Structural and Viability Assessment of Bovine Corneas Preserved at an Accessible Low-Temperature (−20 °C) for Eye Irritation Models

<i>In vitro</i> ocular irritation testing requires the use of freshly excised bovine corneas, which limits broader adoption in laboratories with restricted access to slaughterhouse material. This study investigated a practical and accessible low-temperature preservation strategy focused on maintaining structural and cellular integrity. Bovine corneas were stored at -20 or -80 °C using two commonly available cryoprotective agents: dimethyl sulfoxide (DMSO) and ethylene glycol (EG). Preservation outcomes were assessed through corneal transparency, histological architecture, and endothelial viability. Among the tested conditions, storage at -20 °C with 10% DMSO provided the most consistent preservation of structural morphology and transparency. This protocol provides a cost-effective foundation for extending the usability of excised corneas and supports future efforts to expand the accessibility of <i>in vitro</i> eye irritation models in laboratories with limited infrastructure.