Physical Pharmacy Advanced (512)

What are some chemical properties that affect drug deliver?

What are some physical properties that affect drug delivery?

How does the GI tract affect drug delivery?

How does the vaginal system affect drug delivery?

Define this:

The extent to whish a dosage form retains the same properties and characteristics that it possessed at the time of its manufacture

USP-NF<1191>

Name some chemical instabilities? (4)

Hydrolysis, oxidation, photodegradation, isomerization

Define this:

the duration of time during which at least 90% of the original expected to remain unchanged

Shelf-life

What is the difference between dissolution and solubility?

Dissolution → kinetic process quantified by its rate

Solubility → state of dynamic equilibrium

What process does the API liberate from the tablet?

Disintegration → disaggregation → dissolution

What formula do we use for drug dissolution?

Noyes-Whitney (Equation)

Why is particle size reduction important?

With a smaller particle size, the surface area to volume increases which means it increases the rate of dissolution

What are some ways of reducing particle size?(5)

Micronization, nanosuspension, sonocrystalization, supercritical fluid process and spray drying

What physical constraints increase dissolution rates? (3)

Increased surface area, driving forces, decreased diffusion-layer thickness

Define this:

The rate of movement per unit area

Flux

What equation relates to the diffusive flux of a solute to the concentration?

Fick’s first law

According to Fick first law, the greater the difference in concentration across the membrane,…

The greater the flux

What affects molecule diffusion?

Molecular kinetic energy (temp.), molecule size, material moving through, charge, properties of molecule