PRACTICAL 3: ASSESSMENT OF QUALITY OF TABLETS AND CAPSULES (2)

EXPERIMENT 2: Uniformity Of Diameter, Thickness And Hardness

OBJECTIVES:

1.      To measure the uniformity of diameter and thickness of tablets

2.      To analyse the hardness of tablets

MATERIAL:

10 tablets, Tablet Testing Instrument (PHARMATEST PTB 311), ruler

PROCEDURE

1.      10 tablets are selected and carried out to test the uniformity of diameter, thickness and hardness by using the Tablet Testing Instrument (PHARMATEST PTB 311).

2.      The deviation of individual unit from the mean diameter should not exceed ±5% for tablets with diameter of less than 12.5% and ±3% for diameter 12.5mm or more.

Tablet	Diameter (DI) / mm	Thickness (TH) / mm	Hardness (H) / N
1	12.840	5.590	138.19
2	12.830	5.610	110.66
3	12.820	5.580	125.44
4	12.800	5.530	121.01
5	12.810	5.580	150.01
6	12.810	5.580	105.68
7	12.790	5.440	112.51
8	12.820	5.570	137.82
9	12.810	5.640	138.01
10	12.800	5.530	121.01

Tablet	Exact diameter (mm)	Average diameter (mm)	Difference in diameter (mm)
1	12.840	12.813	0.027
2	12.830	12.813	0.017
3	12.820	12.813	0.007
4	12.800	12.813	- 0.013
5	12.810	12.813	- 0.003
6	12.810	12.813	- 0.003
7	12.790	12.813	-0.023
8	12.820	12.813	0.007
9	12.810	12.813	- 0.003
10	12.800	12.813	- 0.013

Calculation for percentage of deviation

DISCUSSION:

From the experiment above, we found that the ten tablets tested have very high uniformity of diameter, thickness and also hardness.

            All of the ten tablets tested are having diameter more than 12.5 mm, which their diameters range from 12.79 mm to 12.84 mm. The mean diameter obtained by summation of the measured diameters divided by the total number of unit tested is 12.813 ≈ 12.81 mm.

            Taking the largest diameter measured, which in this case is 12.84mm, the deviation obtained is 0.211%. Meanwhile, the deviation obtained using the smallest diameter measured which is 12.79 mm is - 0.179%. Both the deviations are within the range of 3% deviation, showing that these ten tablets measured are having quite a high uniformity of diameter.

            Using the Tablet Testing Instrument (PHARMA TEST PTB 311), the thickness and the hardness of the tablets are also obtained. The thickness measured range from 5.53 mm t0 5.64 mm and the mean thickness obtained is 5.565 mm.

            Diameter, thickness and density are the three basic components that may influence the weight of one tablet. Density of the tablet increases when the compression force for the active ingredient and the recipient increases, causing the hardness of the tablet increases as well. If the tablet is too hard, it may not be able to disintegrate in the required period of time and take longer time to dissolute; meanwhile, if the tablet is too soft, it will be more difficult to be handled in subsequent processes such as shipping and packaging as it breaks easily. Theoretically, the diameter of the tablet and its density of the powder blend should remain unchanged. Thus, by monitoring the thickness of the tablet, some potential problems regarding to the tablet’s weight and the uniformity of the tablet content can be detected at the early stage.