Hydrotalcite composites for an effective fluoride buccal administration: a new technological approach

The aim of this work was to develop new mucoadhesive buccal patches containing an inorganic fluorinated compound, MgAl-F, intended for decay prevention. Firstly MgAl-F was synthesized and characterized, then the patches were prepared starting from a physical blend of mucoadhesive polymers (NaCMC and polycarbophil) in which MgAl-F was dispersed in different amounts in order to obtain the films. The prepared mucoadhesive patches were characterized in terms of swelling capacity, mucoadhesion force and time, surface morphology and in vitro release studies. Moreover, the organoleptic properties and acceptability have been evaluated by in vivo application. The performed studies demonstrated that the proposed formulations are practical, manageable, flexible and adaptable to the biological substrate showing, at the same time, good organoleptic properties. Moreover, the presence of the MgAl-F is able to decrease the strong adhesion of the employed polymers, reducing pain and irritations resulting in a high patient acceptability. Data obtained from release studies revealed that the application of small patch portions is enough able to release, for a prolonged time, an amount of fluoride ions able to reach the efficacious dose. These observations suggest the applicability of such formulations for buccal administration of different active ingredients.