In-vitro and in-vivo availability of certain antidiabetic polymer systems from oral dosage form

Recently much attention has been focused on problems of bioavailability of poorly settable drugs . When an insoluble drug was administered orally , the rate of absorption and or the extent of biological activity are controlled by many physical and biochemical processes viz : the diffusion of drug in system , action of enzyme , dissolution rate and protein binding .In this investigation research has been made to improve the dissolution rate of both the poorly water soluble glibeclamide and tolbutamide drugs by dispersing of the drug in an inert carrier namely : PVP , polaxamer : PEG : various polyols ; area ; cholesterol and cholesterol esters prepared either by melting ( fusion ) or solvent method.In-vitro dissolution pattern of drug from drug-carrier systems of the different prepared pharmaceutical forms was evaluated in both hydrochloric and phosphate buffer .Release rate of both glibenclamide and tolbutamide were found to agree with a first order reaction .The possibility of drug interaction that may occur between drug and each of the carrier was investigated . Also the dissolution rate studies and chromatogramic behavior of the stored drug-carrier were systems were repeated every three months for one year .