Development of Novel Drug Delivery System Using Calcium Silicate

The process of dissolution plays a vital role in liberation of a drug from its dosage form and making it bioavailable for subsequent gastrointestinal absorption. This piece of work was initiated to characterize microparticles obtained by adsorption of poorly water-soluble drug, metronidazole, on a porous calcium silicate (Florite) to improve the dissolution properties of metronidazole. Metronidazole was adsorbed on the Florite in 3 proportions (1:0.5,1:1,1:3), by fast evaporation of solvent from drug solution containing dispersed Florite. Metronidazole tablets were prepared by direct compression and compared with Florite adsorbed tablets. The tablets were evaluated for mechanical and release properties of friability, hardness; disintegration test and dissolution test as evaluation parameters respectively. The prepared tablets were compared with Flagyl as standard drug. All the prepared tablets showed acceptable mechanical properties of hardness values ranging from 2.25 -2.45 kg/cm2 which implies that the tablets are less hard than Flagyl tablets having hardness of 2.75kg/cm2. The friability test results were less than 1% with values ranging from 0.21- 0.23 % for compressed tablets. For the release properties, disintegration times of the prepared tablets were 50 secs for B1 tablets, 61 secs for B2 tablets, 63.82 secs for B3 tablets and 62 secs for metronidazole tablets compressed without calcium silicate (B4). The results suggest FLR provides a large surface area of drug adsorption in a smaller ratio resulting in improved drug dissolution. Keywords— Calcium