Chrominfo: Calibration of friability test apparatus as per USP

Learn the calibration process of the friability test apparatus, which is used to determine how much mechanical stress a tablet can tolerate throughout manufacturing, client handling, and delivery.

Quantitative evaluations and assessments of the chemical, physical, and bioavailability properties of tablets are required for tablet design and post-formulation quality monitoring. The tablet is subjected to various quality control and post-production tests such as hardness, friability and disintegration, and dissolution rate of the standard pharmacopeia such as USP, BP, and IP procedures.

Friability testing is a quality control test for tablet dosage forms that follow official standards outlined in pharmacopeias (USP), which also includes standard ranges. When compressed or uncoated tablets are subjected to mechanical shock and attrition, friability tests are used to determine their physical strength. The equipment used to carry out this method is called a friability tester or friabilator. Friability testing has become a well-recognized practice in the pharmaceutical industries and research.

It consists the repeatedly dropping a sample of the tablet over a set amount of time, using a drum that rotates with a spin. 10 whole tablets are weighed, (If the weight of one tablet is 650 mg or less then approximately 6.5 g of total weight should be taken and 10 tablets should be taken for those weighing more than 650 mg/tablet) then inserted into the fabricator’s drum, where it is rotated. Broken tablets are evaluated and the percentage of tablet mass lost due to chipping is calculated. As per USP, IP and BP, the friability should not exceed 1.0%.

Procedure for calibrating a friability tester:

The calibration of the friability test apparatus consists of rpm calibration, timer calibration, and the number of counts calibration.
Make sure the appliance is clean and properly connected to the power supply.
Switch on the instrument.
When the power is on, the drum will automatically adjust to the loading position.

RPM calibration:

Set the RPM value to 25.
Run the machine for 4 minutes and count the rotations.
Manually count the number of counts and record it.
RPM is calculated using the formula RPM=Total rotations/4.
Repeat the same process for 50 and 100 RPM.

Timer calibration:

Set a timer for 4 minutes and operate the instrument.
Observe the time shown by the machine and the stopwatch and record it in the calibration format.
Repeat the same process 8 to 12 times.