Master of Pharmacy: Pharmaceutical Technology and Drug Delivery Systems Flashcards
7 cards from real MPharm Master of Pharmacy practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Master of Pharmacy: Pharmaceutical Technology and Drug Delivery Systems flashcards as text
Which nanoparticle property is measured by the polydispersity index (PDI), and what PDI value indicates a monodisperse distribution?
Answer: Particle size distribution uniformity; PDI < 0.1
PDI measures the width of nanoparticle size distribution; a PDI less than 0.1 indicates a very narrow, monodisperse population, which is desirable for reproducible drug delivery.
In mucoadhesive drug delivery systems, which polymer property is most critical for achieving strong mucoadhesion?
Answer: Presence of hydrogen-bonding functional groups (e.g., hydroxyl, carboxyl)
Mucoadhesive polymers adhere to mucus via hydrogen bonds, electrostatic interactions, and chain interpenetration; functional groups like –OH and –COOH are essential for these interactions.
Which in vitro dissolution test apparatus is most appropriate for evaluating drug release from transdermal patches?
Answer: USP Apparatus 5 (paddle over disk)
USP Apparatus 5 (paddle over disk) is specifically designed for transdermal drug delivery systems, where the patch is placed on a disk at the bottom of the vessel beneath the paddle.
What is 'hot-melt extrusion' primarily used for in pharmaceutical manufacturing?
Answer: Creating amorphous solid dispersions to enhance solubility of poorly soluble drugs
Hot-melt extrusion converts crystalline poorly-soluble drugs into amorphous solid dispersions in a polymer matrix, significantly enhancing dissolution rate and oral bioavailability.
In self-emulsifying drug delivery systems (SEDDS), what happens upon dilution with GI fluids after oral administration?
Answer: The lipid-surfactant mixture spontaneously forms an oil-in-water emulsion or microemulsion
SEDDS contain oil, surfactant, and cosurfactant in ratios that allow spontaneous emulsification under gentle agitation of GI motility, presenting hydrophobic drugs in a finely dispersed, readily absorbable form.
Which rheological property of a gel formulation is described by the term 'thixotropy'?
Answer: Time-dependent reversible decrease in viscosity upon shearing, recovering at rest
Thixotropic gels show a time-dependent decrease in viscosity when subjected to shear (facilitating spreading/injection) and rebuild their structure when shear is removed, which is desirable for topical and injectable gels.
What is the role of cryoprotectants (e.g., trehalose, mannitol) in lyophilized biological drug products?
Answer: They prevent ice crystal formation from damaging protein structure during freezing
Cryoprotectants form a glassy amorphous matrix around protein molecules during freezing, replacing water hydrogen bonds and preventing ice crystal-induced conformational denaturation.