title: Alginate-based hybrid aerogel microparticles for mucosal drug delivery.
abstract: The application of biopolymer aerogels as drug delivery systems (DDS) has gained increased interest during the last decade since these structures have large surface area and accessible pores allowing for high drug loadings. Being biocompatible, biodegradable and presenting low toxicity, polysaccharide-based aerogels are an attractive carrier to be applied in pharmaceutical industry. Moreover, some polysaccharides (e.g. alginate and chitosan) present mucoadhesive properties, an important feature for mucosal drug delivery. This feature allows to extend the contact of DDS with biological membranes, thereby increasing the absorption of drugs through the mucosa. Alginate-based hybrid aerogels in the form of microparticles (<50μm) were investigated in this work as carriers for mucosal administration of drugs. Low methoxyl pectin and κ-carrageenan were co-gelled with alginate and further dried with supercritical CO2 (sc-CO2). Spherical mesoporous aerogel microparticles were obtained for alginate, hybrid alginate/pectin and alginate/κ-carrageenan aerogels, presenting high specific surface area (370-548m(2)g(-1)) and mucoadhesive properties. The microparticles were loaded with ketoprofen via adsorption from its solution in sc-CO2, and with quercetin via supercritical anti-solvent precipitation. Loading of ketoprofen was in the range between 17 and 22wt% whereas quercetin demonstrated loadings of 3.1-5.4wt%. Both the drugs were present in amorphous state. Loading procedure allowed the preservation of antioxidant activity of quercetin. Release of both drugs from alginate/κ-carrageenan aerogel was slightly faster compared to alginate/pectin. The results indicate that alginate-based aerogel microparticles can be viewed as promising matrices for mucosal drug delivery applications.
authors.affiliation: Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. Da República, 2780-157 Oeiras, Portugal; iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal; Escuela de Ingenierías Industriales, Universidad de Valladolid, C/Dr. Mergelina s/n, 47011 Valladolid, Spain.
authors.forename: V S S
authors.initials: VS
authors.lastname: Gonçalves
authors.affiliation: Institute of Thermal Separation Processes, Hamburg University of Technology, Eißendorferstr. 38, 21073 Hamburg, Germany. Electronic address: pavel.gurikov@tuhh.de.
authors.forename: P
authors.initials: P
authors.lastname: Gurikov
authors.affiliation: Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. Da República, 2780-157 Oeiras, Portugal; iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal.
authors.forename: J
authors.initials: J
authors.lastname: Poejo
authors.affiliation: Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. Da República, 2780-157 Oeiras, Portugal; iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal.
authors.forename: A A
authors.initials: AA
authors.lastname: Matias
authors.affiliation: Institute of Solids Process Engineering and Particle Technology, Hamburg University of Technology, Denickestr. 15, 21073 Hamburg, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Heinrich
authors.affiliation: Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. Da República, 2780-157 Oeiras, Portugal; iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal.
authors.forename: C M M
authors.initials: CM
authors.lastname: Duarte
authors.affiliation: Institute of Thermal Separation Processes, Hamburg University of Technology, Eißendorferstr. 38, 21073 Hamburg, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Smirnova
mesh_terms: D000464:Alginates / Q000737:chemistry*; D018938:Caco-2 Cells; D002152:Calorimetry, Differential Scanning; D004337:Drug Carriers; D005782:Gels; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006801:Humans; D008855:Microscopy, Electron, Scanning; D009092:Mucous Membrane
chemical_list: D000464:Alginates; D004337:Drug Carriers; D005782:Gels; D006603:Hexuronic Acids; D020723:Glucuronic Acid
keywords: Alginate; Carrageenan; Hybrid aerogels; Microparticles; Pectin; Supercritical fluid technology