title: Relationships between mechanical properties and drug release from electrospun fibers of PCL and PLGA blends.
abstract: Electrospun nanofibers have the potential to achieve high drug loading and the ability to sustain drug release. Mechanical properties of the drug-incorporated fibers suggest the importance of drug-polymer interactions. In this study, we investigated the mechanical properties of electrospun polycaprolactone (PCL) and poly (D,L-lactic-co-glycolic) acid (PLGA) fibers at various blend ratios in the presence and absence of a small molecule hydrophilic drug, tenofovir (TFV). Young׳s modulus of the blend fibers showed dependence on PLGA content and the addition of the drug. At a PCL/PLGA (20/80) composition, Young׳s modulus and tensile strength were independent of drug loading up to 40wt% due to offsetting effects from drug-polymer interactions. In vitro drug release studies suggested that release of TFV significantly decreased fiber mechanical properties. In addition, mechanically stretched fibers displayed a faster release rate as compared to the non-stretched fibers. Finally, drug partition in the blend fibers was estimated using a mechanical model and then experimentally confirmed with a composite of individually stacked fiber meshes. This work provides scientific understanding on the dependence of drug release and drug loading on the mechanical properties of drug-eluting fibers.
authors.affiliation: Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA 98195-5061, USA.
authors.forename: Shih-Feng
authors.initials: SF
authors.lastname: Chou
authors.affiliation: Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA 98195-5061, USA. Electronic address: woodrow@uw.edu.
authors.forename: Kim A
authors.initials: KA
authors.lastname: Woodrow
mesh_terms: D065546:Drug Liberation; D055119:Elastic Modulus; D019344:Lactic Acid / Q000032:analysis*; D057139:Nanofibers / Q000032:analysis*; D011100:Polyglycolic Acid / Q000032:analysis*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D013718:Tensile Strength
chemical_list: D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid
keywords: Drug loading; Drug partition; Drug release; Drug–polymer interaction; Electrospun fibers; Mechanical properties