Tablet Friability

 Title

Tablet Friability

Aim

To determine the physical strength of compressed tablets upon exposure to mechanical shock.

Introduction

Friability is a measure of the resistance of the tablets to shipping and abrasion. The purpose of having friability test is to make sure that the tablets formed able to withstand mechanical stresses during their manufacturing, distribution and handling by the end-user.

The friability test is done by tumbling the tablets in a rotating drum. In this experiment, a roche friabilator is used. Roche friabalitor consist of a drum of transparent synthetic polymer with polished internal surfaces, and subject to minimum static build-up. One side of the drum is removable. The tablets are tumbled at each turn of the drum by a curved projection that extends from the middle of the drum to the outer wall. The drum is attached to the horizontal axis of a device that rotates at 25rpm. Thus, at each turn the tablets roll or slide and fall onto the drum wall or onto each other. After tumbling, the integrity of the tablets and the weight loss are evaluated. The compressed tablets shall not lose more than 1% of weight after the test.

Material

10 tablets of Ettrocin

Apparatus

Roche friabilator, electronic balance, spatula and weighing boat

Procedure

1.      10 tablets are selected and weighed.

2.      All tablets are put into the drum of the tablet abrasion and friability tester. The rate of rotation is set to 25rpm, the time to 10 minutes and the operation is started.

3.      At the end of the operation, all the tablets are removed and freedom from dust or powder is ensured using the brush. The tablets are reweighed. The percentage loss of weight is determined.

4.      Compressed tablet should nor loss more than 1% of its weight.

Results and calculation

The total weight of 10 Ettrocin tablets BEFORE undergoing friability test: 6.6348 g

The total weight of 10 Ettrocin tablets AFTER undergoing friability test: 6.6134 g

Loss of weight = 6.6348 – 6.6134= 0.0214g

The percentage loss of weight = [(0.0214) / (6.6348)] x 100% = 0.3225%

Discussion

After the friability test, the percentage of loss of weight of 10 Ettrocin tablets is 0.3225% which is lower than 1%. Hence, we can say that the tablets comply with the non-pharmacopoeial standards for compressed tablet. Once the percentage of weight loss of the tablets exceeds 1%, the tablets are considered fail the friability test and thus show that the tablets are not in good quality. It can be caused by a number of factors including poor tablet design (too sharp edges), low moisture content, insufficient binder and others.

In the friability test, tablets are allowed to tumble in the rotating drums. Some fragment of the tablets may be broken due to the impaction and abrasion. Hence, after the friability test, it is important to ensure that the tablets are free form dust and any broken fragment before evaluating the loss of weight in order to get an accurate result. However, some error might still occurred in the experiment as the dust or powder which stick on the surface of tablets cannot be cleaned thoroughly as they are too small and cannot be seen with naked eyes.

Conclusion

The 10 Ettrocin tablets have a percentage loss of weight of 0.3225% which is less than 1%. So, we can conclude that the tablets comply with the friability test.

Reference

1.  http://www.anabiotec.com/testing/detail/hardness-friability-disintegration 
2. http://www.copleyscientific.com/home/pharmaceutical-testing/friability-testing/introduction-to-friability-testing 
3. http://www.who.int/medicines/publications/pharmacopoeia/TabletFriability_QAS11-414_FINAL_MODIFIED_March2012.pdf