Preparation and characterization of polycaprolactone/diclofenac sodium and poly(vinyl alcohol)/tetracycline hydrochloride fiber mats and their release of the model drugs

In the present contribution, electrospinning was used to fabricate ultrafine fiber mats from neat polycaprolactone (PCL) and poly(vinyl alcohol) (PVA) solutions as well as PVA/sodium alginate (SA) blend solutions and the PCL and PVA solutions that contained diclofenac sodium (DS) and tetracycline hydrochloride (TH) as the model drugs. The effects of solution and process parameters (i.e., solution concentration, applied electrical potential, and collection distance) on morphological appearance and size of the as-spun PCL, PVA, and PVA/SA fibers were investigated. Generally, the average fiber diameter increased with increasing solution concentration and decreased with increasing both the applied electrical potential and the collection distance. Incorporation of the model drugs caused the resulting as-spun fibers to be larger in their diameters. The cumulative release of the model drugs from drug-loaded as-spun PCL and PVA fiber mats increased monotonically with increasing immersion time and became practically constant at long immersion times. Finally, a thin layer of PVA/SA fibers that were coated on TH-loaded PVA fiber mats caused the total amount of the drug released to decrease appreciably.