Relationships Between Mechanical Properties And Drug Release From Electrospun Fibers Of PCL And PLGA Blends
Authors: Shih-Feng Chou, Kim A. Woodrow
Abstract:
Electrospun nanofibers offer great potential for achieving high drug loading and sustained drug release. The mechanical properties of these drug-incorporated fibers underscore the significance of interactions between the drug and polymer. In this study, we examined the mechanical properties of electrospun fibers composed of polycaprolactone (PCL) and poly (D,L-lactic-co-glycolic) acid (PLGA) blends at different ratios, both with and without the hydrophilic drug tenofovir (TFV). The Young's modulus of the blended fibers exhibited dependence on the PLGA content and the presence of the drug. Notably, at a PCL/PLGA ratio of 20/80, the Young's modulus and tensile strength remained unaffected by drug loading up to 40 wt% due to compensatory effects arising from drug-polymer interactions. In vitro studies revealed that the release of TFV significantly impacted the mechanical properties of the fibers. Furthermore, mechanically stretched fibers exhibited a faster release rate compared to non-stretched fibers. Lastly, we estimated the drug partition within the blended fibers using a mechanical model and validated the results through experimental confirmation using a composite of individually stacked fiber meshes. This study contributes to our scientific understanding of how the mechanical properties of drug-eluting fibers influence drug release and loading.
Keywords
Electrospun fibers; Mechanical properties; Drug loading; Drug release; Drug–polymer interaction; Drug partition
Citation: Shih-Feng Chou, Kim A. Woodrow Relationships Between Mechanical Properties And Drug Release From Electrospun Fibers Of PCL And PLGA Blends http://dx.doi.org/10.1016/j.jmbbm.2016.09.004
Received: 8 July 2016, Revised: 1 September 2016, Accepted: 4 September 2016, Available online: 9 September 2016
Copyright: © 2016 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by/4.0/).
Conclusions
In summary, we report correlations between mechanical properties and drug release rates of electrospun blend fibers. Our results showed that incorporating TFV into PCL/PLGA fibers significantly modified the mechanical properties from blank fibers, suggesting a high level of drug-polymer interactions. TFV release decreased mechanical properties significantly at early time points. Pre-stretched PCL/PLGA blend fibers to failure showed higher release rates as compared to the non-stretched samples. Drug partitioning in PCL/PLGA fibers was evaluated using a mechanical model, and experimental data using stack fiber configurations confirmed that 80% of the TFV is in the PCL phase and 20% of TFV is in the PLGA phase. Our study contributes to scientific understanding of mechanical performance of drug-eluting fibers.
Acknowledgments
This work is supported by a grant from the US National Institutes of Health (AI112002) and a grant from the Bill and Melinda Gates Foundation (1067729) awarded to K.A.W. We thank D. Carson for critical discussions and review of the manuscript.
