Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Biosens Bioelectron ; 171: 112717, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33059169

RESUMEN

This paper reports a new biocompatible conductivity enhancement of poly (3,4-ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) films for biomedical applications. Conductivity of PEDOT:PSS layer was reproducibly from 0.495 to 125.367 S cm-1 by hydrothermal (HT) treatment. The HT treatment employs water (relative humidity > 80%) and heat (temperature > 61 °C) instead of organic solvent doping and post-treatments, which can leave undesirable residue. The treatment can be performed using the sterilizing conditions of an autoclave. Additionally, it is possible to simultaneously reduce the electrical resistance, and sterilize the electrode for practical use. The key to conductivity enhancement was the structural rearrangement of PEDOT:PSS, which was determined using atomic force microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and ultraviolet-visible spectroscopy. It was found that PEDOT inter-bridging occurred as a result of the structural rearrangement. Therefore, the conductivity increased on account of the continuous conductive pathways of the PEDOT chains. To test the biocompatible enhancement technique for biomedical applications, certain demonstrations, such as the monitoring of joint movements and skin temperature, and measuring electrocardiogram signals were conducted with the hydrothermal-treated PEDOT:PSS electrode. This simple, biocompatible treatment exhibited significant potential for use in other biomedical applications as well.


Asunto(s)
Técnicas Biosensibles , Poliestirenos , Compuestos Bicíclicos Heterocíclicos con Puentes , Conductividad Eléctrica , Polímeros
2.
Pharmaceutics ; 11(10)2019 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-31614927

RESUMEN

A new system for the easy loading and NIR light-triggered release of drugs is introduced. It consists of poly(ε-caprolactone) (PCL) hollow nanoparticles with surface openings containing a biodegradable fatty acid with phase-change ability and a biocompatible photothermal agent. These openings, which can enhance the connectivity between the interior and the exterior, enable the easy loading of drug molecules into the interior voids, and their successive sealing ensures a stable encapsulation of the drug. Upon exposure to an external NIR light irradiation, the photothermal agent generates heat that raises the local temperature of the hollow particles above the melting point of the fatty acid, leading to the formation of nanopores on their shells, and consequently, the instant release of the encapsulated drug molecules through the pores. The synergistic activity of the hyperthermia effect from the photothermal agent and the NIR-triggered release of the drug molecules results in noticeable anticancer efficacy.

3.
Pharmaceutics ; 11(2)2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30717084

RESUMEN

This paper introduces a new fibrous system for synergistic cancer therapy, which consists of gold nanocage (AuNC)-loaded poly(ε-caprolactone) (PCL) fibers with encapsulation of a chemotherapeutic anticancer drug in their core and loading of a phase-changeable fatty acid in their sheath. Under on⁻off switching of near-infrared (NIR) light irradiation, the excellent photothermal ability and photostability of AuNCs allows repeated, significant heating of the fibers to a temperature available to hyperthermia. Simultaneously, the NIR light-induced heat generation enables the melting out of the loaded fatty acid, leading to a rapid release of the drug molecules from the fibers. The combination of this NIR light-triggered drug release with the repeated hyperthermia treatment exhibits excellent anticancer efficacy.

4.
Colloids Surf B Biointerfaces ; 173: 258-265, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30300832

RESUMEN

This work introduces a new fibrous system for synergistic cancer therapy. The system consists of poly(d,l-lactic-co-glycolic acid) (PLGA) fibers with a core encapsulating an anticancer drug and a shell entrapping gold nanorods (AuNRs) as a photothermal agent. On exposure to NIR light, the photothermal agent generates heat to raise the local temperature of the fibers. If the temperature is above a glass transition (Tg) of the polymer, the polymer chains will be mobile, increasing free volume in size within the shell. As a result, a rapid release of the drug can be achieved. When NIR light is turned off, the release will stop with inactivity of the photothermal agent, followed by freezing the segmental motion of the polymer chains. The on-off switching of NIR light in a time-controllable manner allows a repeated and accurate release of the drug, leading to the significant enhancement of anticancer activity in combination with the hyperthermia effect arising from the photothermal agent.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Preparaciones de Acción Retardada , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas del Metal/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Antibióticos Antineoplásicos/química , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Cetrimonio/química , Doxorrubicina/química , Composición de Medicamentos/métodos , Liberación de Fármacos , Técnicas Electroquímicas , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Células Epiteliales/efectos de la radiación , Femenino , Oro/química , Humanos , Hipertermia Inducida/métodos , Rayos Infrarrojos , Cinética , Terapia por Luz de Baja Intensidad/métodos , Nanopartículas del Metal/ultraestructura , Nanotubos/química , Nanotubos/ultraestructura
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA