Method for measuring mucoadhesion of ophthalmica considering regulatory aspects

In this technical note we present an easy to use method for determining mucoadhesion for ophthalmica, easily applicable in a regulated setting. The determined value of mucoadhesion is a combination value of adhesion and cohesion force, as both are relevant to the retention of a formulation and thus its bioavailability. The method is specifically designed to test two formulations against each other to gain information on bioequivalence. We tested 14 different commercially available ocular formulations as function of their content of hyaluronic acid - a known mucoadhesive. We could find a trend of higher mucoadhesion for formulations with higher contents of hyaluronic acid in control and sample, though some samples deviate from the expected values. Furthermore, we provide background information on the qualification of the device and the method validation according to guidelines.