ß-Cristobalite (001) surface as 4-formaminoantipyrine adsorbent: First principle study of the effect on adsorption of surface modification

Silica based materials find applications as excipients and particularly as drug delivery agents for pharmaceutical drugs. Their performance can be crucially affected by surface treatments, as it can modify the adsorption (and release) of these formulations. The role of surface modification on the fe...

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Bibliographic Details
Authors: Simonetti, S., Díaz Compañy, Andrés Carlos Daniel, Brizuela, G, Juan, A.
Format: article
Status:Published version
Publication Date:2016
Country:Argentina
Institution:Comisión de Investigaciones Científicas de la Provincia de Buenos Aires
Repository:CIC Digital (CICBA)
Language:English
OAI Identifier:oai:digital.cic.gba.gob.ar:11746/8205
Online Access:https://digital.cic.gba.gob.ar/handle/11746/8205
Access Level:Open access
Keyword:Ciencias Físicas
H-bond
Dispersion force
Adsorption
Functionalization
FAA
Silica
DFT
Description
Summary:Silica based materials find applications as excipients and particularly as drug delivery agents for pharmaceutical drugs. Their performance can be crucially affected by surface treatments, as it can modify the adsorption (and release) of these formulations. The role of surface modification on the features of 4-formaminoantipyrine (FAA) adsorbed on ß-cristobalite (001) surface is studied by means of simulations based on the Density Functional Theory (DFT). Starting from the results of FAA in interaction with a dehydroxylated surface; a fully hydroxylated surface and a functionalized surface with benzalkonium chloride (BC) surfactant have been added to study the configurational landscape. Calculations suggest that the trend for FAA preferential adsorption on silica surfaces is: dehydroxylated >hydroxylated > BCfunctionalized. The potential for hydrogen bonding causes the main contribution to the bonding while dispersion forces present an additional contribution independently of whether the drug is hydrogenbonded or BC-bonded to the surface. Adsorption takes mainly place through nitrogen atoms in the heterocyclic ring, the carbonyl and amine functional groups. Associated mode’s shifts and concurrent changes in bond length are also observed showing accordance between electronic and geometrical structure results. BC surfactant reduces the number of formed H-bonds and lowers the attractive molecule-surface interaction being it useful to prevent particle agglomeration and could favor drug release in therapies that requires faster but controlled delivery.