title: Polymer powder processing of cryomilled polycaprolactone for solvent-free generation of homogeneous bioactive tissue engineering scaffolds.
abstract: Synthetic polymers used in tissue engineering require functionalization with bioactive molecules to elicit specific physiological reactions. These additives must be homogeneously dispersed in order to achieve enhanced composite mechanical performance and uniform cellular response. This work demonstrates the use of a solvent-free powder processing technique to form osteoinductive scaffolds from cryomilled polycaprolactone (PCL) and tricalcium phosphate (TCP). Cryomilling is performed to achieve micrometer-sized distribution of PCL and reduce melt viscosity, thus improving TCP distribution and improving structural integrity. A breakthrough is achieved in the successful fabrication of 70 weight percentage of TCP into a continuous film structure. Following compaction and melting, PCL/TCP composite scaffolds are found to display uniform distribution of TCP throughout the PCL matrix regardless of composition. Homogeneous spatial distribution is also achieved in fabricated 3D scaffolds. When seeded onto powder-processed PCL/TCP films, mesenchymal stem cells are found to undergo robust and uniform osteogenic differentiation, indicating the potential application of this approach to biofunctionalize scaffolds for tissue engineering applications.
authors.affiliation: Division of Bioengineering, School of Chemical and Biomedical Engineering, 70 Nanyang Drive, Singapore, 637457, Singapore.
authors.forename: Jing
authors.initials: J
authors.lastname: Lim
authors.forename: Mark Seow Khoon
authors.initials: MS
authors.lastname: Chong
authors.forename: Jerry Kok Yen
authors.initials: JK
authors.lastname: Chan
authors.forename: Swee-Hin
authors.initials: SH
authors.lastname: Teoh
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D002130:Calcium Phosphates / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D005615:Freezing; D006801:Humans; D008422:Materials Testing; D059630:Mesenchymal Stem Cells / Q000187:drug effects / Q000502:physiology; D010012:Osteogenesis / Q000187:drug effects; D010316:Particle Size; D011091:Polyesters / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D011208:Powders / Q000138:chemical synthesis / Q000737:chemistry; D012997:Solvents; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D002130:Calcium Phosphates; D011091:Polyesters; D011108:Polymers; D011208:Powders; D012997:Solvents; C016240:polycaprolactone; C018392:tricalcium phosphate
keywords: cryomilling; homogeneous bioactive composites; solvent-free; tissue engineering