Please use this identifier to cite or link to this item:
Scopus Web of Science® Altmetric
Type: Journal article
Title: Surface-functionalized diatom microcapsules for drug delivery of water-insoluble drugs
Author: Aw, M.
Bariana, M.
Yu, Y.
Addai-Mensah, J.
Losic, D.
Citation: Journal of Biomaterials Applications, 2013; 28(2):163-174
Publisher: Technomic Publishing Company
Issue Date: 2013
ISSN: 0885-3282
Statement of
Moom Sinn Aw, Manpreet Bariana, Yang Yu, Jonas Addai-Mensah and Dusan Losic
Abstract: Naturally available and biocompatible materials are potential substitutes for synthetic mesoporous materials as suitable drug carriers for the development of cost-effective drug delivery systems. This work investigates the application of a porous silica material derived from diatoms, also known as diatomaceous earth. The aim is to explore the surface functionalization of diatom microcapsules and their impact on the drug loading and release characteristics of water-insoluble drugs. Indomethacin was used as the model for poorly soluble drug. The surface modification on diatoms was performed with two organosilanes; 3-aminopropyltriethoxy silane and N-(3-(trimethoxysilyl) propyl) ethylene diamine and phosphonic acids (2-carboxyethyl-phosphonic acid and 16-phosphono-hexadecanoic acid) providing organic surface hydrophilic and hydrophobic properties. Extensive characterizations using scanning electron microscopy, X-ray photoelectron spectroscopy and differential scanning calorimetry was performed to confirm covalent grafting of monolayer aminosilane and phosphonic acid on the diatom surfaces. Differences in loading capacity of diatoms (15-24%) and release time (6-15 days) were observed which is due to the presence of different functional groups on the surface. It was found that 2-carboxyethyl-phosphonic acid, 3-aminopropyltriethoxy silane and N-(3-(trimethoxysilyl) propyl) ethylene diamine render diatom surfaces hydrophilic, due to polar carboxyl functional group (COOH) and active amine species (NH and NH2) that favor drug adsorption; better encapsulation efficiency and prolonged release of drugs, over the hydrophobic surface created by 16-phosphono-hexadecanoic acid. This work demonstrates diatom porous silica as a promising drug carrier, with possibility to further improve their performances by tailoring their surface functionalities to achieve the required drug loading and release characteristics for different therapeutic conditions.
Keywords: Drug delivery; diatoms; diatomaceous earth; surface modifications; silanes; phosphonic acid; indomethacin
Rights: © The Author(s) 2012
RMID: 0020125354
DOI: 10.1177/0885328212441846
Grant ID:
Appears in Collections:Chemical Engineering publications

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.