Enzyme‐Responsive Silica Mesoporous Supports Capped with Azopyridinium Salts for Controlled Delivery Applications. Issue 4 (7th December 2012)

• Record Type: Journal Article
• Authors: Mas, Núria; Agostini, Alessandro; Mondragón, Laura; Bernardos, Andrea; Sancenón, Félix; Marcos, M. Dolores; Martínez‐Máñez, Ramón; Costero, Ana M.; Gil, Salvador; Merino‐Sanjuán, Matilde; Amorós, Pedro; Orzáez, Mar; Pérez‐Payá, Enrique
• Is Part Of: Chemistry. Volume 19:Issue 4(2013)
• Page Start: 1346
• Page End: 1356
• Publication Date: 2012-12-07
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201202740
• Languages: English
• ISSNs: 0947-6539

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The preparation of a new capped silica mesoporous material, <bold>Rh‐Azo‐S</bold>, for on‐command delivery applications in the presence of target enzymes is described. The material consists of nanometric mesoporous MCM‐41‐like supports loaded with Rhodamine B and capped with an azopyridine derivative. The material was designed to show "zero delivery" and to display a cargo release in the presence of reductases and esterases, which are usually present in the colon, mainly due to intestinal microflora. The opening and cargo release of <bold>Rh‐Azo‐S</bold> in vitro studies were assessed and seen to occur in the presence of these enzymes, whereas no delivery was noted in the presence of pepsine. Moreover, <bold>Rh‐Azo‐S</bold> nanoparticles were used to study controlled Rhodamine B dye delivery in intracellular media. HeLa cells were employed for testing the "non"‐toxicity of nanoparticles. Moreover, delivery of the dye in these cells, through internalization and enzyme‐mediated gate opening, was confirmed by confocal microscopy. Furthermore, the nanoparticles capped with the <bold>Azo</bold> group and loaded with a cytotoxic camptothecin (<bold>CPT</bold>) were also prepared (solid <bold>CPT‐Azo‐S</bold>) and used as delivery nanodevices in HeLa cells. When this solid was employed, the cell viability decreased significantly due to internalization of the nanoparticles and delivery of the cytotoxic agent.</p> </abstract>