Lecture 6

Question 1

Why oral solution faster than tablet?

Answer 1

Can begin absorption straight away, tablet has to dissolve first; slower

Question 2

Solution?

Answer 2

Mixture of two or more components that form a single homogeneous (uniform distribution of the drug in solvent) phase.

Question 3

Dissolution?

Answer 3

Process by which a solid dissolves in solvent to produce a solution, multiple steps: particles composed of crystals, individual molecules break off (particle->crystal->molecule)

Question 4

Disintegration?

Answer 4

Tablets turns to granules

Question 5

De-aggregation?

Answer 5

Granules turn to particles

Question 6

Solubility?

Answer 6

Amount that goes into a solution when equilibrium is established between the solute in solution and the excess (undissolved) substance.

Question 7

Dissolution process?

Answer 7

Solid particles have diffusion layer, collect solvent molecules around surface creating shell = barrier to dissolution, drug has to escape layer to dissolve
Individual molecules reach surface of layer and are available for absorption now

Question 8

How concentration gradient between intestine and blood retained?

Answer 8

Drug is always transported away in blood (high in intestine, low in blood)

Question 9

Factors that increase dissolution rate?

Answer 9

Higher SA, faster stirring (lower h - thickness of diffuse layer), higher Cs (saturated solubility)