title: Novel PCL-based honeycomb scaffolds as drug delivery systems for rhBMP-2.
abstract: This study investigated a novel drug delivery system (DDS), consisting of polycaprolactone (PCL) or polycaprolactone 20% tricalcium phosphate (PCL-TCP) biodegradable scaffolds, fibrin Tisseel sealant and recombinant bone morphogenetic protein-2 (rhBMP-2) for bone regeneration. PCL and PCL-TCP-fibrin composites displayed a loading efficiency of 70% and 43%, respectively. Fluorescence and scanning electron microscopy revealed sparse clumps of rhBMP-2 particles, non-uniformly distributed on the rods' surface of PCL-fibrin composites. In contrast, individual rhBMP-2 particles were evident and uniformly distributed on the rods' surface of the PCL-TCP-fibrin composites. PCL-fibrin composites loaded with 10 and 20 microg/ml rhBMP-2 demonstrated a triphasic release profile as quantified by an enzyme-linked immunosorbent assay (ELISA). This consisted of burst releases at 2 h, and days 7 and 16. A biphasic release profile was observed for PCL-TCP-fibrin composites loaded with 10 microg/ml rhBMP-2, consisting of burst releases at 2 h and day 14. PCL-TCP-fibrin composites loaded with 20 microg/ml rhBMP-2 showed a tri-phasic release profile, consisting of burst releases at 2 h, and days 10 and 21. We conclude that the addition of TCP caused a delay in rhBMP-2 release. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and alkaline phosphatase assay verified the stability and bioactivity of eluted rhBMP-2 at all time points.
authors.affiliation: Faculty of Dentistry, National University of Singapore, Singapore. g0201957@nus.edu.sg
authors.forename: B
authors.initials: B
authors.lastname: Rai
authors.forename: S H
authors.initials: SH
authors.lastname: Teoh
authors.forename: D W
authors.initials: DW
authors.lastname: Hutmacher
authors.forename: T
authors.initials: T
authors.lastname: Cao
authors.forename: K H
authors.initials: KH
authors.lastname: Ho
mesh_terms: D001826:Body Fluids / Q000737:chemistry*; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage* / Q000737:chemistry; D018786:Bone Substitutes / Q000008:administration & dosage*; D002130:Calcium Phosphates / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000008:administration & dosage / Q000737:chemistry; D004058:Diffusion; D004338:Drug Combinations; D004353:Drug Evaluation, Preclinical; D004343:Drug Implants / Q000008:administration & dosage* / Q000737:chemistry; D015718:Fibrin Tissue Adhesive / Q000008:administration & dosage* / Q000737:chemistry; D008422:Materials Testing; D011091:Polyesters / Q000737:chemistry*; D016212:Transforming Growth Factor beta / Q000008:administration & dosage* / Q000737:chemistry
chemical_list: D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D018786:Bone Substitutes; D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; D004338:Drug Combinations; D004343:Drug Implants; D015718:Fibrin Tissue Adhesive; D011091:Polyesters; D016212:Transforming Growth Factor beta; C016240:polycaprolactone; C018392:tricalcium phosphate