Preparation, characterization and evaluation of some metronidazole formulations as films and the study of their medicinal activities against pathogenetic microorganisms causing dermatitides

الملخص EN

-In the present study, a labor has been made to develop film type of transdermal therapeutic system comprising different concentrations of metronidazole with hydrophilic polymeric combinations using solvent casting (evaporation) technique.

The DSC analysis confirmed that ester bonds were formed between the used polymers in preparing the films.

The prepared films were considred semi-IPNs hydrogels and the mixture between the used polymers and metronidazole in preparing the films is considred physical mixing viz., chemical, physical and therapeutical properties of drug remained themselves.

Two main parts including chemical and biochemical were discussed in this study.

In the chemical part, the prepared films FR0R and FR3R were evaluated via the study of weight and thickness uniformities and swelling behaviour.

In vitro drug release and kinetics of drug release were studied for all the prepared pharmaceutical formulations in this study.

FR3R was higher average weight and thickness as compared to FR0R and in addition to their possession of the same swelling behaviour which was explained on the basis of the increase in swelling index up to period at 70 min and which was followed by the decrease in this index according to cleavage of the formed ester bonds in the crosslinked structure, erosion process with physical disintegration and mass loss.

Also, the prepared formulation FR3R followed zero order, Korsmeyer-Peppas model and Fickian (n<0.5) transport mechanism (diffusion controlled release).

In the biochemical part, the biochemical activities of all the prepared formulations (as antimicrobials) were studied (in vitro) in four types of microbes including Staphylococcus aureus (Gram-positive), Staphylococcus epidermidis (Gram-positive), Candida albicans (yeast) and Trichophyton sp.

(mold) by using agar diffusion method.

These formulations showed increasing in their biochemical activities against these isolates and these activities associated with the increase in drug concentrations which were loaded with the selected polymers in this study and in addition to their possession of highest antimicrobial and biochemical activities to inhibit the growth of these microbial isolates as compared to pure drug and commercial gel at (p<0.05).

Also, the prepared formulations including F0 and F3 were applied (in vivo) to skin of male rabbits for studying subacute toxicity test (LD50