Solid Dosage Forms (Tablets) Flashcards
(29 cards)
Why is powder flowability important in tablets?
Ensures consistent ingredient blending, aka uniformly dosed tablets.
How does particle size affect powder flow?
Larger particles have better flowability than smaller particles
Why do smaller particle sizes have poorer flowability?
Increased surface area in smaller particles increases interparticle forces making them stick together.
How does Particle size distribution affect flowability?
Uniform sized particles flow better than widely distributed sizes
Why do uniformly sized particles flow better?
Particles don’t pack tightly together (small fill the gaps between big particles), decreasing friction and cohesion
How does particle shape affect flowability?
Spherical particles have less friction, so have better flowability.
How does density and porosity affect flowability?
Particles with high density and low porosity tend to have better flowability.
How does moisture of powder affect flowability?
Higher moisture causes cohesion and therefore poorer flowability.
What is the maximum moisture rate for powders?
0.5-1%
What are the two methods of tablet production?
Direct compression and Compression with Granulation (wet or dry)
What is wet granulation?
Adding water or binder to the process to improve flowability
When would a manufacturer use wet granulation?
If powder has poor compressibility or the ingredients mix poorly
What are some common manufacturing problems for tablets? (7)
Capping and laminating/splitting, sticking, chipping, cracking, binding and mottling.
What are the six quality control tests?
Uniformity of mass, uniformity of content, disintegration test, dilution test, resistance to crushing, friability test
How is mass uniformity measured?
20 random tablets are individually weighed and used to determine average weight
What are the conditions to pass the mass uniformity test?
- no more than 2 individual masses should deviate from the average mass by more than the percentage deviation.
- no tablet should be deviated by more than twice that percentage
How is the deviation calculated
[(average weight - weight of tablet) / average weight ] x 100
How is uniformity of content measured?
10 random tablets are measured for content
What are the conditions to pass uniformity of content test?
If each individual unit is between 85% - 115% of the average content.
What is the disintegration test?
6 random tablets placed in individual tubes and dunked 28-32 times in water bath (37 degrees celsius)
How can you pass a disintegration test?
All six tablets must disintegrate within specified time
What is the dissolution test?
That that measures the appropriate release of active substances.
What are the 4 types of apparatus used for dissolution test?
Basket, Paddle, Reciprocating cylinder, flow through cell
What are the conditions to pass the test?
At least 75% of the active substances is released within 45 mins
