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Development of hot-melt extrusion as a novel technique for the ...

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in <strong>the</strong> range <strong>of</strong> 10-12 kP. However, in our c<strong>as</strong>e we observed slightly lower hardness valuethan expected but <strong>the</strong> all tablets still seemed to be very robust <strong>as</strong> <strong>the</strong> weight loss percentageafter 10 min in friability test w<strong>as</strong> only 0.01. This could be due to <strong>the</strong> presence <strong>of</strong> el<strong>as</strong>ticpolymers (Eudragit ESPO) in <strong>the</strong> final tablet composission. The el<strong>as</strong>ticity present in <strong>the</strong>tablets h<strong>as</strong> finally managed to attribute this lower hardness value with less friability and thushigher robustness.Table 8.2: Drug/polymer‘s description; tablet characterization.FormWeight(mg)Thickness(mm)Average(mm)/SDHardness(kP)Average(mm)/SDFriability(%)HCS /250.0 3.456.2EC N10250.0 3.43 3.44/±0.012 6.0250.0 3.45 5.96.0/±0.15 0.01HCS /250.0 3.506.1EC P7250.0 3.49 3.50/±0.010 6.2250.0 3.51 6.06.1/± 0.10 0.013.6 In vitro dissolution studiesPolymeric coating <strong>of</strong> <strong>the</strong> compressed tablets with 15% pH dependent polymer provedsufficient to provide 2 hrs lag time in an acidic medium (Fig. 8.4). The composition <strong>of</strong> <strong>the</strong>matrix core <strong>of</strong> <strong>the</strong> final tablet <strong>for</strong>mulation included a combination <strong>of</strong> hydrophilic (HPMC)and lactose along with extruded ethylcellulose to control HCS rele<strong>as</strong>e patterns. Thecombination <strong>of</strong> all three ingredients provided retarded rele<strong>as</strong>e pr<strong>of</strong>iles <strong>of</strong> HCS at higher pHvalues when <strong>the</strong> dissolution <strong>of</strong> <strong>the</strong> coating layer occurred [25] . The rele<strong>as</strong>e pr<strong>of</strong>ile w<strong>as</strong> alsocontrolled from <strong>the</strong> polymer amount coated on <strong>the</strong> surface <strong>of</strong> <strong>the</strong> matrix tablet.161 | P a g e

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