RESUMO
Chemo-photothermal therapy based on nanoparticles has emerged as a promising strategy for cancer treatment. However, its therapeutic efficacy and application potential are largely subjected to the uncontrollability and biotoxicity of functional nanoplatforms. Herein, a novel biocompatible and biodegradable metal organic framework (MOF), which was constructed by growing crystalline zeolitic imidazolate framework-8 on gold nanoroad (Au@ZIF-8), was designed and fabricated for efficient drug loading and controlled release. Owing to the large surface area and guest-matching pore size of ZIF-8, doxorubicin (DOX) was successfully loaded into the Au@ZIF-8 with a high drug loading efficiency of ~ 37%. Under NIR light or weakly acidic environment, the ZIF-8 layer was quickly degraded, which resulted in an on-demand drug release in tumour site. More importantly, under the irradiation of near infrared (NIR) laser, highly efficient cancer treatment was achieved in both in vitro cell experiment and in vivo tumour-bearing nude mice experiment due to the synergistic effect of photothermal (PTT) therapy and chemotherapy. In addition, the in vivo study revealed the good biocompatibility of Au@ZIF-8. This work robustly suggested that Au@ZIF-8 could be further explored as a drug delivery system for chemo-photothermal synergistic therapy.
Assuntos
Sistemas de Liberação de Medicamentos , Ouro/química , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Nanotubos/química , Terapia Fototérmica/métodos , Animais , Materiais Biocompatíveis , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Células HeLa , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/tratamento farmacológico , Tamanho da Partícula , Preparações FarmacêuticasRESUMO
A miniature quartz crystal microbalance (mQCM) was integrated with a polydimethylsiloxane (PDMS) microfluidic device for on-chip determination of amyloid polypeptide-Aß42. The integration techniques included photolithography and plasma coupling. Aß42 antibody was immobilized on the mQCM surface using a cross-linker method, and the resonance frequency of mQCM shifted negatively due to antibody-antigen binding. A linear range from 0.1 µM to 3.2 µM was achieved. By using matrix elimination buffer, i.e., matrix phosphate buffer containing 500 µg/mL dextran and 0.5% Tween 20, Aß42 could be successfully detected in the presence of 75% human serum. Additionally, high temperature treatments at 150 °C provided a valid method to recover mQCM, and PDMS-mQCM microfluidic device could be reused to some extent. Since the detectable Aß42 concentration could be as low as 0.1 µM, which is close to cut-off value for Alzheimer patients, the PDMS-mQCM device could be applied in early Alzheimer's disease diagnosis.
Assuntos
Peptídeos beta-Amiloides/sangue , Técnicas Analíticas Microfluídicas/instrumentação , Fragmentos de Peptídeos/sangue , Técnicas de Microbalança de Cristal de Quartzo/instrumentação , Dimetilpolisiloxanos , Desenho de Equipamento , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Técnicas de Microbalança de Cristal de Quartzo/métodos , Reprodutibilidade dos TestesRESUMO
Hydroxyapatite (HA) coatings directly deposited by hydrothermal electrochemical technology (HET) onto carbon/carbon (C/C) composites exhibited a catastrophic failure occurring at the interface of the HA and C/C. To overcome this problem, a polyvinyl alcohol (PVA)/graphene oxide (GO) interlayer (P/G interlayer) was applied on the (NH4)2S2O8-pretreated C/C substrate (named P/G-C/C) by using a dipping method. Subsequently, a calcium phosphate coating was deposited on P/G-C/C, shortened as M-P/G-C/C, by HET, and then converted into HA coating (abbreviated as HA-P/G-C/C) through posthydrothermal treatment. For comparison, HA coating was prepared onto C/C without a P/G interlayer through the same process, which was denoted as HA-C/C. The composition, microstructure, and morphology of the samples were characterized by X-ray diffractometry (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), Raman spectra, Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS). The adhesive performance of the coatings on C/C was measured by a scratch test. Finally, an in vitro bioactivity of the coatings was evaluated in a simulated body fluid solution at 37 °C. Results showed no apparent differences in the morphology and phase of the posttreated coatings, both of which are composed of a dense structure containing needle-like HA crystals. However, the HA-P/G-C/C sample possessed a higher Ca/P ratio and denser interface, thereby exhibiting higher adhesive performance and better bioactivity. The adhesive strength of the HA-P/G coating was observed at a critical load of 41.04 N, which increased by 29.3% relative to the HA coating. Moreover, the failure site was on the HA-P/G coating rather than at the interface. The enhanced adhesive performance was ascribed to the PVA/GO-repairing pits on C/C and PVA and GO toughening effects on the HA coating. In vitro and in vivo tests revealed no statistical significance for the two HA-coated C/C samples, although the HA-P/G coating exhibited better bioactivity, inducing the growth of bonelike apatite than the HA coating.
Assuntos
Carbono/química , Materiais Revestidos Biocompatíveis/química , Durapatita/química , Grafite/química , Álcool de Polivinil/química , Animais , Doenças Ósseas/patologia , Doenças Ósseas/terapia , Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/química , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/uso terapêutico , Galvanoplastia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Próteses e Implantes , Ratos , Ratos Sprague-Dawley , Propriedades de SuperfícieRESUMO
Carbon/carbon composite with hydroxyapatite (HA) coating is an attractive material in the dental and orthopedic fields, but the reported bonding strength between them was very poor. In this study, a compact crystalline HA coating on (NH(4))(2)S(2)O(8)-treated C/C substrate about 10 microm in width was obtained by hydrothermal treatment and induction heating. The microstructure, composition and morphologies of the as-prepared coatings were identified by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. A strong shear strength averaging 74.2 MPa between C/C substrate and HA was achieved and adhesion failures were observed more frequently than cohesion failures. The coating adhesion measured using a scratch test was 23 N and the reasons for this are discussed.