Mucoadhesion and Mechanical Assessment of Oral Films.

Aligned with efforts to overcome shortcomings of conventional oral dosage forms, mucoadhesive oral thin films have been the focus of drug development. Transmucosal drug delivery through oral cavity is a popular alternative to deliver many drugs due to several advantages over conventional oral delivery including greater bioavailability due to bypassing the first-pass effect and avoiding enzymatic or acid-related degradation in the gastrointestinal tract, faster onset of action, and better patient compliance particularly in geriatric and pediatric patients. Furthermore, among solid transmucosal delivery platforms, buccal and sublingual strips or patches are more attractive due to their flexibility, ease of administration, high patient compliance, and fast dissolution. They are also more stable compared to oral gels making them a desirable candidate to deliver many small and large molecules locally or systemically. Mucoadhesion and mechanical properties of oral films are crucial in their performance, and therefore ways to measure these properties are also similarly important. Since they are relatively new to the pharmaceutical market, there are currently no FDA-recommended or USP standard methods available to characterize such dosage forms. This review intends to cover and discuss various methods cited in the literature to measure and evaluate mucoadhesive and mechanical properties of oral films.