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1.
ACS Appl Mater Interfaces ; 15(48): 55466-55485, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37991753

RESUMO

Despite the effectiveness and selectivity of natural enzymes, their instability has paved the way for developing nanozymes with high peroxidase activity using a straightforward technique, thereby expanding their potential for multifunctional applications. Herein, meso-copper-Prussian blue microcubes (Meso-Cu-PBMCs) nanozymes were successfully prepared via a cost-effective hydrothermal route. It was found that the Cu-PBMCs nanozymes, with three-dimensional (3D) mesoporous cubic morphologies, exhibited an excellent peroxidase-like property. Based on the high affinity of Meso-Cu-PBMCs toward H2O2 (Km = 0.226 µM) and TMB (Km = 0.407 mM), a colorimetric sensor for in situ H2O2 detection was constructed. On account of the high catalytic activity, affinity, and cascade strategy, the Meso-Cu-PBMCs nanozyme generated rapid multicolor displays at varying H2O2 concentrations. Under optimized conditions, the proposed sensor exhibits a preferable sensitivity of 18.14 µA µM-1, a linear range of 10 nM-25 mM, and a detection limit of 6.36 nM (S/N = 10). The reliability of the sensor was verified by detecting H2O2 in spiked human blood serum and milk samples, as well as by detecting in situ H2O2 generated from the neuron cell SH-SY5Y. Besides, the Meso-Cu-PBMCs nanozyme facilitated the catalysis of H2O2 in cancer cells, generating •OH radicals that induce the death of cancer cells (HCT-116 colon cancer cells), which holds substantial potential for application in chemodynamic therapy (CDT). This proposed strategy holds promise for simple, rapid, inexpensive, and effective intracellular biosensing and offers a novel approach to improve CDT efficacy.


Assuntos
Peróxido de Hidrogênio , Neuroblastoma , Humanos , Glucose , Cobre , Colorimetria/métodos , Reprodutibilidade dos Testes , Peroxidase/metabolismo , Peroxidases
2.
Int J Biol Macromol ; 190: 520-532, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34480908

RESUMO

The abundance of two-dimensional (2D) components has provided them with a broad material platform for building nano and atomic-level applications. So, 2D nanomaterials are unique because of their physicochemical properties. Over many years, graphene is a conventional 2D layered element that has significant attention in the scientific community. In recent years numerous new 2D nanomaterials other than graphene have been reported. The study of 2D nanomaterials is also in its infant stages, with the majority of research focusing on the explanation of special material properties, but very few articles are focusing on the biological applications of 2D nanomaterials. As a result, we focused on the transition metal dichalcogenides (TMDCs) such as MoS2 and WS2, which were emerging and exciting groups of elements with display great opportunities in several fields, such as cancer nanomedicine. Herein, we synthesized biologically active CS/WS2/Ru composite by liquid exfoliation approach. The CS/WS2/Ru composites exhibit significant antibacterial action towards (S. aureus, and E. coli) bacteria. Also, the composite suggests synergetic anticancer action against MCF-7 cancer cells. These reports are possible to explore the innovative aspects of biological outcomes in carcinological applications.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Quitosana/química , Química Verde , Nanocompostos/química , Nanopartículas/química , Rutênio/química , Sulfetos/química , Compostos de Tungstênio/química , Bactérias/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Humanos , Células MCF-7 , Testes de Sensibilidade Microbiana , Nanocompostos/ultraestrutura , Nanopartículas/ultraestrutura , Espectroscopia Fotoeletrônica , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Propriedades de Superfície , Termogravimetria , Difração de Raios X
3.
Org Lett ; 23(4): 1383-1387, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33529042

RESUMO

A convenient and an efficient protocol for the assembly of diverse xanthenes bearing a biologically interesting oxindole nucleus is developed by utilizing the In(III)-catalyzed spiro coupling of 1,4-benzoquinones or 1,4-naphthoquinones with oxindoles. This novel protocol proceeds via a cascade of double Michael additions and intramolecular cyclization. The synthesized compounds have potential use as fluorophores for the selective imaging of heavy metals in living cells.


Assuntos
Corantes Fluorescentes/química , Índio/química , Ionóforos/química , Oxindóis/química , Quinonas/química , Xantenos/química , Catálise , Ciclização , Estrutura Molecular , Xantenos/síntese química
4.
Mater Sci Eng C Mater Biol Appl ; 111: 110791, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279742

RESUMO

Bacterial biofilm is an obstacle for wound healing because it can affect the epithelialization, development of granular cells, and other regular inflammatory procedures. It plays the role of safeguarding pathogens from antiseptics and antibiotics. In this respect, this research work aims to develop heteroatom (N, F, P/B) incorporated multi-walled carbon nanotubes (MWCNT), such as NFP-MWCNT and NFB-MWCNT, which can maximize the wound healing efficacy via destroying the wound pathogen and biofilms. NFP-MWCNT and NFB-MWCNT were obtained using self-assembling ionic liquids (ILs) such as BMIM-PF6 and BMIM-BF4 in an acid-functionalized MWCNT (A-MWCNT) suspension, followed by pyrolysis in a nitrogen atmosphere. The composite formation was established by FTIR, XRD, RAMAN, EDX mapping, and XPS spectroscopy. TEM and SEM analyses confirmed the bamboo stick-like morphology. During this reaction, IL molecules might be cross-linked with A-MWCNT via hydrogen bonding and ionic interaction, with further pyrolysis producing the defects with doping of N, F, P, or B elements. Finally, they were assessed for their antibiofilm activity against typical bacterial strains such as K. pneumoniae, P. aeruginosa, E. coli (Gram-negative), and B. subtilis (Gram-positive), using a quantitative estimation approach. The results revealed greater effectiveness of NFB-MWCNT and NFP-MWCNT, compared to pristine MWCNT. The antibiofilm activity of NFP-MWCNT and NFB-MWCNT was associated with their specific surface chemistry (due to the presence of N, F, P/B heteroatoms), and their nanosize. Moreover, the synthesized material was examined for its wound-healing ability in Wistar rats. The results proved that cells cultured on NFB-MWCNT and NFP-MWCNT displayed exceptional healing ability. The different electronegativity between the heteroatoms creates the surface charge that inhibits the biofilm formation, leading to healing the wounds together with the heteroatom mineral source for mouse fibroblast regeneration and granulation. This is the first study in which the role of different heteroatoms incorporated into MWCNT is examined in the context of antibiofilm-associated wound-healing ability.


Assuntos
Biofilmes , Imidazóis/farmacologia , Líquidos Iônicos/farmacologia , Nanocompostos/química , Nanotubos de Carbono/química , Cicatrização , Animais , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , Testes de Sensibilidade Microbiana , Nanocompostos/ultraestrutura , Nanotubos de Carbono/ultraestrutura , Espectroscopia Fotoeletrônica , Ratos Wistar , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Cicatrização/efeitos dos fármacos , Difração de Raios X
5.
J Photochem Photobiol B ; 185: 117-125, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29886330

RESUMO

The present study was aimed to investigate the antibacterial efficacy of fucoidan mediated silver nanoparticles (Fu-AgNPs) synthesized from Spatoglossum asperum. The synthesized Fu-AgNPs were characterized by UV-visible, Field emission - scanning electron microscope (FE-SEM), Tranmission electron microscope (TEM), X-ray diffraction (XRD), Selected area electron diffraction (SAED) pattern, Energy-dispersive X-ray spectroscopy (EDAX), Fourier transform infrared spectroscopy (FT-IR), Dynamic light scattering (DLS) and Zeta potential analysis. The UV-visible spectrum of Fu-AgNPs exhibited a characteristic surface plasmon resonance (SPR) peak at 440 nm. The electron microscopic results revealed that the nanoparticles were spherical to oval in shape and are found to be 20 to 46 nm. Altogether the X-ray diffraction analysis showed that the Fu-AgNPs were crystalline in nature. The FT-IR spectrum confirmed the existence of CC stretching vibration of aromatic compounds and sulfated groups of fucoidan plays a major role in the synthesis of Fu-AgNPs. The biosynthesized Fu-AgNPs shows potential antibacterial activity against Klebsiella pneumoniae in agar bioassay, disk diffusion, reactive oxygen species, protein leakage and confocal laser scanning microscopy assays. Furthermore, Artemia toxicity assay results showed less mortality (3.3 ±â€¯0.8%) even at higher concentration of Fu-AgNPs. Therefore, Fu-AgNPs can be effectively used as an antibacterial agent in the pharmaceutical fields.


Assuntos
Antibacterianos/síntese química , Nanopartículas Metálicas/química , Phaeophyceae/metabolismo , Polissacarídeos/química , Prata/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Artemia/efeitos dos fármacos , Artemia/crescimento & desenvolvimento , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Química Verde , Klebsiella pneumoniae/efeitos dos fármacos , Luz , Nanopartículas Metálicas/toxicidade , Microscopia Confocal , Extratos Vegetais/química , Polissacarídeos/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
Artigo em Inglês | MEDLINE | ID: mdl-25613692

RESUMO

In the present study, we have synthesized silver nanoparticles by a simple and eco-friendly method using unripe fruits of Solanum trilobatum. The aqueous silver ions when exposed to unripe fruits extract were reduced and stabilized over long time resulting in biosynthesis of surface functionalized silver nanoparticles. The bio-reduced silver nanoparticles were characterized by UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDX) and X-ray diffraction (XRD). These biologically synthesized silver nanoparticles were tested for its antibacterial activity against few human pathogenic bacteria including Gram-positive (Streptococcus mutans, Enterococcus faecalis) and Gram-negative (Escherichia coli, Klebsiella pneumoniae) bacteria. In addition, we also demonstrated anticancer activity of these nanoparticles in vitro against human breast cancer cell line (MCF 7) using MTT, nuclear morphology assay, Western blot and RT-PCR expression. These results taken together show the potential applications of biosynthesized silver nanoparticles using S. trilobatum fruits.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Nanopartículas Metálicas/química , Prata/química , Solanum/química , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Mama/efeitos dos fármacos , Mama/patologia , Neoplasias da Mama/patologia , Feminino , Frutas/química , Química Verde , Humanos , Células MCF-7 , Nanopartículas Metálicas/uso terapêutico , Prata/farmacologia
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