RESUMO
Effective and controlled drug delivery systems with on-demand release and targeting abilities have received enormous attention for biomedical applications. Here, we describe a novel enzyme-based cap system for mesoporous silica nanoparticles (MSNs) that is directly combined with a targeting ligand via bio-orthogonal click chemistry. The capping system is based on the pH-responsive binding of an aryl-sulfonamide-functionalized MSN and the enzyme carbonic anhydrase (CA). An unnatural amino acid (UAA) containing a norbornene moiety was genetically incorporated into CA. This UAA allowed for the site-specific bio-orthogonal attachment of even very sensitive targeting ligands such as folic acid and anandamide. This leads to specific receptor-mediated cell and stem cell uptake. We demonstrate the successful delivery and release of the chemotherapeutic agent Actinomycin D to KB cells. This novel nanocarrier concept provides a promising platform for the development of precisely controllable and highly modular theranostic systems.
Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Transporte Biológico Ativo , Anidrase Carbônica II/química , Anidrase Carbônica II/genética , Anidrase Carbônica II/metabolismo , Linhagem Celular , Dactinomicina/administração & dosagem , Dactinomicina/farmacocinética , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Células HeLa , Humanos , Células KB , Camundongos , Nanopartículas/química , Engenharia de Proteínas , Receptores de Droga/química , Receptores de Droga/genética , Receptores de Droga/metabolismo , Dióxido de SilícioRESUMO
We report the development of dendritic siRNA nanostructures that are able to penetrate even difficult to transfect cells such as neurons with the help of a special receptor ligand. The nanoparticles elicit strong siRNA responses, despite the dendritic structure. An siRNA dendrimer directed against the crucial rabies virus (RABV) nucleoprotein (Nâ protein) and phosphoprotein (Pâ protein) allowed the suppression of the virus titer in neurons below the detection limit. The cell-penetrating siRNA dendrimers, which were assembled using click chemistry, open up new avenues toward finding novel molecules able to cure this deadly disease.
Assuntos
Dendrímeros , Nanoestruturas , RNA Interferente Pequeno/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Significant differences in the reactivity of norbornene derivatives in the inverse electron-demand Diels-Alder reaction with tetrazines were revealed by kinetic studies. Substantial rate enhancement for the exo norbornene isomers was observed. Quantum-chemical calculations were used to rationalize and support the observed experimental data.