Fuzzy VIKOR Optimization for Designing High Performance Hydroxyapatite/Polycaprolactone Scaffolds for Hard Tissue Engineering

Electrospinning (ES) is a process affected by different factors including solutions, apparatus, and environmental parameters. Selecting ES parameters having effects on final scaffold properties is a multi-criteria decision-making problem. The use of statistical methods for multi-criteria decision-making can save time, energy and cost of the process and improve the efficiency of the final product. So in this study, the fuzzy VIKOR method with Shannon entropy weighting method was used for optimizing electrospun scaffold for bone tissue healing. For this, in the first step by trial and error, the percentage of polycaprolactone (PCL) in solution was selected. Then composite scaffolds were prepared with different hydroxyapatite (HA) concentrations and ES parameters (flow rate, ES distance, and the voltage). ES parameters, as well as HA concentration affected the studied characteristics of scaffolds. The obtained data were used for deploying weights of seven criteria based on Shannon entropy concept in fuzzy method optimization. Fiber diameter and distribution, surface and volume porosity, fiber alignment, surface roughness, and stable ES process were the 7 criteria considered in this study and 40 electrospun scaffolds were ranked with the fuzzy method by these criteria, then best-ranked samples redesigned. The redesigned samples were studied with SEM, AFM, TGA, Raman spectroscopy, water contact angle, tensile test, MTT assay, live/dead cells, and ALP activity tests. The diameter of the redesigned optimized scaffolds was obtained between 204 and 13 nm; and the surface and volume porosity were 67%-91% and 65%-86%, respectively. No toxicity was found and scaffolds had a positive effect on cell growth.