بررسی کاربرد ماتریکسها به منظور فرمولاسیون قرصهای روتارد کاربامازپین

Abstract

historiccally ,the oral administration has been the most utilized route for both conventional and novel drug delivery systems. there are many obvius reasons for this , not the list of which are acceptance by the pationt and ease of administration. in this study the preparation and invitro characterization of extendedrelease tablets of carbamazepine were carid out. this study also examined the effects of various parameters including type of polymer, drug:polymer ratio, drug particale size, compression pressure, type of diluent and different surfactants on the release of carbamazepine from HPMC K4M matrices. the results showed that an increase in HPMC K4M, carbopol 934P NaCMC and eudragit RS content resulted in a decrease in the percent of drug relesed. in other words the major factor controlling the relese of drug frpm matrices is the drugpolymer ratio. addition of lactose into the matrices increased the release rate of carbamazepine. release rate of carbamazepine from HPMC K4M matrices prepared by the wet granulation was faster than that of matrices prepared by direct compression. the compression pressure had no effect on the release rate of carbamazepine, but altered the kinetic of release. decreasing in the particle size of the drug resulted in an increase in the release rate of carbamazepine and reduction of the diffusional exponent. the effect of partial replacement of HPMC K4M whit lactose or dicalcium phosphate werw also examined on the release rates. results indicated that there were no diffrence in the release rate of the drug despite the solubility diffrence of the dilluents. only in tablets contanining 50 mg HPMC K4M and 150 mg of lactose or dicalcium phosphate the diffrence in release rate were apparent. in fluence of various surfactants, sodium lauryl sulfate, cetyl pyridiniym chlorid and diffrent types of tween on the release of carbamazepine from HPMC K4M matrices were evaluated. results showed that the cocentration of surfactant whitin the matrix is an important parameter affecting release. the highest rate of release was observed with the lowest percent of surfactant and with increase in surfactant concentration, the release exponent was increased.