Final Exam: Most Missed Questions Flashcards
(17 cards)
Consider a suspension of sulfadiazine with an average diameter of 26 um. Which one of the following makes the suspension settle most quickly? Density of sulfadiazine is 1.5 g/mL.
A. Add diluted bentonite magma to form floccules.
B. Reduce sulfadiazine particle size to 2.6 um by spray drying and use water as a vehicle.
C. Add methylcellulose to increase viscosity of water to 200 cps.
D. Reduce particle size to 10 um by jet milling and increase water viscosity to 100 cps.
E. Replace water with sorbitol solution (density: 1.3 g/mL, viscosity: 110 cps)
A. Add diluted bentonite magma to form floccules.
Rationale: Floccules will settle fast (but can be resuspended easily by shaking); all other options will delay sedimentation to different extents.
Consider the figure that describes the relationship between [KH2PO4] added to the suspension vs. the sediment volume of the suspension. What describes the zone highlighted by a red box (non-caking zone) in the figure best?
A. The suspension turned into a dispersed suspension.
B. H2PO4- neutralized the surface charge of the dispersed particles.
C. The dominant inter-particle force is repulsive force.
D. The suspension does not settle.
E. The suspension forms cloudy supernatant when settled.
B. H2PO4- neutralized the surface charge of the dispersed particles.
Rationale: It is not a dispersed suspension because it is non-caking. Flocculation occurs and the surface charge is neutralized. Repulsive and attractive forces are in balance. The floccules settle to produce a sediment with high volume. Controlled flocculation produces a clear supernatant.
Which of the following is NOT relevant to the structured vehicle system? Choose all that apply.
A. Thixotropy
B. Newtonian Flow
C. Shear-Thinning
D. Plastic Flow
E. Dilatant Flow
B. Newtonian Flow
E. Dilatant Flow
Rationale: Structured vehicle systems are thixotropic, which includes plastic and pseudoplastic (shear thinning). Plastic and pseudoplastic represent non-Newtonian flow, and dilatant flow represents shear-thickening.
USP 797 (Pharmaceutical Compounding- Sterile Preparations) describes the standards to be followed to minimize harm, including death, to human and animal patients that could result from the following. What are the risks unique to parenteral preparations? Choose two.
A. Microbial contamination
B. Excessive bacterial endotoxins
C. Variability from the intended strength of correct ingredients
D. Physical and chemical incompatibilities
E. Chemical and physical contaminants
F. Use of ingredients of inappropriate quality
A. Microbial contamination
B. Excessive bacterial endotoxins
Rationale: The other options are also concerns for non-sterile compounds. Sterile compounds must be free of microbial organisms (sterile). Endotoxins are pathogenic contaminants that produce fever and septic shock and are remnants of microorganisms.
Consider the degradation rate constant profile of vincristine in the figure. To design a buffer for storage of aspirin, which pair of acid and salt is the most appropriate?
A. Acetic acid and sodium acetate
B. Citric acid and monosodium citrate
C. Phosphoric acid and monosodium phosphate
D. Disodium citrate and trisodium citrate
E. Disodium phosphate and trisodium phosphate
A. Acetic acid and sodium acetate
Rationale: The k (rate constant for degradation) is the lowest at pH ~5. (i.e., the drug degrades slowest at this pH). Therefore, you want to store the drug at a pH of 5. A pair with a pKa value closest to the desired pH will have the best buffering capacity (i.e., can maintain the pH of the solution well with a minimal concentration). Of the choices, acetic acid and sodium acetate pair has a pKa value of 4.76, which is closest to a pH of 5.
Which of the following will produce a buffer solution of pH 7.4 with a buffering capacity of 0.1?
A. Acetic acid 0.00042 mol and sodium acetate 0.18 mol in 1 L of water
B. Citric acid 0.00042 mol and monosodium citrate 0.18 mol in 1 L of water
C. Phosphoric acid 0.072 mol and monosodium phosphate 0.11 mol in 1 L of water
D. Monosodium phosphate 0.072 mol and dipotassium phosphate 0.11 mol in 1 L of water
E. Dipotassium phosphate 0.11 mol and trisodium phosphate 0.072 mol in 1 L of water
D. Monosodium phosphate 0.072 mol and dipotassium phosphate 0.11 mol in 1 L of water
Rationale: Choose acid/salt pair with pKa value closest to 7.4. Confirm the concentrations of acid and salt, pKa, and given beta value of 0.1 using the Van Skyle equation.
The following ingredients stabilize an emulsion product by reducing interfacial tension or forming a steric barrier around dispersed droplets. Which of the following stabilizes the emulsion by a different mechanism than the others?
A. Bentonite
B. Sodium lauryl sulfate
C. Magnesium aluminum silicate
D. Aluminum hydroxide
E. Charcoal
B. Sodium lauryl sulfate
Rationale: Sodim lauryl sulfate is a surfactant (lowering surface tension); all others are fine particles that adsorb at the interface and serve as a steric barrier to coalescence of emulsified droplets.
Compounded sterile preparations (CSPs) can be prepared in local pharmacies producing traditional compounds as long as the facilities follow section 503A of the Federal Food, Drug, and Cosmetic Act.
A. True
B. False
B. False
Rationale: Must follow section 503B, the Drug Quality and Security Act. A new category of compounders, called an “outsourcing facility,” held to higher production standards than other facilities producing traditional compounds. They must also follow USP 797.
LVPs are:
A. Single dose injections packaged in a container containing more than 50 mL
B. Single dose injections packaged in a container containing less than 50 mL
C. Single dose injections packaged in a container containing more than 100 mL
D. Multiple dose injections packaged in a container containing less than 100 mL
E. Single or multiple dose injections packaged in a container containing more than 100 mL
C. Single dose injections packaged in a container containing more than 100 mL
Rationale: SVPs are single dose injections containing 100 mL or less.
You have a solution of Ceftriaxone Sodium dissolved in SWFI, containing the equivalent to 1 g of Ceftriaxone in a total volume of 20 mL. What amount of glycerol do you need to add to the solution in order to obtain an osmolarity value of 280 mOsmol/L? (Ignore volume increase due to glycerol. Round up to the nearest whole number.)
Ceftriaxone MW = 554.48
Glycerol MW = 92.09
Sodium atomic weight = 22.98
A. 9 mg
B. 18 mg
C. 92 mg
D. 184 mg
E. 350 mg
D. 184 mg
Rationale: Osmolarity of Ceftriaxone 1g/20mL= (1 g / 20 mL)(1000 mL / 1 L)(1 mol / 554.98 g)(1 Osmol / 1 mol)(1000 mOsmol / 1 Osmol) = 90.17 mOsmol/L
As Ceftriaxone sodium (ionizes into ceftriaxone + sodium) = 90.17 mOsmol/L Ceftriaxone + 90.17 mOsmol/L sodium = 180.35 mOsmol/L
Need 280 = 280 - 180.35 = 99.65 mOslmol/L glycerol
(X g / 20 mL)(1000 mL / 1 L)(1 mol / 92.09 g)(1 Osmol / 1 mol)(1000 mOsmol / 1 Osmol) = 99.65 mOsmol/L
X = 0.1835 g = 183.5 mg
Which of the following is NOT relevant to the air quality of LAFW?
A. ISO class 100
B. Federal standard 209E Class 100
C. No more than 100 particles with a size > 0.5 micron per cubic foot
D. No more than 3520 particles with a size of > 0.5 micron per cubic meter
A. ISO class 100
Rationale: Should be ISO class 5
Which of the following is relevant to peripheral vascular access?
A. ADD-Vantage
B. PICC
C. Hickman
D. Broviac
E. Vascular access port
F. CVC
A. Add-Vantage
Rationale: All others are central access devices
The following structure is:
A. A block copolymer
B. A homopolymer
C. An alternate copolymer
D. A graft copolymer
E. A random copolymer
A. A block copolymer
Rationale: Block copolymers contain a chain of X following a chain of Y (X-X-Y-Y). Homopolymers contain one monomer (X-X-X-X). Alternate copolymers contain alternating X and Y (X-Y-X-Y). Graft copolymers contain a linear chain of X with branches of Y (X-X(Y-Y)-X-X(Y-Y)). Random copolymers contain X and Y in a random order (X-X-Y-X-Y-Y-Y-X-X).
The following reaction produces a polyester. What type of polymerization mechanism is the following?
A. Addition polymerization
B. Chain polymerization
C. Step polymerization
D. Propagation polymerization
E. None of the above
C. Step polymerization
Rationale: Step polymerization is when two or more (bifunctional) monomers carrying different reactive functional groups interact with each other. Addition polymerization is also called chain polymerization and has initiation, propagation, and termination steps. Propagation polymerization is not a thing.
mRNA therapeutics are commonly manufactured by:
A. Transcription in CHO host cells
B. Transcription in insect cells
C. Solid-supported chemical synthesis
D. Translation in CHO host cells
E. In-vitro transcription
E. In-vitro transcription
Rationale: Longer RNAs (mRNAs) are synthesized by transcription enzymes. In-vitro synthesis of RNA also works with modified nucleotides. Ex: COVID vaccine
Inclisiran, a therapeutic siRNA used to lower cholesterol levels, is modified with a trivalent GalNAc ligand at the 3’ end. What is the purpose of the GalNAc ligand?
A. To allow for room temperature storage of the siRNA
B. To enable binding of the siRNA to the mRNA of PCSK9 enzyme
C. To enhance protein production
D. To enable entry into the nucleus
E. To target the liver
E. To target the liver
Rationale: Liver targeting can be achieved with specific ligands, such as GalNAC) covalently attached to siRNA drugs.
Which of the following are major challenges for potential routes of delivery for peptide and protein drugs?
1. High variability of the bioavailability
2. Unpleasant side effects from permeation enhancers
3. The complexity of oral formulations of peptide drugs is often greater than parenteral formulations
A. 1 only
B. 2 only
C. 1 and 2, but not 3
D. 1, 2, and 3
E. 2 and 3, but not 1
D. 1, 2, and 3
Rationale: Peptide and protein drugs often have high variability of bioavailability and it is better to use drugs with a wide therapeutic index. Permeation enhancers can decrease tolerability and cause side effects. Peptide and protein drugs often have low oral bioavailability and they are more complex.
