Effect of structural viscosity on medicinal product release from hydrogel forms containing poliacrylic acid
Michał K. Kołodziejczyk, Justyna Kołodziejska, Marian M. Zgoda
Zakład Technologii Postaci Leku, Katedra Farmacji Stosowanej Uniwersytetu Medycznego w Łodzi
Objective of the study. Viscosity parameters of marketed hydrogel products with anti-inflammatory action were studied. The objective of the study was to determine the correlation between formulation-dependent rheological parameters of the study hydrogels and the pharmaceutical availability of ketoprofen.
Material and methods. The material for the study was ketoprofen acid-containing marketed hydrogel products developed on the basis of poliacrylic acid. The viscosity parameters of hydrogels were determined with the use of a cone and plate digital rheometer. In in vitro conditions examination of kinetics of release of the medicinal product contained in hydrogels through the standard type Viscing membrane to the recipient fluid was performed.
Results and discussion. Market hydrogels with ketoprofen, indicated for use on the skin, are non-Newton systems, rheologically unstable, having a viscosity limit. The lowest values of structural viscosity, hysteresis loop area and viscosity limit were obtained for the product with the formulation created on the basis of Carbopol 940.
Conclusions. The rheological parameters, i.e. the low value of structural viscosity with maintenance of a small hysteresis loop area, have an effect on the high pharmaceutical availability of ketoprofen from the marketed hydrogel products containing poliacrylic acid.
Key words: hydrogels, poliacrylic acid, viscosity, pharmaceutical availability, ketoprofen