Comparative study on silver nanoparticles adsorption by ultrasonication and hydrothermal approaches on 8-cyclodextrin incorporated polyurethane micro-nanofibers as multifunctional tissue engineering candidate

For an efficient tissue-engineered implant, it is mandatory to have appropriate fluid absorption and antibacterial properties. In this regard, polyurethane micro-nanofibers were modified by incorporating beta-cyclodextrin by electrospinning and then adsorbed using silver (Ag) nanoparticles (NPs). We selected the adsorption by ultrasonication and hydrothermal methods and compared results for hydrophilicity, biodegradation, biocompatibility, and antibacterial activity. Scanning electron microscopy confirmed fiber diameter in mats with hydrothermally adsorbed Ag NPs was 8.0 +/- 2.2 mu m, and that of ultrasonically adsorbed Ag NPs was 4.0 +/- 1.7 mu m. The hydrophilicity results showed that incorporation of beta-cyclodextrin in mats led to the decrease in water angle, and the Ag NPs adsorbed mats measured 53.50 +/- 0.1 degrees and 55.18 +/- 0.15 degrees at 1 min. The Ag NPs release by UV-visible spectroscopy indicated higher release in the case of ultrasonically adsorbed Ag NPs. Ultrasonically adsorbed Ag NPs showed higher antibacterial activity than hydrothermally against Staphylococcus aureus and Escherichia coli with 15 +/- 2 mm and 12 +/- 1 mm clear zones. The mouse fibroblasts showed a viability of >100 % in all mats, which determined that the fibers were biocompatible. The highest viability was seen in ultrasonically adsorbed Ag NP mats (262.76 +/- 11.24 %). The cell attachment studies showed well-spread cells, concluding with excellent biocompatibility. Overall, results indicate ultrasonic adsorption is a straightforward and better strategy than hydrothermal treatment.