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Numerous strategies exist to design a suitable bone graft made from polyurethane (PU) nanofibers. However, using PU nanofibers is impractical owing to their hydrophobicity. This work transforms the hydrophobicity of PU nanofibers using β‐cyclodextrin (β‐CD) and zinc oxide (ZnO) nanoparticles (NPs). Transmission and scanning electron microscopy (SEM) indicated the size of ~100 to 200 nm for ZnO NPs, and these NPs could finely harmonize inside nanofibers. The phenolphthalein absorbance test confirmed the inclusion of ZnO and β‐CD. Fourier transform infrared, X‐ray diffraction, and photoelectron spectroscopy showed that synthesized composites have intermolecular hydrogen interactions between the PU, β‐CD, and ZnO NPs. These embellishments improved the hydrophilicity from a contact angle of 60.2 ± 0.2° to 0°. The tensile strength of modified fibers increased from 2.16 ± 0.14 to 6.65 ± 6.0 MPa. The incorporation of ZnO NPs caused the mineralization of the nanofibers and the maximum number of hydroxyapatite NPs in the composite, which had the highest concentration of ZnO NPs. These nanofiber mats boosted the proliferation of Human Embryonic Kidney 293 T cells till 6 days of culture for the nanofiber with 5% β‐CD and 75 mg ZnO NPs combination. Cell fixation studies indicated the successful attachment of cells onto nanofibers. Consequently, our multifunctional scaffolds could be osteoproductive and osteoinductive biomaterials for future bone tissue engineering. [ABSTRACT FROM AUTHOR]

The hydrophobicity of polyurethane fibers is undesired for tissue engineering. In this work, fibers are fabricated by electrospinning and coated with silk fibroin (SF) for biocompatibility and biologically synthesized silver (Ag) nanoparticles (NPs) for antibacterial activity. The scanning electron microscopy reveals the undistorted morphology and the presence of NPs on fibers. The Fourier transform infrared and thermogravimetric analysis show the successful incorporation of SF and Ag NPs. The water contact angle drops from 101.26±0.2° in pristine to 3.1±0.3° in the hydrothermally treated fibers. The moisture regain from 1.87±0.3% to 6.7±0.4% is observed after 24 h. The mineralization shows the hydroxyapatite NPs in all composites. The large zone of inhibition is observed in the composite, with the Ag NPs equal to 11.5±0.04 mm for Staphylococcus aureus and 18.91±0.02 mm for Escherichia coli. The increased proliferation of HEK 293T cells for 6 days of culture on composite scaffolds compared to the pristine scaffolds is achieved. The cell attachment examinations show successful attachment of cells on fibers and nuclear staining analysis shows the highest proliferation in scaffolds with an intermediate concentration of Ag NPs (10%). This strategy presents a novel improvisation for as‐spun PU fibers that can fabricate wound‐healing biomaterials for tissue engineering. [ABSTRACT FROM AUTHOR]

There is an extensive possibility of improving characteristics of fibers used in hard tissue engineering, being hydrophobic and less osteoconductive, resulting in the dynamic growth of new tissues. The current work focuses on the fabrication of nanofibers incorporated with titanium dioxide (TiO2) ''as osteoconductive'' and silver (Ag) ''as self‐healing'' nanoparticles (NPs). The incorporation of AgNO3 by in situ method not only helped to impart the antibacterial activity but also changed the contact angle from 81 ± 03° in the case of pristine nanofibers to 74 ± 03°, 61 ± 03°, 50 ± 08°, and 39 ± 1.1°, in the composite scaffolds containing 0.01, 0.03, 0.05, and 0.07 M of Ag salts. The incubation in simulated body fluid at 37°C to induce mineralization on nanofiber scaffolds indicated Ca and P crystals' formation. The antibacterial activity showed significantly more toxicity toward E. coli (8.3 ± 0.9 mm) than S. aureus (1.2 ± 0.1 mm). Biocompatibility studies using MTT assay on the pre‐osteoblasts showed that both TiO2 and Ag NPs present in the nanofibers are non‐toxic to the bone‐like cells. However, results show that a higher concentration of Ag NPs (i.e., 0.07 M) is toxic to cells growing. Finally, all the results suggest that the nanofiber scaffolds have considerable scope for future bone tissue engineering materials. [ABSTRACT FROM AUTHOR]

In this study, polyurethane (PU) and cellulose acetate (CA) electrospun fibers encapsulating rosemary essential oil (REO) and adsorbed silver (Ag) nanoparticles (NPs) were fabricated. The biologically inspired materials were analyzed for physicochemical characteristics using scanning electron microscopy, X-ray diffractometer, Fourier transform infrared, thermal gravimetric analysis, X-ray photoelectron spectroscopy, water contact angle, and water uptake studies. Results confirmed the presence of CA and Ag NPs on the PU micro-nanofibers increased the hydrophilicity from 107.1 ± 0.36o to 26.35 ± 1.06o. The water absorption potential increased from 0.07 ± 0.04 for pristine PU fibers to 12.43 ± 0.49 % for fibers with 7 wt% of CA, REO, and Ag NPs. The diffractometer confirmed the 2θ of 38.01°, 44.13o, and 64.33o, corresponding to the diffraction planes of Ag on the fibers. The X-ray photoelectron spectroscopy confirmed microfibers interfacial chemical interaction and surface changes due to CA, REO, and Ag presence. The inhibition tests on Staphylococcus aureus and Escherichia coli indicated that composites are antibacterial in activity. Moreover, synergistic interactions of REO and Ag NPs resulted in superior antibacterial activity. The cell viability and attachment assay showed improved hydrophilicity of the fibers, which resulted in better attachment of cells to the micro-nanofibers, similar to the natural extracellular matrix in the human body. [ABSTRACT FROM AUTHOR]

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 β-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 μm, and that of ultrasonically adsorbed Ag NPs was 4.0 ± 1.7 μm. The hydrophilicity results showed that incorporation of β-cyclodextrin in mats led to the decrease in water angle, and the Ag NPs adsorbed mats measured 53.50 ± 0.1° and 55.18 ± 0.15° 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. [Display omitted] • Electrospun pristine PU fibers incorporated with β-cyclodextrin were prepared. • Silver nanoparticles (Ag NPs) were adsorbed for the necessary antibacterial activity by two methods, viz, ultrasonication and hydrothermal reaction. • Modification with β-CD and Ag NPs could provide better physico-chemical properties for PU fiber mats. • Diameter of the PU fibers incorporated with β-CD and ultrasonically adsorbed Ag NPs were lower as compared to the PU fibers incorporated with β-CD and hydrothermally adsorbed Ag NPs. • The comparative analysis of properties such as hydrophilicity, biodegradability, antibacterial activity, biocompatibility etc. was done among the different types of mats. • The best scaffold with reference to antibacterial activity, cell viability and cell attachment was the one having ultrasonically adsorbed Ag NPs. [ABSTRACT FROM AUTHOR]

Cellulose nanofibers, which are troublesome to spin into fibers, can be easily fabricated by post-regeneration of its acetate-derived threads. Cellulose is a natural polymer; it enjoys better biocompatibility, cellular mimicking, and hydrophilic properties than its proportionate analog. Herein, we regenerated acetate-free nanofibers by alkaline de-acetylation of as-spun nanofibers. The resultant cellulose nanofibers previously loaded with hydroxyapatite (HAp) were immobilized using silver (Ag) nanoparticles (NPs) by reduction of adsorbed Ag ions on using sodium borohydride. These amalgamated nanofibers were characterized for SEM, EDX, TEM, FTIR, and hydrophilicity tests revealing the existence of both HAp and Ag NPs in/on the nanofiber scaffolds. The de-acetylation of composite nanofibers resulted in spontaneous hydrophilicity. These nanofibers were cytocompatible, as resolved by MTT assay conducted on chicken embryo fibroblasts. The SEM of the samples after cell culture revealed that these composites allowed a proliferation of the fibroblasts over and within the nanofiber network, and increased concentration of HAp levitated the excessive of apatite formation as well as increased cell growth. The antimicrobial activity of these nanofibers was assessed on E. coli (BL21) and S. aureus , suggesting the potential of de-acetylated nanofibers to restrain bacterial growth. The degradation study for 10, 30, and 60 days indicated degradation of the fibers much is faster in enzymes as compared to degradation in PBS. The results certify that these nanofibers possess enormous potential for soft and hard tissue engineering besides their antimicrobial properties. • Multifunctional cellulose nanofiber can be prepared using least toxic solvents. • Cellulose acetate nanofibers can retain morphology using NaOH solution. • Significant decrease on fiber diameter can occur. • The mineralization can provide the physiological environment for adhesion, growth, and proliferation of fibroblasts. [ABSTRACT FROM AUTHOR]