challenge in the field of chronic wound treatment. For that purpose, lipid-nanoparticles, especially nanostructured lipid carriers (NLC), possess extremely useful characteristics such as biodegradability, biocompatibility and long-term stability, besides being suitable for drug delivery. Moreover, they maintain wound moisture due to their occlusive properties, which have been associated with increased healing rates. In the light of above, NLC have been extensively used topically for wound healing; but to date, there are no safety-preclinical studies concerning such type of application. Thus, in this work, biodistribution studies were performed in rats with the NLC previously developed by our research group, using technetium-99 m (99mTc-NLC) as radiomarker, topically administered on a wound. 99mTc-NLC remained on the wound for 24 h and systemic absorption was not observed after administration. In addition, toxicological studies were performed to assess NLC safety after topical administration. The results obtained demonstrated that NLC were non-cytotoxic, non-sensitizing and non-irritant/corrosive. Overall, it might be concluded that developed NLC remained at the administration area, potentially exerting a local effect, and were safe after topical administration on wounds.


Assuntos
Portadores de Fármacos/administração & dosagem , Lipídeos/administração & dosagem , Nanoestruturas/administração & dosagem , Animais , Células 3T3 BALB , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidade , Feminino , Lipídeos/farmacocinética , Lipídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos CBA , Nanoestruturas/toxicidade , Coelhos , Ratos Wistar , Pele/efeitos dos fármacos , Testes de Irritação da Pele , Tecnécio , Distribuição Tecidual , Cicatrização/efeitos dos fármacos
17.
Int J Nanomedicine ; 14: 4781-4800, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308658

RESUMO

Advancements in nanotechnology and molecular biology have promoted the development of a diverse range of models to intervene in various disorders (from diagnosis to treatment and even theranostics). Manganese dioxide nanosheets (MnO2 NSs), a typical two-dimensional (2D) transition metal oxide of nanomaterial that possesses unique structure and distinct properties have been employed in multiple disciplines in recent decades, especially in the field of biomedicine, including biocatalysis, fluorescence sensing, magnetic resonance imaging and cargo-loading functionality. A brief overview of the different synthetic methodologies for MnO2 NSs and their state-of-the-art biomedical applications is presented below, as well as the challenges and future perspectives of MnO2 NSs.


Assuntos
Tecnologia Biomédica/métodos , Compostos de Manganês/química , Nanoestruturas/química , Nanotecnologia/métodos , Óxidos/química , Técnicas Biossensoriais , Nanoestruturas/toxicidade , Óxidos/toxicidade , Tamanho da Partícula
18.
J Photochem Photobiol B ; 198: 111559, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31344503

RESUMO

Metal and metal oxide nanoparticles (NPs) possess significant properties that are promising materials for biological applications. In this research work, we prepared ionic liquid assisted Ag-Au/ZnO NPs, using J.adhatoda leaves extract by hydrothermal method. Ionic liquids performed as a stabilizing and templating agent to improve the surface morphology of the synthesized Ag and Au doped ZnO NPs. The prepared ZnO, Ag-doped ZnO, Au doped ZnO, and AgAu doped ZnO NPs exhibit the average crystalline size of 36, 34, 32, and 25 nm and their band gap energy values are 3.36, 3.29, 3.17, and 2.98 eV respectively. The XRD and UV-DRS result shows that after doping of Au and Ag the ZnO crystalline size and band gap energy was decreased, which leads to enhanced the biomedical (antibacterial and anticancer) properties of AgAu doped ZnO NPs. The Raman active mode of A1 (LO) and A1 (TO) showed that the formation of lattice defects due to the Ag and Au doping in the ZnO crystalline plane to improve the Ag-Au/ZnO properties. SEM and TEM images revealed that the prepared AgAu doped ZnO NPs exhibits nano stick shape with particle size range from 20 to 25 nm. The EDX spectrum and elemental mapping results confirmed that Ag and Au atoms are doped and spread over the ZnO NPs. The corresponding SAED pattern also confirms the crystallinity of Ag-Au/ZnO NPs. Furthermore, the synthesized Ag-Au/ZnO NPs has been explored for its antibacterial and anticancer activities. It shows good antibacterial activity against E.coli and S.aureus bacteria. Additionally, the Ag-Au/ZnO NPs show excellent anticancer activity against the HeLa cancer cells. The excellent antibacterial and anticancer results prove that the bi-metal (Ag and Au) doping can enhance the biomedical properties of ZnO NPs. It will be a promising material in the biomedical field.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Líquidos Iônicos/química , Adhatoda/química , Nanoestruturas/química , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Ouro/química , Química Verde , Células HeLa , Humanos , Adhatoda/metabolismo , Testes de Sensibilidade Microbiana , Nanoestruturas/toxicidade , Tamanho da Partícula , Extratos Vegetais/química , Espécies Reativas de Oxigênio/metabolismo , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Óxido de Zinco/química
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 221: 117150, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31176291

RESUMO

Herein, we have meticulously derived the nanosized fluorescent aggregates from pyrene Schiff base (PS) in DMSO:water (10:90) ratio. The aggregation property of PS molecule was characterized by SEM and TEM measurements, revealed the aggregated particles are in spherical shape with ~3 nm in size. Moreover, aggregates exhibit a high fluorescence quantum yield (48%) which was effectively used for the in vitro bioimaging of two different cancer cells such as A549 and MCF-7 cells in which it exhibiting excellent biocompatibility. Further, it was estimated the capability of twofold acridine orange/ethidium bromide (AO/EB) staining to identify the apoptotic associated changes in cancer cells. Additionally, the aggregates were successfully demonstrated as a luminescent probe for the perceptive biomolecule detection of bilirubin. On the other hand, the PS molecule was successfully utilized for protein binding and metal ion sensing studies. The interaction of bovine serum albumin (BSA) with PS molecule in DMSO was using fluorescence spectroscopic method and nature of interaction was also confirmed through molecular docking analysis. The PS molecule also acts as an excellent sensor for biologically important Fe3+ ion with detection limit of 336 nM. Overall, PS molecule can be a prospective material in biological field both in solution as well as aggregated forms.


Assuntos
Bilirrubina/análise , Corantes Fluorescentes/química , Ferro/análise , Pirenos/química , Soroalbumina Bovina/metabolismo , Células A549 , Laranja Acridina , Sobrevivência Celular/efeitos dos fármacos , Etídio , Corantes Fluorescentes/toxicidade , Humanos , Limite de Detecção , Células MCF-7 , Simulação de Acoplamento Molecular , Imagem Molecular/métodos , Nanoestruturas/química , Nanoestruturas/toxicidade , Tamanho da Partícula , Bases de Schiff/química , Soroalbumina Bovina/química , Espectrometria de Fluorescência
20.
Ecotoxicol Environ Saf ; 181: 345-352, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202935

RESUMO

Nanomaterials are being used increasingly in various areas such as electronic devices manufacture, medicine, mechanical devices production, and even food industry. Therefore, the evaluation of their toxicity is mandatory. Graphene oxide (GO) has been shown to have both positive as well as negative impact on different crop plants, depending on species, dose, and duration of exposure. The current study evaluated the impact of GO sheets at different concentrations (500, 1000 and 2000 mg/L) on physiological, biochemical and genetic levels to determine the possible toxic action. Wheat caryopses were treated with GO for 48 h and 7 days. The germination rate and roots elongation decreased in a dose-response manner, except the sample treated with GO at a concentration of 1000 mg/L. Mitotic index has ascendant trend; its increase may be due to the accumulation of prophases GO induced significant accumulation of the cells with aberrations, their presence suggests a clastogenic/aneugenic effect of these carbon nanomaterials. Regarding enzymatic and non-enzymatic antioxidant system defence, the activity varied depending on the dose of GO. Thus, chlorophyll a pigments content decreased significantly at high dose (2000 mg/L), while the carotenoid pigments had lower content at 500 mg/L of GO, and no statistical difference encountered in case of chlorophyll b amount. The antioxidant enzyme activity (CAT, POD, and SOD) was higher at low dose of GO, indicating the presence of oxidative stress generated as a response to the GO treatment. Also, the free radical scavenging activity of the polyphenolic compounds was enhanced upon GO exposure. The GO accumulation has been identified by transmission electron microscopy only at plumules level, near the intercellular space.


Assuntos
Grafite/toxicidade , Nanoestruturas/toxicidade , Triticum/efeitos dos fármacos , Antioxidantes/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Germinação/efeitos dos fármacos , Estresse Oxidativo , Óxidos/toxicidade , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Plântula/enzimologia , Plântula/metabolismo , Triticum/enzimologia , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
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