Tympanic membrane (TM) perforations, primarily induced by middle ear infections, the introduction of foreign objects into the ear, and acoustic trauma, lead to hearing abnormalities and ear infections. We describe the design and fabrication of a novel composite patch containing photocrosslinkable gelatin methacryloyl (GelMA) and keratin methacryloyl (KerMA) hydrogels. GelMA-KerMA patches containing conical microneedles in their design were developed using the digital light processing (DLP) 3D printing approach. Following this, the patches were biofunctionalized by applying a coaxial coating with PVA nanoparticles loaded with gentamicin (GEN) and fibroblast growth factor (FGF-2) with the Electrohydrodynamic Atomization (EHDA) method. The developed nanoparticle-coated 3D-printed patches were evaluated in terms of their chemical, morphological, mechanical, swelling, and degradation behavior. In addition, the GEN and FGF-2 release profiles, antimicrobial properties, and biocompatibility of the patches were examined in vitro. The morphological assessment verified the successful fabrication and nanoparticle coating of the 3D-printed GelMA-KerMA patches. The outcomes of antibacterial tests demonstrated that GEN@PVA/GelMA-KerMA patches exhibited substantial antibacterial efficacy against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Furthermore, cell culture studies revealed that GelMA-KerMA patches were biocompatible with human adipose-derived mesenchymal stem cells (hADMSC) and supported cell attachment and proliferation without any cytotoxicity. These findings indicated that biofunctional 3D-printed GelMA-KerMA patches have the potential to be a promising therapeutic approach for addressing TM perforations.

We report the statistical parameters associated with the dynamic characteristics of a calcium microelectrode. The electrochemical behavior of the obtained microsensor was assessed against the main interferents.

Hybrid nanofibrous mats comprising distinct hydrophilic and hydrophobic fiber populations were fabricated by simultaneous dual-nozzle co-electrospinning for potential wound-dressing applications. Four formulations—polyvinyl alcohol (PVA)–polycaprolactone (PCL), PVA/Chitosan (CS)–PCL, PVA-PCL/Tea Tree Oil (TTO), and PVA/CS-PCL/TTO—were systematically evaluated in terms of their morphological, physicochemical, mechanical, release, and in vitro cellular properties. All formulations exhibited continuous, bead-free fiber morphologies. FTIR and DSC analyses indicated the physical incorporation of CS and TTO and composition-dependent changes in polymer-chain organization. TTO incorporation improved surface wettability, decreasing the water contact angle to 46.69 ± 2.80° and 57.05 ± 1.40° in the CS-free and CS-containing formulations, respectively. The PVA/CS-PCL/TTO mat exhibited the highest tensile strength (19.17 ± 3.06 MPa) and strain at break (10.82 ± 1.81%). Cumulative TTO release reached 97.63–99.75% within 8 h. MTT analysis showed favorable HDF metabolic activity, with the highest response observed for PVA/CS-PCL/TTO on day 7. Overall, the results support the further investigation of these hybrid nanofibrous mats as potential wound-dressing platforms.

Tendons are highly elastic connective tissues that transfer mechanical loads from muscle to bone, and their healing is often slow and incomplete because of limited vascularization. Tissue engineering approaches are therefore emerging as promising alternatives to support tendon repair. In this study, polylactic acid (PLA)-based nanofibers containing hyaluronic acid (HA) and collagen (COL), intrinsic components of the extracellular matrix, were fabricated by blend and coaxial electrospinning. Matrices of identical overall composition were produced by both configurations, so that the contribution of nanofiber architecture could be isolated from that of chemical composition; the coaxial nanofibers comprised a load-bearing PLA/COL core and a PLA/HA shell, reproducing the collagen-rich tendon proper and the hyaluronic acid-rich gliding surface of native tendon. Mean fiber diameters ranged from 319 ± 82 nm for neat PLA to 854 ± 220 nm for the coaxial nanofibers, approximately twice that of the compositionally identical blend nanofibers (454 ± 110 nm). Tensile strength increased from 2.108 MPa for neat PLA to 4.94 MPa for PLA/COL, and the coaxial nanofibers retained a comparable value (4.651 MPa, p > 0.05) despite the incorporation of HA. In human mesenchymal stem cells, viability was maintained or increased over 7 days on the coaxial scaffolds but declined markedly on the blend scaffolds, indicating that the core–shell architecture is more favorable for tendon tissue regeneration.