3. Enteric coated tablets If the tablet has a soluble external coating, immerse the basket in water at room temperature for 5 minutes. Suspend the assembly in the beaker containing 0.1M hydrochloric acid and operate without the discs for 120 minutes , unless otherwise stated in the individual monograph. Remove the assembly from the liquid. No tablet shows signs of cracks that would allow the escape of the contents of disintegration, apart from fragments of coating. Replace the liquid in the beaker with mixed phosphate buffer pH 6.8 , add a disc to each tube and operate the apparatus for a further 60 minutes. Remove the assembly from the liquid. The tablets pass the test if all six have disintegrated. 4. Dispersible and Soluble Tablets: Disintegrate within 3 minutes when examined by the disintegration test for tablets and capsules, using water at 24 o to 26 o , unless otherwise stated in the individual monograph. 5. Effervescent Tablets : Place one tablet in a 250-ml beaker containing water at 20 o to 30 o ; numerous gas bubbles are evolved. When the evolution of gas around the tablet or its fragments has ceased the tablet shall have disintegrated, being either dissolved or dispersed in the water so that no agglomerates of particles remain. Repeat the operation on a further 5 tablets. The tablets comply with the test if each of the 6 tablets disintegrates in the manner prescribed within 5 minutes , unless otherwise stated in the individual monograph. D. Uniformity of color and gloss on tablet surface is measured by micro reflectance photometer. E. Crown thickness is measured by micrometer or sliding caliper. F. Hardness tester: 2 kg ----------------- Soft 4kg --------------------Good 6kg---------------------Hard
Monsanto Hardness ‐Tester (Compressible spring held b/w two plungers) Strong – Cobb Hardness tester (uses Hydraulic pressure ) Pfizer – Hardness tester Erweka Hardness tester Schleuniger Hardness Tester (Most widely used )
G. Roche Friability tester: the plastic chamber revolves at 25 rpm . Normally preweighed tablet sample is placed in friabilator which is then operated for 100 revolutions . The tablets that less than 0.5-1% of their weight is generally acceptable. H. Tablet thickness should be controlled within ± 5 % variation of standard value. It is important for tablet packaging. DISINTEGRATION TEST FOR TABLETS AND CAPSULES This test determines whether tablets or capsules disintegrate within a prescribed time when placed in a liquid medium under the prescribed experimental conditions. For the purpose of this test, disintegration does not imply complete solution of the tablet or capsule or even its active constituent. Disintegration is defined as that state in which no residue of the tablet or capsule remains on the screen of the apparatus or, if a residue remains, it consists of fragments of insoluble coating of the tablets or of capsule shells or is a soft mass with no palpable core. If discs have been used with capsules, any residue remaining on the lower surfaces of the discs consists only of fragments of shells.
- Summer '16
- Physics, Surface tension, Granulations