This document evaluates various properties of tablets including size, shape, thickness, friability, weight variation, disintegration, and dissolution. It describes common tests used to analyze these properties, including friability testing to measure how easily tablets crumble, weight variation testing to check consistency of tablet weights, disintegration testing using glass tubes in fluid, and dissolution testing using apparatus 1 (basket type) or apparatus 2 (paddle type) to measure how quickly drugs dissolve. The document provides details on procedures, equipment, and standards used for these pharmaceutical quality control tests.

1. Evaluation of Tablet
Md. Shohag Hossain (131-29-473),
Nasir Uddin (131-29-474),
Md. Salman (131-29-476).

3. Size & Shape
• It can be dimensionally described &
controlled.
• The thickness of a tablet is only variables.
• Tablet thickness can be measured by
micrometer or by other device.
• Tablet thickness should be controlled within a
± 5% variation of standard value

6. % friability = (W0 – Wf / W0) x 100.
W0 = initial weight, Wf = final weight.
Why measure friability?
Tablets that tend to powder& fragment when handled:
1.lack elegance & consumer acceptance.
2.Create excessively dirty processes in areas of manufacturing as
coating & packaging.
3.Can also add to a tablet's weight variation or content uniformity

7. Weight Variation test (U.S.P.)
• Take 20 tablet and weighed individually.
• Calculate average weight.
• % Wt. Variation =(Individual wt/Average wt)x100
• The tablet pass the U.S.P. test if no more that 2 tablets are out of
% limit and if no tablet differs by more than 2 times of % limit.
Average weight Percent difference
130mg or less 10
More than 130mg
through 324mg
7.5
More than 324mg 5

8. Disintegration Test (U.S.P.):
• The U.S.P. device to test disintegration uses 6 glass
tubes that are 3inch long; open at the top and 10
mesh screen at the bottom end.
• To test for disintegration time, one tablet is placed
in each tube and the basket rack is positioned in a 1-
L beaker of water, simulated gastric fluid or
simulated intestinal fluid at 37 ± 2 C.
• Move the basket containing the tablets up and down
through a distance of 5-6 cm at a frequency of 28 to
32 cycles per minute.

9.  Floating of the tablets can be prevented by placing perforated plastic
discs on each tablet.
 According to the test the tablet must disintegrate and all particles
must pass through the 10 mesh screen in the time specified.
 If any residue remains, it must have a soft mass.
Disintegration time:
 Uncoated tablet: 5-30 minutes
Coated tablet: 1-2 hours

10. Dissolution test
• Dissolution is the process by which a solid solute enters a solution.
• In the pharmaceutical industry, it may be defined as the amount of
drug substance that goes into solution per unit time under
standardized conditions of liquid/solid interface, temperature and
solvent composition.
• Dissolution is considered one of the most important quality control
tests performed on pharmaceutical dosage forms.
• Now it developing into a tool for predicting bioavailability, and in
some cases, replacing clinical studies to determine bioequivalence.
• Dissolution behavior of drugs has a significant effect on their
pharmacological activity.
• In fact, a direct relationship between in vitro dissolution rate of
many drugs and their bioavailability has been demonstrated.
• It is generally referred to as in vitro-in vivo correlation(IVIVC)

12. Apparatus-1 (Basket Type)
• A single tablet is placed in a small wire mesh basket attached to
the bottom of the shaft connected to a variable speed motor.
• The basket is immersed in a dissolution medium contained in a
1000 ml flask. The flask is cylindrical with a hemispherical bottom.
• The flask is maintained at 37±0.5˚ C by a constant temperature
bath.
• The motor is adjusted to turn at the specified speed and sample
of the fluid are withdrawn at intervals to determine the amount
of drug in solutions.

13. Apparatus-2 (Paddle Type )
• It is same as apparatus-1, except the basket is replaced by a paddle.
• The dosage form is allowed to sink to the bottom of the flask before
stirring.
• For dissolution test U.S.P. specifies the dissolution test medium and
volume, type of apparatus to be used, rpm of the shaft, time limit of
the test and assay procedure for the API.
• The test tolerance is expressed as a % of the labeled amount of drug
dissolved in the time limit