Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
18 Cards in this Set
- Front
- Back
|
Define: compression |
Reducing volume of powder by application of force, pushing gas out.
Happens in a die between two punches. |
|
|
Define: consolidation |
Increase in mechanical strength of the material resulting from compression. |
|
|
What are the three stages of tablet formation? |
1. Die filling (powder flows into die) 2. Tablet formation (compression and consolidation by upper punch) 3. Tablet ejection |
|
|
Define: tablet lamination |
During tablet decompression, the tablet will expand axially. If the bonds between the particles are not tight enough, the layers will fall apart. |
|
|
Define: tablet capping |
When tablet is ejected, it undergoes radial expansion. If lamination occurs, it happens on the upper edge. |
|
|
How can tablet capping and lamination be prevented? (3) |
1. Add more binder 2. Add lubricant to prevent tablet from sticking to upper punch 3. Apply force for a longer period of time. |
|
|
What is the average output for single punch presses? |
200 tablets per minute - primarily used for making small batches of tablets for research. |
|
|
What is the average output for rotary presses? |
Multistation press, so output is over 10,000 tablets per minute. - large scale production |
|
|
What are common problems in tablet formation? |
1. Weight and dose variation 2. Low mechanical strength 3. Lamination and capping 4. Material stuck to the punches 5. High friction during tablet ejection |
|
|
How can you test the uniformity of tablet ingredients? |
Conduct an assay for the active ingredient on 10 tablets. Should be +/- 15% of the active ingredient. |
|
|
How can you test the uniformity of tablet weight? |
Weight 20 tablets.
Less than 80 mg: +/-10% 80 to 250mg: +/-7.5% Greater than 250mg: +/-5% |
|
|
When is testing the uniformity of tablet weight not appropriate? |
When testing drugs that are very potent with a high therapeutic index.
Example: digoxin is very potent, so most of the drug is not the API. Slight differences in tablet weight could mean a huge difference therapeutically. |
|
|
Define: disintegrating testing |
A test is carried out by agitating a given number of tablets in an aqueous medium at a defined temperature, and the time to reach the end point of the test is recorded.
Tablets are placed in a basket and lowered into a tube with aqueous ingredient continuously. |
|
|
Define: dissolution testing |
A method of studying, in vitro, the release of a drug from a solid dosage form. The amount of drug that passes into solution is measured over time. A tablet is placed into a chamber containing a flowing dissolution medium. |
|
|
Define: sink conditions |
A sink is the material of interest disappearing/ flowing out of the system. |
|
|
How does mechanical strength affect the tablet? |
1. Disintegration and dissolution rate 2. Physical stability - chipping upon shipping 3. Ability to split tablet (some may be too crumbly) |
|
|
What are attrition resistance/ friability tests? |
This tests mimics the forces a tablet is subjected to between production and administration. Weight loss of less than 1% is required.
Common tests: 1. Rotate tablets in a cylinder, then determine weight lost 2. Shake tablets intensively in a jar |
|
|
What are fraction resistance tests? |
Requires the application of a load on a tablet and determining the force needed to fracture the tablet. This is especially important for medication in blisters. |
