Physical and mechanical properties of ocular thin films: a systematic review and meta-analysis

The ocular thin film presents a potential solution for addressing challenges to ocular drug delivery. In this review, we summarise the findings of a comprehensive review analysing 336 formulations from 68 studies. We investigated the physical and mechanical properties of ocular thin films, categorised into natural polymer-based, synthetic polymer-based, and combined polymer films. The results showed that the type of polymers used impacted mucoadhesion force, moisture absorption:moisture loss ratio, pH, swelling index, and elongation percentage. Significant relationships were found between these properties within each subgroup. The results also highlighted the influence of plasticisers on elongation percentage, mucoadhesion force, swelling index, and moisture absorption:moisture loss ratio. These findings have implications for designing and optimising ocular drug formulations and selecting appropriate plasticisers to achieve formulations with the desired properties.