physical mixtures of benfotiamin at three different mass ratios ( 1:1 , 1:2 , 1:3 and 1:4 ) were prepared .
the prepared mixtures were then filled in glass bottles , sealed and stored in a dessicator until further use .
a mixture of drug and polymers in three different mass ratios were wetted with water and kneaded thoroughly for 30 minutes in a glass mortar .
the dissolution study of pure drug , physical mixture and solid dispersion was carried out by using usp dissolution apparatus ( type 2 ) at 100 rpm at temperature of 37  0.5c using 900 ml volume of ml p. 1.2 and p. 7.4
the volume withdrawn was replaced by fresh volume of dissolution medium to maintain constant volume of medium .
the filtered samples were analyzed spectrophotometrically at 226 nm and the drug release was determined .
the phase solubility studies were performed to determine stoichimetric proportions of benfotiamin and carriers- pvp k-30 and hpmc .
the effects of polymers concentration at room temperature on solubility are shown in figure 1 .
results of concentration of carriers on solubility of benfotiamin the plot of drug solubility against polymer concentrations at room temperature indicated a linear relationship between drug and polymer solution .
both the type shows al type of plot i.e. the solubility of benfotiamine increased with increasing carrier concentration .
dissolution of the pure drug , physical mixtures as well as solid dispersions of benfotiamin with pvp k-30 ( equivalent to 40 mg ) was tested in acidic buffer ( ph 1.2 ) and phosphate buffer ( ph 7.4 ) for a period of 60 minutes .
dissolution of the pure drug , physical mixture and solid dispersion prepared by kneading method in ratio of 1:4 was found to be 36.63% , 41.63 and 99.72% in 50 minutes in acid buffer medium .
pure drug and physical mixtures shows almost same release , whereas the solid dispersion ( 1:4 ) shows 00% drug releases in one hour . the solid dispersion prepared using ratio 1:1 , 1:2 and 1:3 showing corresponding drug releases that is 79.29% , 83.30% and 95.12% in 60 minutes as shown in figure 2 . 
 in - vitrodissolution profile of benfotiamin with pvp k-30 in ph .
increasing the drug carrier ratio from 1:1 to 1:4 improved drug release profiles observed in for all formulations in case of kneading method with pvp k-30 and hpmc but the drug release rate was higher in 1:4 ratio for both the polymers .
the drug release was found to be better in solid dispersions prepared with pvp k-30 as compared to those prepared with hpmc .
 the present study was aimed to increase the solubility of the poorly water soluble drug benfotiamine using hydrophilic polymers ( pvp k-30 and hpmc e4 ) . 
 solid dispersions were prepared by kneading method . 
 phase solubility study , in - vitro dissolution of pure drug , physical mixtures and solid dispersions were carried out . 
 pvp and hpmc were found to be effective in increasing the dissolution of benfotiamine in solid dispersions when compared to pure drug . 
 ft - ir , differential scanning calorimetry and x - ray diffractometry studies were carried out in order to characterize the drug and solid dispersion . to conclude that 
 , the prepared solid dispersion of pvp-30 may to effectively used for the enhancement of solubility of poorly water soluble drugs such as benfotiamine . 