title: Towards biomimetic scaffolds: anhydrous scaffold fabrication from biodegradable amine-reactive diblock copolymers.
abstract: The development of biomimetic materials and their processing into three-dimensional cell carrying scaffolds is one promising tissue engineering strategy to improve cell adhesion, growth and differentiation on polymeric constructs developing mature and viable tissue. This study was concerned with the fabrication of scaffolds made from amine-reactive diblock copolymers, N-succinimidyl tartrate monoamine poly(ethylene glycol)-block-poly(D,L-lactic acid), which are able to suppress unspecific protein adsorption and to covalently bind proteins or peptides. An appropriate technique for their processing had to be both anhydrous, to avoid hydrolysis of the active ester, and suitable for the generation of interconnected porous structures. Attempts to fabricate scaffolds utilizing hard paraffin microparticles as hexane-extractable porogens failed. Consequently, a technique was developed involving lipid microparticles, which served as biocompatible porogens on which the scaffold forming polymer was precipitated in the porogen extraction media (n-hexane). Porogen melting during the extraction and polymer precipitation step led to an interconnected network of pores. Suitable lipid mixtures and their melting points, extraction conditions (temperature and time) and a low-toxic polymer solvent system were determined for their use in processing diblock copolymers of different molecular weights (22 and 42 kDa) into highly porous off-the-shelf cell carriers ready for easy surface modification towards biomimetic scaffolds. Insulin was employed to demonstrate the principal of instant protein coupling to a prefabricated scaffold.
authors.affiliation: Department of Pharmaceutical Technology, University of Regensburg, Universitaetsstrasse 31, 93040 Regensburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Hacker
authors.forename: Jörg
authors.initials: J
authors.lastname: Tessmar
authors.forename: Markus
authors.initials: M
authors.lastname: Neubauer
authors.forename: Andrea
authors.initials: A
authors.lastname: Blaimer
authors.forename: Torsten
authors.initials: T
authors.lastname: Blunk
authors.forename: Achim
authors.initials: A
authors.lastname: Göpferich
authors.forename: Michaela B
authors.initials: MB
authors.lastname: Schulz
mesh_terms: D001672:Biocompatible Materials; D040761:Biomimetic Materials / Q000737:chemistry*; D001704:Biopolymers / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D002455:Cell Division; D002470:Cell Survival; D008855:Microscopy, Electron, Scanning; D010232:Paraffin; D011092:Polyethylene Glycols / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D001672:Biocompatible Materials; D001704:Biopolymers; D011092:Polyethylene Glycols; D010232:Paraffin