INFLUENCE OF DILUENTS AND MANUFACTURING METHOD ON THE IN-VITRO DISSOLUTION OF CARTEOLOL HYDROCHLORIDE MATRIX TABLETS

The release behaviour of carteolol hydrochloride matrix tablets was in vestigated as a function of filler nature (Emcompress(R), mannitol, PE G 6000 and lactose), type of wetting liquid (Eudragit(R) L 12.5% and i sopropanol-acetone mixture 6:4) and mode of filler incorporation. The values of the technological parameters suggest that hardness was the m ost significantly affected by the three formulation factors considered . The strongest influence over the technological parameters was exerte d by the mode of filler incorporation. The kinetic data conformed with the Higuchi square root equation, except for the lots containing mann itol and isopropanol-acetone mixture that conformed to a first-order p lot. The lot containing Emcompress(R) and isopropanol-acetone mixture displayed acceptable linearity with both plots. Therefore, a non-linea r regression procedure and reduced time method were used to define wit h precision the kinetic model followed by this formulation. Release pa rameters such as the Higuchi rate constant, t(50) and dissolution effi ciency were calculated. Lots containing mannitol presented more rapid release rates due to the high solubility of this filler. On the other hand, the use of PEG 6000 as diluent significantly decreased drug rele ase. The influence of technological parameters on the release of these systems was also examined, an inverse relationship between hardness a nd dissolution efficiency being found.