Date of Thesis

Spring 2021


The effect of fiber diameter size on the controlled release of small molecule model drugs from dual electrospun polymeric nanofiber mats was investigated by fabricating poly(lactide-co-glycolide) (PLGA) electrospun nanofibers from polymeric solutions that incorporated rhodamine B (RhB) and Rhodamine 800 (Rh800) as model drugs. Different ratios of dimethylformamide (DMF) and Dichloromethane (DCM) in the electrospinning polymeric solution were used to produce varying diameters of the PLGA nanofibers, and drug diffusion was tested in vitro. PLGA shrinks under in vitro conditioning due to the plasticizing effects of water, so samples were annealed before testing. The resulting dual electrospun fiber mat consisted of ~250 nm PLGA fibers with Rh800 and ~450 nm PLGA fibers with RhB. The drug release profiles of rhodamine B from the dual electrospun PLGA fiber mat indicated a two phase burst release separated by a lag phase. The drug release profile of Rh800 from the dual electrospun PLGA fiber mat showed a lag phase over the first week and then a burst phase at a relatively higher rate than of the second burst phase of RhB. The first burst phase of RhB was attributed to the relatively solubility of RhB in DMF compared to DCM, where RhB is less solubility in DMF and thus was not uniformly distributed throughout the nanofibers. The second burst phase and lag phase was attributed to the autocatalyzed bulk degradation of PLGA.


electrospinning, nanofibers, PLGA, Drug Delivery

Access Type

Honors Thesis (Bucknell Access Only)

Degree Type

Bachelor of Science in Chemical Engineering


Chemical Engineering

Minor, Emphasis, or Concentration

Art History

First Advisor

Patrick Mather

Second Advisor

Ryan C. Snyder