A molecular model to explain the controlled release from SBA-15 functionalized with APTES

A molecular model with the approximate pore diameter of SBA-15 was constructed for the first time to investigate the effect of functionalize the matrix with 3-aminopropyl-triethoxy-silane (APTES) in the release of Chicago Sky Blue 6B (CSB). It was expected that the positively charged amino groups of...

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Detalles Bibliográficos
Autores: Doadrio Villarejo, Antonio Luis, Sánchez Montero, José, Doadrio Villarejo, Juan Carlos, Salinas Sánchez, Antonio Jesús, Vallet Regí, María Dulce Nombre
Tipo de recurso: artículo
Fecha de publicación:2014
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/35408
Acceso en línea:https://hdl.handle.net/20.500.14352/35408
Access Level:acceso abierto
Palabra clave:546
615.46
Molecular modelling
Mesoporous SBA-15
APTES functionalization
Chicago Sky Blue 6B
Kinetics of release
Materiales
Química inorgánica (Química)
3312 Tecnología de Materiales
2303 Química Inorgánica
Descripción
Sumario:A molecular model with the approximate pore diameter of SBA-15 was constructed for the first time to investigate the effect of functionalize the matrix with 3-aminopropyl-triethoxy-silane (APTES) in the release of Chicago Sky Blue 6B (CSB). It was expected that the positively charged amino groups of APTES could interact with the negatively charged sulphonic groups of CSB allowing controlling the release process. Indeed the experimental study showed that the release kinetics of CSB from SBA-15-APTES is two orders of magnitude smaller than from native SBA-15. However molecular modelling calculations investigating the possible interactions of APTES and SBA-15 yield unexpected results. In the model including only the condensation between the silanol groups of SBA-15 and APTES, the calculated interaction energy of CSB was quite similar than with the model of native SBA-15. However when additional electrostatic interactions of the -NH2 groups of APTES with the mesoporous matrix were modelled the mesoporous channels underwent a considerable deformation. These results point to the structure deformation as the cause of the greater retention of CSB in SBA-15-APTES and warn about the special features of AFTES when used to functionalize mesoporous silica materials. The model built in this paper could be used to construct predictive models in analogous drug delivery systems. (C) 2014 Elsevier Inc. All rights reserved.