Development of Specially Designed Nanoparticle-coated 3D-printed Gelatin Methacryloyl Patches for Potential Tissue Engineering Applications

Tympanic membrane (TM) perforation is a serious ear discomfort that can cause hearing loss and make the middle ear vulnerable to infections. In this study, a unique TM patch is designed to mimic the structure of the natural eardrum for tissue engineering of TM perforations. Gelatin methacryloyl (GelMA)-based TM patches are equipped with microneedles (MNs) to better adhere to the perforation site and developed using the digital light processing (DLP) based 3D printing technique. To impart biofunctionality to the 3D-printed patches, their surfaces are coated with gentamicin (GEN) loaded poly(vinyl alcohol) (PVA) nanoparticles (NPs) using the Electrohydrodynamic Atomization (EHDA) method. The physicochemical characteristics, drug release behaviour, antimicrobial properties and biocompatibility of GelMA, PVA NP-coated GelMA, and GEN@PVA NP-coated GelMA patches are investigated. Morphological analyses confirmed that 3D-printed GelMA patches are fabricated in desired sizes and geometries and successfully coated with NPs. In vitro antibacterial tests revealed that GEN@PVA NP-coated GelMA patches have antibacterial activities against Staphylococcus aureus and Escherichia coli. Moreover, in vitro cell culture studies indicated that all GelMA-based patches have no cytotoxic effect on L929 mouse fibroblast cells. Considering all, these specially designed biofunctional 3D-printed GelMA patches can be an effective therapeutic approach for repairing TM perforations.

This study aims to design a unique tympanic membrane (TM) patch model for tissue engineering of TM perforations. The edges of the patch are donated with microneedles (MNs) for improved attachment to the perforation site. Gelatin methacryloyl (GelMA)-based TM patches are fabricated using the digital light processing (DLP) based 3D printing technique. To enhance the biofunctionality of the 3D-printed GelMA patches, the patches are coated with gentamicin (GEN) loaded poly(vinyl alcohol) (PVA) nanoparticles (NPs) employing the Electrohydrodynamic Atomization (EHDA) technique. These specially designed biofunctional patches can serve as a promising treatment method for repairing TM perforations. image