Dissolution Flashcards
Def of dissolution:
process where solid phase goes into solution phase
Drug delivery system is based on…
diffusion and dissolution
Most capsules and tablets are ____ and ____ order
zero and first
Zero order is achieved via…
non-disintegrating dosage form
Examples of zero order delivery systems:
- topical/transdermal
- implantable
- oral controlled release
Dissolution is also known as…
drug release
- rate limiting step
Which kind of particles dissolve the fastest?
fine particles
The ____ a dissolution rate, the better
higher
Where do the majority of drugs get absorbed?
duodenum of small intestine b/c of SA
What are the sink conditions for the dissolution rate equation?
[solute] in bulk solution is < 20% of the solubility of solid
Factors that affect the dissolution rate:
- size and viscosity
- solubility of solid
- diffusion thickness
- particle size
Increase in viscosity leads to…
decrease in diffusion coefficient and diffusion rate
Increase in solubility of solid leads to…
increase in diffusion rate
- same with increase use of salt form
What happens to the rate if a drug is diluted?
decrease in rate
A decrease in particle size leads to…
increase in SA and dissolution rate
