PHRM 4200- Dissolution Exam
Study Guide
What is dissolution? - Answer the process of dissolving drug from a solid state into
solution
When is dissolution in equilibrium? - Answer the solid drug and the drug in solution are
at equilibrium when the solution is saturated (at a given temp, pH, pressure)
interfacial reaction - Answer where the bulk solid drug meets the solvent; the solvent
attacks the solute particles to release them from the bulk drug (adhesion)
Where in the dissolution diagram are there cohesive forces? - Answer in the bulk drug
and in the bulk solution
Where in the dissolution diagram are there adhesive forces? - Answer where the drug
and solvent particles meet
What process is the opposite of dissolution? - Answer precipitation
What are the 4 steps of how a solid drug gets to systemic circulation? - Answer -
disintegration (to granules)
- deaggregation (to powder)
- dissolution (to solution)
- absorption
What happens in the process of disintegration? - Answer the tablet is disintegrated into
granules
What happens in the process of deaggregation? - Answer granules of drug are
deaggregated into powder
What is the difference between tablets and capsules in terms of the process to systemic
circulation? - Answer tablets go through all 4 steps, capsules are already in powder
form so only dissolution and absorption
the rate of dissolution is a function of ___ - Answer diffusion (determined by the
movement of dissolved drug from the solid surface into the bulk solvent)
What is the diffusional region? - Answer the area where bulk drug is moved away
towards bulk solution
What is the stagnant diffusion layer? - Answer the area where bulk drug and bulk solvent
meet and interact for the first time
Study Guide
What is dissolution? - Answer the process of dissolving drug from a solid state into
solution
When is dissolution in equilibrium? - Answer the solid drug and the drug in solution are
at equilibrium when the solution is saturated (at a given temp, pH, pressure)
interfacial reaction - Answer where the bulk solid drug meets the solvent; the solvent
attacks the solute particles to release them from the bulk drug (adhesion)
Where in the dissolution diagram are there cohesive forces? - Answer in the bulk drug
and in the bulk solution
Where in the dissolution diagram are there adhesive forces? - Answer where the drug
and solvent particles meet
What process is the opposite of dissolution? - Answer precipitation
What are the 4 steps of how a solid drug gets to systemic circulation? - Answer -
disintegration (to granules)
- deaggregation (to powder)
- dissolution (to solution)
- absorption
What happens in the process of disintegration? - Answer the tablet is disintegrated into
granules
What happens in the process of deaggregation? - Answer granules of drug are
deaggregated into powder
What is the difference between tablets and capsules in terms of the process to systemic
circulation? - Answer tablets go through all 4 steps, capsules are already in powder
form so only dissolution and absorption
the rate of dissolution is a function of ___ - Answer diffusion (determined by the
movement of dissolved drug from the solid surface into the bulk solvent)
What is the diffusional region? - Answer the area where bulk drug is moved away
towards bulk solution
What is the stagnant diffusion layer? - Answer the area where bulk drug and bulk solvent
meet and interact for the first time
