MPharm Master of Pharmacy Master of Pharmacy: Pharmaceutical Technology and Drug Delivery Systems 1

Question 1

Which parameter in the Noyes-Whitney equation directly describes the rate of drug dissolution?

Accepted Answer

Surface area of the dissolving solid

Answer

The Noyes-Whitney equation states that dissolution rate is directly proportional to the surface area of the solid, so smaller particle size (larger surface area) increases dissolution.

Question 2

In liposomal drug delivery, what is the term for liposomes engineered to avoid rapid clearance by the mononuclear phagocyte system?

Accepted Answer

Stealth liposomes

Answer

Stealth liposomes are coated with polyethylene glycol (PEG), which creates a hydrophilic shield that prevents opsonization and prolongs circulation time.

Question 3

Which type of controlled-release mechanism relies on osmotic pressure to drive drug release at a constant rate?

Accepted Answer

Elementary osmotic pump (OROS)

Answer

The elementary osmotic pump uses a semipermeable membrane and an orifice; water enters by osmosis, creating pressure that pushes drug solution out at a controlled zero-order rate.

Question 4

What is the primary purpose of using a plasticizer in film-coating of tablets?

Accepted Answer

To improve flexibility and reduce brittleness of the coating film

Answer

Plasticizers like polyethylene glycol or triethyl citrate are incorporated into polymer coatings to reduce glass transition temperature, making the film more flexible and preventing cracking.

Question 5

Which emulsification theory explains stabilization of emulsions by the formation of a monomolecular film at the oil-water interface?

Accepted Answer

Interfacial film theory

Answer

The interfacial film theory states that emulsifying agents form a condensed, coherent monomolecular film at the interface that mechanically prevents coalescence of droplets.

MPharm Master of Pharmacy Practice Test

MPharm Master of Pharmacy Practice Test

MPharm Master of Pharmacy Master of Pharmacy: Pharmaceutical Technology and Drug Delivery Systems 1