Friability of tablets

 

Friability of tablets

Friability

¨  Friability is a physical testing procedure of compressed and uncoated tablets to determine its strength upon exposure to mechanical shock and abrasion.

¨  This test is performed in order to find ou the durability of tablets during packing process and transportation.

¨  The apparatus used for friability test is termed as friabilator.

Friabilator

¨  Friabilator consist of a drum that is attached to a horizontal axis of a rotating device.

¨  The drum used is made up of a transparent synthetic polymer having polished internal surface and having one detachable side.

¨  It has an internal diameter of 287±4 mm.

¨  Depth of the drum varies in between 36 to 40mm.

¨  A curved projection having inside radius of 80.5mm ± 5 ranges from the middle to the outer wall of the drum.

¨  The drum rotates at a speed of 25 ± 1 revolution per minute with the help of horizontal axis of the rotating device.

¨  Tablets roll down or slide upon the curved projection and falls on the drum wall or onto each other when the drum is rotating.

Procedure

¨  Tablets having compressed weight of equal to or less than 650mg the sample weight taken for the test would be 6.5 gram.

¨  Tablets having compressed weight of more than 650mg sample of random 10 tablets would be taken.

¨  First of all the tablets should be properly dedusted.

¨  After dedusting weight accurately the tablets sample and note the weight as W1.

¨  Now placed the sample in the drum.

¨  Run the friabilator at a speed of 25 ± 1 rpm for 4 minutes i.e 100 revolution.

¨  Remove the tablets from the drum and clean from any loose dust as previously performed and weight it again.

¨  This weight would be designated as W2.

¨  Calculate the weight loss by the following formula.

¨  Weight loss=    W1- W2    × 100

                                             W1

¨  If the weight loss is more than 1% or any of the tablets show a breakage, crack or capping the test sample is considered to be failed.

¨  The test is generally performed single time.

¨  However in case of any crack, breakage, capping or weight loss of more than prescribe range the test should be repeated twice.

¨  An average of the three samples weight loss not exceeding 1.0% is considered acceptable.

Note

¨  Effervescent, chewable and hygroscopic tablets may have different specifications regarding friability testing.

 Presented by

Muhammad Atif

PhD Scholar Pharmaceutical Sciences 

Abdul Wali Khan University Mardan, Pakistan