title: Poly(propylene imine) dendrimer caps on mesoporous silica nanoparticles for redox-responsive release: smaller is better.
abstract: To elucidate the importance of the size of capping agents in stimulus-induced release systems from mesoporous silica nanoparticles (MSNs), the effectiveness of poly(propylene imine) dendrimers in controlling the model drug release was studied. MCM-41-type MSNs were synthesized and characterized. Fluorescent compounds (fluorescein disodium salt and carboxyfluorescein) were loaded in the porous structure of the MSNs and entrapped in the silica matrix with the dendrimers of generations I through V by anchoring dendrimers on the MSN surface through disulfide bonds. Stimulus-induced release of the cargo was studied in the presence of dithiothreitol (DTT). Dendrimers of generations I and II were found to be more effective in model drug retention and subsequent release than higher generations. Moreover, MSNs modified with larger amounts of dendrimers lowered the cargo release in the presence of DTT. These findings are of importance for optimizing drug delivery systems based on responsive MSNs as they enable tuning of the amount of the released cargo by choosing the capping agent of appropriate size.
authors.affiliation: National Institute of Chemistry, Hajdrihova ul. 19, 1000 Ljubljana, Slovenia.
authors.forename: Peter
authors.initials: P
authors.lastname: Nadrah
authors.forename: Fabiola
authors.initials: F
authors.lastname: Porta
authors.forename: Odon
authors.initials: O
authors.lastname: Planinšek
authors.forename: Alexander
authors.initials: A
authors.lastname: Kros
authors.forename: Miran
authors.initials: M
authors.lastname: Gaberšček
mesh_terms: D050091:Dendrimers / Q000737:chemistry*; D004229:Dithiothreitol / Q000737:chemistry; D004337:Drug Carriers / Q000737:chemistry; D019793:Fluorescein / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry*; D010084:Oxidation-Reduction; D011126:Polypropylenes / Q000737:chemistry*; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D050091:Dendrimers; D004337:Drug Carriers; C509968:MCM-41; D011126:Polypropylenes; C443641:poly(propyleneimine); D012822:Silicon Dioxide; D004229:Dithiothreitol; D019793:Fluorescein