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1.
Langmuir ; 29(10): 3453-66, 2013 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-23409925

RESUMO

A multifunctional biocompatible nanovector based on magnetic nanoparticle and carboxymethyl cellulose (CMC) was developed. The nanoparticles have been characterized using TEM, SEM, DLS, FT-IR spectra, VSM, and TGA studies. We found that the synthesized carboxymethyl cellulose magnetic nanoparticles (CMC MNPs) were spherical in shape with an average size of 150 nm having low aggregation and superparamagnetic properties. We found that the folate-tagged CMC MNPs were delivered to cancer cells by a folate-receptor-mediated endocytosis mechanism. 5-FU was encapsulated as a model drug for delivering cytotoxicity, and we could demonstrate the sustained release of 5-FU. It was also observed that the FITC-labeled CMC MNPs could effectively enter cells, and the fate of nanoparticles was tracked with Lysotracker. The CMC MNPs could induce significant cell death when an alternating magnetic field was applied. These results indicate that the multifunctional CMC MNPs possess a high drug loading efficiency and high biocompatibility and with low cell cytotoxicity and can be considered to be promising candidates for CMC-based targeted drug delivery, cellular imaging, and magnetic hyperthermia (MHT).


Assuntos
Carboximetilcelulose Sódica/química , Magnetismo , Nanopartículas/química , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fluoresceína-5-Isotiocianato , Fluoruracila/química , Fluoruracila/farmacologia , Receptores de Folato com Âncoras de GPI , Humanos , Hipertermia Induzida , Nanopartículas/uso terapêutico , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Anal Bioanal Chem ; 397(4): 1417-35, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20349348

RESUMO

Developments in nanotechnology have paved the way for the early detection, treatment, and prevention of several tumors which affect mankind. In the past few years, near-infrared (NIR) fluorescence imaging techniques have emerged that enable the in vivo imaging of physiological, metabolic, and molecular function. The NIR window, also known as the diagnostic window (700-900 nm), can be explored for sensitive detection techniques. Nanoparticles, particularly semiconductor quantum dots (QDs), can be utilized for the purpose of optical imaging. These semiconductor QDs possess novel electronic, optical, magnetic, and structural properties which are quite different from those of bulk materials. NIR QDs with these unique properties can be utilized as contrast agents for optical imaging, particularly for deep tissue imaging. Deep tissue imaging provides more information about the pathological status of the disease, which makes the treatment more effective and efficient. In this review we highlight the importance of NIR QDs as probes for optical imaging. We describe the different types of NIR QDs, their synthesis, and their application for deep tissue imaging along with recently developed self-illuminating NIR QDs.


Assuntos
Diagnóstico por Imagem/métodos , Imagem Molecular/métodos , Pontos Quânticos , Animais , Corantes Fluorescentes/química , Humanos , Espectroscopia de Luz Próxima ao Infravermelho , Distribuição Tecidual
3.
Biomater Sci ; 5(3): 432-443, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-28059418

RESUMO

We have designed versatile polymeric nanoparticles with cancer cell specific targeting capabilities via aptamer conjugation after the successful encapsulation of curcumin and superparamagnetic iron oxide nanoparticles (SPIONs) inside a PLGA nanocapsule. These targeted nanocomposites were selectively taken up by tumor cells, under in vitro conditions, demonstrating the effectiveness of the aptamer targeting mechanism. Moreover, the nanocomposite potentially functioned as efficient multiprobes for optical, magnetic resonance imaging (MRI) and photoacoustic imaging contrast agents in the field of cancer diagnostics. The hyperthermic ability of these nanocomposites was mediated by SPIONs upon NIR-laser irradiation. In vitro cytotoxicity was shown by curcumin-loaded nanoparticles as well as the photothermal ablation of cancer cells mediated by the drug-encapsulated nanocomposite demonstrated the potential therapeutic effect of the nanocomposite. In short, we portray the aptamer-conjugated nanocomposite as a multimodal material capable of serving as a contrast agent for MR, photoacoustic and optical imaging. Furthermore, the nanocomposite functions as a targetable drug nanocarrier and a NIR-laser inducible hyperthermic material that is capable of ablating PANC-1 and MIA PaCa-2 cancer cell lines.


Assuntos
Aptâmeros de Nucleotídeos/química , Meios de Contraste/química , Ácido Láctico/química , Nanopartículas de Magnetita/química , Nanocompostos/química , Neoplasias/diagnóstico por imagem , Ácido Poliglicólico/química , Linhagem Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Imagem Óptica/métodos , Técnicas Fotoacústicas/métodos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
4.
J Biomed Nanotechnol ; 10(6): 885-99, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24749386

RESUMO

Microbial exopolysaccharides (EPSs) are highly heterogeneous polymers produced by fungi and bacteria that have garnered considerable attention and have remarkable potential in various fields, including biomedical research. The necessity of biocompatible materials to coat and stabilize nanoparticles is highly recommended for successful application of the same in biomedical regime. In our study we have coated magnetic nanoparticles (MNPs) with two bacterial EPS-mauran (MR) and gellan gum (GG). The biocompatibility of EPS coated MNPs was enhanced and we have made it multifunctional by attaching targeting moiety, folate and with encapsulation of a potent anticancerous drug, 5FU. We have conjugated an imaging moiety along with nanocomposite to study the effective uptake of nanoparticles. It was also observed that the dye labeled folate targeted nanoparticles could effectively enter into cancer cells and the fate of nanoparticles was tracked with Lysotracker. The biocompatibility of EPS coated MNPs and synergistic effect of magnetic hyperthermia and drug for enhanced antiproliferation of cancer cells was also evaluated. More than 80% of cancer cells was killed within a period of 60 min when magnetic hyperthermia (MHT) was applied along with drug loaded EPS coated MNPs, thus signifying the combined effect of drug loaded MNPs and MHT. Our results suggests that MR and GG coated MNPs exhibited excellent biocompatibility with low cell cytotoxicity, high therapeutic potential, and superparamagnetic behavior that can be employed as prospective candidates for bacterial EPS based targeted drug delivery, cancer cell imaging and for MHT for killing cancer cells within short period of time.


Assuntos
Fluoruracila/administração & dosagem , Nanopartículas de Magnetita/uso terapêutico , Terapia de Alvo Molecular/métodos , Nanocápsulas/química , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Polissacarídeos Bacterianos/química , Animais , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/química , Linhagem Celular Tumoral , Rastreamento de Células/métodos , Terapia Combinada , Sinergismo Farmacológico , Fluoruracila/química , Humanos , Hipertermia Induzida , Nanopartículas de Magnetita/química , Camundongos , Nanocápsulas/uso terapêutico , Resultado do Tratamento
5.
Int J Biomater ; 2012: 345029, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22481938

RESUMO

Design of blood compatible surfaces is required to minimize platelet surface interactions and increase the thromboresistance of foreign surfaces when they are used as biomaterials especially for artificial blood prostheses. In this study, single wall carbon nanotubes (SWCNTs) and Zein fibrous nanocomposite scaffolds were fabricated by electrospinning and evaluated its antithrombogenicity and hydrophilicity. The uniform and highly smooth nanofibers of Zein composited with different SWCNTs content (ranging from 0.2 wt% to 1 wt%) were successfully prepared by electrospinning method without the occurrence of bead defects. The resulting fiber diameters were in the range of 100-300 nm without any beads. Composite nanofibers with and without SWCNT were characterized through a variety of methods including scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, and tensile mechanical testing. The water uptake and retention ability of composite scaffolds decreased whereas thermal stability increased with an addition of SWCNTs. Hemolytic property and platelet adhesion ability of the nanocomposite (Zein-SWCNTs) were explored. These observations suggest that the novel Zein-SWCNTs composite scaffolds may possibly hold great promises as useful antithrombotic material and promising biomaterials for tissue engineering application.

6.
Biomed Mater ; 7(4): 045001, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22556150

RESUMO

Nanomedicine utilizes engineered nanodevices and nanostructures for monitoring, repair, construction and control of human biological systems at the molecular level. In this study, we investigated the feasibility and potential of zein nanofiber as a delivery vehicle for curcumin in biomedical applications. By optimizing the electrospinning parameters, ultrafine zein fluorescence nanofibers containing curcumin were developed with interconnected fibrous networks. We found that these nanofibers show an increase in fluorescence due to the incorporation of curcumin. The morphology and material properties of the resulting multifunctional nanofiber including the surface area were examined by a field emission-scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and confocal microscopy. The surface area and pore size were characterized by N(2) adsorption-desorption isotherm. SEM and fluorescence images showed that the uniform fibers with smooth surface had an average diameter of about 310 nm. An in vitro degradation study showed significant morphological changes. The in vitro evaluations suggested that the curcumin incorporated zein nanofibers showed sustained release of curcumin and maintained its free radical scavenging ability. It provides an attractive structure for the attachment and growth of fibroblast as cell culture surfaces. The results demonstrate that the curcumin loaded zein nanofiber could be a good candidate for soft tissue engineering scaffolds and has the potential for further applications in drug delivery system.


Assuntos
Curcumina/administração & dosagem , Sistemas de Liberação de Medicamentos , Nanofibras/química , Zeína/química , Antioxidantes/química , Materiais Biocompatíveis/química , Técnicas de Cultura de Células , Fibroblastos/citologia , Sequestradores de Radicais Livres , Radicais Livres , Humanos , Microscopia Confocal/métodos , Microscopia Eletrônica de Varredura/métodos , Nanomedicina/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Termogravimetria/métodos , Engenharia Tecidual
7.
Appl Biochem Biotechnol ; 151(2-3): 244-55, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18592412

RESUMO

Lactic acid bacteria were isolated from fermented vegetables, sour dough, milk products, sheep and human excreta. The newly isolated cultures were evaluated for a number of probiotic characteristics like bile salt resistance, salt tolerance in general, survival in low pH, hydrophobicity of the cell surface, resistance to low phenol concentration, antimicrobial activity and susceptibility pattern against vancomycin and erythromycin. The selected cultures were further screened for their ability to produce the nutraceticals such as folic acid and exopolysaccharide (EPS). Two potent isolates, CB2 (from cabbage) and SD2 (from sour dough) were found to produce both extracellular and intracellular folate. One of the isolates from yogurt (MC-1) and the one from whey (W3) produced significant amount of EPS with a maximum production of 8.79 +/- 0.05 g/l by MC-1.


Assuntos
Bactérias/isolamento & purificação , Microbiologia de Alimentos , Ácido Láctico/metabolismo , Probióticos/farmacologia , Bactérias/efeitos dos fármacos , Suplementos Nutricionais , Farmacorresistência Bacteriana , Fezes/microbiologia , Ácido Fólico/biossíntese , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lactente , Testes de Sensibilidade Microbiana , Fenol/farmacologia , Polissacarídeos Bacterianos/biossíntese , Tolerância ao Sal , Ácido Taurocólico/farmacologia
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