RESUMO
Abstract Silver nanoparticles (AgNPs) are among the most known nanomaterials being used for several purposes, including medical applications. In this study, Calendula officinalis L. flower extract and silver nitrate were used for green synthesis of silver nanoparticles under red, green and blue light-emitting diodes. AgNPs were characterized by Ultraviolet-Visible Spectrophotometry, Field Emission Scanning Electron Microscopy, Dynamic Light Scattering, Electrophoretic Mobility, Fourier Transform Infrared Spectroscopy and X-ray Diffraction. Isotropic and anisotropic silver nanoparticles were obtained, presenting hydrodinamic diameters ranging 90 - 180 nm, polydispersity (PdI > 0.2) and moderate stability (zeta potential values around - 20 mV)
Assuntos
Prata , Nitrato de Prata/agonistas , Calendula/efeitos adversos , Flores/genética , Nanopartículas/análise , Espectrofotometria/métodos , Difração de Raios X/métodos , Microscopia Eletrônica de Varredura/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , LuzRESUMO
Legumain, a kind of asparaginyl endopeptidase, is overexpressed in highly metastatic and highly aggressive tumor, which can undergo an enzymatic hydrolysis of substrates. We proposed a legumain-responsive functional gold nanoparticle (GNP) drug delivery system (GNPs-A&C), which was consist of Ala-Ala-Asn-Cys-Lys (AK) modified GNPs (GNPs-AK) and 2-cyano-6-aminobenzothiazole (CABT) modified GNPs (GNPs-CABT). In the circulation system, the GNPs-A&C could passively target to the tumor site through the enhanced permeability and retention (EPR) effect. Then the overexpressed legumain specifically cleave the peptide to exposure the 1,2-thiolamino group, which could take place click reaction with the cyano group of CABT, leading to the aggregation of two GNPs, these aggregates of GNPs with increased size were more likely to retain within tumor site. In vivo fluorescent imaging demonstrated GNPs-A&C could acquire an enhanced accumulation in legumain-overexpressed C6 tumor. Importantly, after tethering DOX, the GNPs-DOX-A&C showed an excellent anti-tumor effect with reduced cardiotoxicity.