Influence of pH on cephalexin adsorption onto SBA-15 mesoporous silica: Theoretical and experimental study

tCephalexin adsorption from aqueous solutions using SBA-15 mesoporous silica as adsorbent and theinfluence of pH solution on drug adsorption were studied. In order to have a better knowledge aboutthe way the drug molecules interact with the inorganic matrix, the adsorption process was estimatedby ap...

ver descrição completa

Detalhes bibliográficos
Autores: Legnoverde, María Soledad, Simonetti, Sandra Isabel, Basaldella, Elena I.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2014
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/7559
Acesso em linha:http://hdl.handle.net/11336/7559
Access Level:acceso abierto
Palavra-chave:Mesoporous Materials
Adsorption
Computer Modeling And Simulation
https://purl.org/becyt/ford/2.5
https://purl.org/becyt/ford/2
Descrição
Resumo:tCephalexin adsorption from aqueous solutions using SBA-15 mesoporous silica as adsorbent and theinfluence of pH solution on drug adsorption were studied. In order to have a better knowledge aboutthe way the drug molecules interact with the inorganic matrix, the adsorption process was estimatedby applying the computational chemistry software YAeHMOP (Yet Another extended Hückel Molec-ular Orbital Package). A strong correlation between the theoretical calculations and the experimentalresults was established, showing that the adsorbate?adsorbent interaction is pH dependent. Calculatedcephalexin horizontal adsorption energy was almost 9 eV more stable than the one corresponding tovertical adsorption, and also the lowest enthalpy of contact and the maximum adsorption percent werefound for the cationic cephalexin?silica system. Cephalexin adsorption through the NH3+group is 8 eVstronger than the molecule adsorption through the COO−group. In agreement with these theoreticalpredictions, experimental results indicate that the electrostatic attraction between CPX ions and the sur-face of mesoporous silica is favored at pH values between 2 and 2.56, the maximum being for cephalexinadsorption obtained at pH 2.3.