title: In vitro and in vivo investigation of the potential of amorphous microporous silica as a protein delivery vehicle.
abstract: Delivering growth factors (GFs) at bone/implant interface needs to be optimized to achieve faster osseointegration. Amorphous microporous silica (AMS) has a potential to be used as a carrier and delivery platform for GFs. In this work, adsorption (loading) and release (delivery) mechanism of a model protein, bovine serum albumin (BSA), from AMS was investigated in vitro as well as in vivo. In general, strong BSA adsorption to AMS was observed. The interaction was stronger at lower pH owing to favorable electrostatic interaction. In vitro evaluation of BSA release revealed a peculiar release profile, involving a burst release followed by a 6 h period without appreciable BSA release and a further slower release later. Experimental data supporting this observation are discussed. Apart from understanding protein/biomaterial (BSA/AMS) interaction, determination of in vivo protein release is an essential aspect of the evaluation of a protein delivery system. In this regard micropositron emission tomography (μ -PET) was used in an exploratory experiment to determine in vivo BSA release profile from AMS. Results suggest stronger in vivo retention of BSA when adsorbed on AMS. This study highlights the possible use of AMS as a controlled protein delivery platform which may facilitate osseointegration.
authors.affiliation: Department of Prosthetic Dentistry, BIOMAT Research Group, KU Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium.
authors.forename: Amol
authors.initials: A
authors.lastname: Chaudhari
authors.forename: Lieve
authors.initials: L
authors.lastname: Vanmellaert
authors.forename: Matthias
authors.initials: M
authors.lastname: Bauwens
authors.forename: Peter
authors.initials: P
authors.lastname: Vermaelen
authors.forename: Christophe M
authors.initials: CM
authors.lastname: Deroose
authors.forename: Ignace
authors.initials: I
authors.lastname: Naert
authors.forename: Marcio Vivan
authors.initials: MV
authors.lastname: Cardoso
authors.forename: Johan A
authors.initials: JA
authors.lastname: Martens
authors.forename: Joke
authors.initials: J
authors.lastname: Duyck
mesh_terms: D000327:Adsorption; D000818:Animals; D002214:Capsules / Q000008:administration & dosage / Q000737:chemistry*; D003692:Delayed-Action Preparations / Q000008:administration & dosage* / Q000737:chemistry*; D004058:Diffusion; D005240:Feasibility Studies; D016062:Porosity; D011817:Rabbits; D012710:Serum Albumin, Bovine / Q000008:administration & dosage* / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D002214:Capsules; D003692:Delayed-Action Preparations; D012710:Serum Albumin, Bovine; D012822:Silicon Dioxide