A Design of Experiment (DOE) approach to correlate PLA-PCL electrospun fibers diameter and mechanical properties for soft tissue regeneration purposes

Many parameters are involved in electrospun fibers development; depending on application field fibers have to exhibit defined properties regarding fibers diameter and mechanical properties. A valid method to study and predict electrospinning parameters interactions is Design of Experiment (DOE) approach. DOE method takes into account the interaction between various selected parameters using a linear regression and analysis of variance (ANOVA) mathematical models. Moreover, from DOE design is possible to achieve a test model prediction obtaining equations useful to calculate in advance values of desired output. In this work poly-L-lactide-poly-ε-caprolactone (PLA-PCL) 70:30 ratio electrospun fibers were selected as model to obtain a DOE design considering as independent parameters: polymeric solution concentration (w/v%), needle (gauge) and spinning time (min). As design output or dependent variables were selected fibers diameter (μm) and elongation %. To confirm validity of DOE, predictive equations obtained from model were used to calculate fibers diameter and elongation % and compared with experimental results obtained for PLA-PCL 20%w/v electrospun matrix obtained using 25G needle and electrospun for 20 min. Results calculated from predictive model (Fibers diameter:1.101 μm; Elongation %: 111.96%) were experimentally confirmed (Fibers diameter: 1.05 ± 0.26 μm; Elongation %: 143 ± 32.9%).