title: Porous calcium phosphate-poly (lactic-co-glycolic) acid composite bone cement: A viable tunable drug delivery system.
abstract: Calcium phosphate based cements (CPCs) are frequently used as bone void fillers for non-load bearing segmental bone defects due to their clinically relevant handling characteristics and ability to promote natural bone growth. Macroporous CPC scaffolds with interconnected pores are preferred for their ability to degrade faster and enable accelerated bone regeneration. Herein, a composite CPC scaffold is developed using newly developed resorbable calcium phosphate cement (ReCaPP) formulation containing degradable microspheres of bio-compatible poly (lactic-co-glycolic acid) (PLGA) serving as porogen. The present study is aimed at characterizing the effect of in-vitro degradation of PLGA microspheres on the physical, chemical and structural characteristics of the composite cements. The porosity measurements results reveal the formation of highly interconnected macroporous scaffolds after degradation of PLGA microspheres. The in-vitro characterizations also suggest that the degradation by products of PLGA reduces the pH of the local environment thereby increasing the dissolution rate of the cement. In addition, the in-vitro vancomycin release from the composite CPC scaffold suggests that the drug association with the composite scaffolds can be tuned to achieve control release kinetics. Further, the study demonstrates control release lasting for longer than 10weeks from the composite cements in which vancomycin is encapsulated in PLGA microspheres.
authors.affiliation: Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261, USA.
authors.forename: Abhijit
authors.initials: A
authors.lastname: Roy
authors.affiliation: Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261, USA.
authors.forename: Siddharth
authors.initials: S
authors.lastname: Jhunjhunwala
authors.affiliation: Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261, USA.
authors.forename: Emily
authors.initials: E
authors.lastname: Bayer
authors.affiliation: Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA.
authors.forename: Morgan
authors.initials: M
authors.lastname: Fedorchak
authors.affiliation: Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261, USA; Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA.
authors.forename: Steve R
authors.initials: SR
authors.lastname: Little
authors.affiliation: Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261, USA; Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA; Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, PA 15261, USA; Oral Biology, Center for Craniofacial Regeneration, University of Pittsburgh, Pittsburgh, PA 15260, USA. Electronic address: pkumta@pitt.edu.
authors.forename: Prashant N
authors.initials: PN
authors.lastname: Kumta
mesh_terms: D001843:Bone Cements / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D002130:Calcium Phosphates / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D016503:Drug Delivery Systems / Q000379:methods*; D019344:Lactic Acid / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D011100:Polyglycolic Acid / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D016062:Porosity; D014640:Vancomycin / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology
chemical_list: D001843:Bone Cements; D002130:Calcium Phosphates; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D014640:Vancomycin; C020243:calcium phosphate
keywords: Calcium phosphate cement; Controlled release; Drug delivery; PLGA; Porogen