Characterization and biological evaluation of new PLGA/fibrin/lignin biocomposite electrospun scaffolds

Abstract

In this study, we produced electrospun scaffolds from 10 pure PLGA solution, and 10 polyblend solutions of PLGA/Fibrin, PLGA/Lignin, and PLGA/Fibrin/Lignin with proportions of 9:1, 8:2, 7:3, 7:2:1, 6:2:2, and 5:2:3 and characterized them physiochemically and biologically. FTIR and EDX results verified the chemical composition of the fibers. All scaffolds exhibited homogenous nanostructures with fiber diameters ranging from 0.1 to 2.5 & mu;m and the highest average fiber diameter belonged to PLGA/Lignin fibers. Increasing the lignin proportion led to a decrease in fibers diameter and a change in color to brown. Fibrin improved the hydrophobicity of the scaffolds, and the incorporation of fibrin, lignin, or fibrin/lignin improved the absorption capacity of the scaffolds (up to 91.7). From day 45 onwards, fibrin-containing scaffolds started to degrade much faster. By day 90, PLGA/20Fibrin/30Lignin showed the highest degradation ratio of 82, while PLGA/10Lignin showed the lowest at 51.4. All scaffolds exhibited high porosity percentage (over 78), with porosity enhanced by increasing fibrin and decreasing lignin. The pure PLGA scaffold and PLGA/10Lignin showed the highest stiffness and tensile strength, respectively. The addition of natural components gradually decreased the scaffolds' tensile strength and fracture strain. MTT results showed higher absorbance reading at 490 nm for PLGA, PLGA/10Fibrin, and all three PLGA/Lignin scaffolds from day 3 to day 7. On day 7, PLGA/10Fibrin exhibited the highest cell viability, followed by PLGA/10Lignin and PLGA/20Fibrin/10Lignin. SEM micrographs revealed the presence of h-ADSCs with spindle-like morphologies, attached and proliferated well on all scaffolds. PLGA/10Fibrin, PLGA/10Lignin, and PLGA/20Fibrin/10Lignin were selected as the preferred options from each set of scaffolds. Among them, PLGA/20Fibrin/10Lignin exhibited superior physical features and actively enhanced the biological responses of the cells due to its physio-mechanical signals and the advanced features of lignin, making it suitable for tissue engineering, wound dressing, drug delivery, and other biomedical applications.