refers to the depth or extent from one surface to another surface.
Tablet thickness
solid dosage forms usually obtained by single or multiple compression of powders or granules. in certain cases tablets may be obtained by molding or extrusion techniques, they are uncoated or coated
Tablet
a straight line passing from side to side through the center of the tablet
Diameter
the distance between the top and bottom or front and back surface of the tablet
Thickness
Tablet diameter should be controlled within a _____________________________
+ - 5% variation of standard value
Also known as “crushing strength”.
Tablet Hardness
refers to the resistance of the tablet to chipping, abrasion or breakage under conditions of storage, transportation, and handling before usage.
Hardness
The test is done by application of a load
to the edges of a tablet across a
diameter. The load is gradually increased
until the tablet fractures or break. The
value of the load at this point (crushing
force) gives a measure of the hardness of
the tablet. 3 samples are used and the
mean value is determined.
Hardness Test
Tablet hardness tester models:
- Monsato Tester
- Strong-Cobb Tester
- Pfizer Tester
- Erweka Tester
- Schleuniger Tester
- Pharma Test
- Microspan Contesar
Most primitive way and practical test for hardness of tablets
Rule of Thumb
Describes a tablet to be of proper hardness if it was firm enough to break with a sharp snap when it was held between the 2nd and 3rd fingers using thumb as fulcrum, yet didn’t break when it fell on the floor.
Rule of thumb
What is the Monsanto tester used for?
Measuring tablet hardness using a spring-loaded screw mechanism.
- It is a hand operated device in the form of a plated metal cylinder, about 150mm in length and 25 mm in diameter.
- Also known as the Stokes Hardness tester
Monsato Tester
What is the acceptable range of the monsato tester?
4 to 10 kg- ordinary compressed tablets
2 kg- sublingual tablets
2 kg- chewable tablets
10 kg- buccal tablets
- Like Stokes Monsato, it also measures the diametrically applied force required to break a tablet.
- measures the applied force in Kg required to break a tablet across its diameter. The force is produced by a manually or pressure operated pump.
-Air pump
Strong-Cobb Tester
Plier-style hardness tester with a spring compression system.
- Tablet is crushed in between the jaws of the device. The force is indicated on the dial indicator.
Pfizer Tester
Uses the principle of a steelyard balance to load a vertically sliding jaw by means of weighted beam.
-Suspended weight
Erweka Tester
- Also known as Heberlein Model
- Most widely used instrument for tablet hardness test
- The earliest version of this instrument had no motor drive, but were operated by means of a handwheel.
- Uses an ingenious arrangement of levers
- Platens
Schleuniger Tester
Apparatus manufacturers from West Germany
Pharma Test
- Designed with the object if providing measurement not only of tablet hardness, but also thickness and weight.
- This machine is unique that it can accept mixed batches of tablets of different shapes and sizes, automatically moving them to stations for the successive measurement of thickness, weight and hardness.
-can print out statistical analysis
Microspan Contestar
determines the percentage loss on tablet
in packaging, handling, and shipping.
Friability test
Makes use of a tumbling apparatus where tablets are exposed to rolling and repeated shocks from free fall within the apparatus.
Conditions: 100 revolutions in 4 minutes.
Roche Friabilator
How many tablets are used if the tablet weight is more than 650 mg?
10 tablets
How many tablets are used if the tablet weight is 650 mg or less?
20 tablets
