The aims of this research were to develop a novel bilayer hydrocolloid film based on alginate and to
investigate its potential as slow-release wound healing vehicle. The bilayer is composed of an upper layer
impregnated with model drug (ibuprofen) and a drug-free lower layer, which acted as a rate-controlling
membrane. The thickness uniformity, solvent loss, moisture vapour transmission rate (MVTR), hydration
rate, morphology, rheology, mechanical properties, in vitro drug release and in vivo wound healing profiles
were investigated. A smooth bilayer film with two homogenous distinct layers was produced. The
characterisation results showed that bilayer has superior mechanical and rheological properties than the
single layer films. The bilayers also showed low MVTR, slower hydration rate and lower drug flux in vitro
compared to single layer inferring that bilayer may be useful for treating low suppurating wounds and
suitable for slow release application on wound surfaces. The bilayers also provided a significant higher
healing rate in vivo, with well-formed epidermis with faster granulation tissue formation when compared
to the controls. In conclusions, a novel alginate-based bilayer hydrocolloid film was developed and
results suggested that they can be exploited as slow-release wound dressings.
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