Phase-solubility experiments were performed with triclosan (TCS) in different aqueous cyclodextrins (CD) solutions at acidic pH. Among all the CDs that were tested, the solubility of TCS varied greatly, where 2-hydroxypropyl-â-cyclodextrin (HPâCD) was the best solubiliser.
Five different alginate types were tested regarding the solubilising properties and as a gelling agent. Protanal 10/60 and Protanal 200 showed synergistic solubilising effect with HPâCD, while Protanal 120 had a decreasing solubilising effect with HPâCD. Due to alginate precipitation in the high performance liquid chromatography (HPLC) column it was not possible to obtain data for Keltone and Protanal Ester (PE).
Results showed that gels prepared from alginate and the cross-linking agent CaCl2, gave gels consisting of one big lump or several small beads. This was not seen with the alginate type PE which gave a gel good enough for diffusion studies.
The permeability of TCS from gel, rehydrated gel and lyophilized gel (LG) through semipermeable cellophane membrane was studied by using Franz diffusion cells. The flux was lowest from the rehydrated gel and highest from the gel. However, due to better stability of the formulation and the possibility of sustained release, LG was chosen for application to a wound dressing.
Important considerations must be accounted for when developing a wound dressing. Among these are homogeneity, sterilization methods, reproducibility, stability, absorbing capacity and adhesive properties.