Introduction to polymers in novel drug delivery MCQs With Answer

Introduction to polymers in novel drug delivery

Polymers are versatile macromolecules widely used in novel drug delivery systems to achieve targeted, sustained, and controlled release. B. Pharm students must understand types of polymers—natural and synthetic—along with biodegradable polymers like PLGA and PEGylated systems, mucoadhesive carriers such as chitosan, and smart stimuli-responsive hydrogels and micelles. Key concepts include polymer molecular weight, crystallinity, glass transition temperature, crosslinking, drug–polymer interactions, nanoparticle formulation methods, encapsulation efficiency, and release kinetics (diffusion, erosion, degradation). Clinical translation demands biocompatibility, sterilization stability, and regulatory awareness. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. What defines a polymer used in drug delivery?

• A small organic molecule with a single functional group
• A macromolecule composed of repeating monomer units
• An inorganic salt used as an excipient
• A monomeric drug precursor

Correct Answer: A macromolecule composed of repeating monomer units

Q2. Which property of a polymer most directly affects drug diffusion through a matrix?

• Color of the polymer
• Molecular weight and crosslink density
• Pungency
• Melting point only

Correct Answer: Molecular weight and crosslink density

Q3. PLGA is widely used in controlled release because it is:

• Non-biodegradable and highly crystalline
• Biodegradable and hydrolytically degradable
• Highly volatile
• Insoluble and non-degradable

Correct Answer: Biodegradable and hydrolytically degradable

Q4. PEGylation of therapeutic molecules primarily improves:

• Water repellency
• Solubility and circulation half-life
• Color stabilization
• Thermal conductivity

Correct Answer: Solubility and circulation half-life

Q5. Which polymer is known for mucoadhesive properties used in buccal delivery?

• Polyethylene (PE)
• Chitosan
• Polytetrafluoroethylene (PTFE)
• Polypropylene

Correct Answer: Chitosan

Q6. A hydrogel swells primarily due to:

• Hydrophobic interactions alone
• Crosslinking density and hydrophilic network uptake of water
• Evaporation of solvent
• Increase in crystalline domains

Correct Answer: Crosslinking density and hydrophilic network uptake of water

Q7. Which mechanism is NOT a common release mechanism from polymeric matrices?

• Diffusion-controlled release
• Erosion-controlled release
• Biodegradation-controlled release
• Photosynthesis-controlled release

Correct Answer: Photosynthesis-controlled release

Q8. Which analytical technique is commonly used to determine polymer molecular weight distribution?

• Gas chromatography (GC)
• Gel permeation chromatography (GPC)/size exclusion chromatography
• Flame photometry
• Atomic absorption spectroscopy

Correct Answer: Gel permeation chromatography (GPC)/size exclusion chromatography

Q9. In polymeric nanoparticles, ‘burst release’ refers to:

• A delayed onset of drug release after several days
• Rapid initial release of a large fraction of drug
• Complete absence of release
• Release triggered by magnetic fields only

Correct Answer: Rapid initial release of a large fraction of drug

Q10. Which statement about biodegradable polymers is true?

• They always degrade enzymatically only
• They can degrade hydrolytically or enzymatically into biocompatible products
• They are never used for implants
• They cannot be sterilized

Correct Answer: They can degrade hydrolytically or enzymatically into biocompatible products

Q11. Which synthetic polymer is a copolymer of lactic and glycolic acid used in drug delivery?

• Polyvinyl alcohol (PVA)
• Poly(lactic-co-glycolic acid) (PLGA)
• Polystyrene
• Polyethylene terephthalate (PET)

Correct Answer: Poly(lactic-co-glycolic acid) (PLGA)

Q12. Glass transition temperature (Tg) of a polymer influences:

• Drug chemical structure only
• Polymer chain mobility and release behavior at physiological temperature
• Only the optical properties
• Electrical conductivity only

Correct Answer: Polymer chain mobility and release behavior at physiological temperature

Q13. Which delivery system uses amphiphilic polymers to form a core–shell structure for hydrophobic drugs?

• Hydrogel bead
• Polymeric micelle
• Metallic nanoparticle
• Simple solution

Correct Answer: Polymeric micelle

Q14. Dendrimers are best described as:

• Linear high molecular weight polymers only
• Branched, monodisperse macromolecules with internal cavities
• Inorganic salts used to adjust pH
• Small molecule drugs

Correct Answer: Branched, monodisperse macromolecules with internal cavities

Q15. Encapsulation efficiency in nanoparticle preparation refers to:

• Percentage of polymer converted to monomer
• Percentage of initial drug actually entrapped in the carrier
• Number of steps in the manufacturing process
• Viscosity of the polymer solution

Correct Answer: Percentage of initial drug actually entrapped in the carrier

Q16. Which polymer is commonly used in ophthalmic controlled release formulations for its mucoadhesive and biocompatible nature?

• Carbopol (carbomer)
• Polyethylene (PE)
• Polyvinyl chloride (PVC)
• Polystyrene

Correct Answer: Carbopol (carbomer)

Q17. Stimuli-responsive polymers change their properties in response to:

• Only gravitational force
• Environmental triggers like pH, temperature, redox state
• Static color changes
• Time of day only

Correct Answer: Environmental triggers like pH, temperature, redox state

Q18. Emulsion solvent evaporation is a technique used to prepare:

• Polymeric nanoparticles and microparticles
• Simple syrup formulations
• Direct compression tablets without polymers
• Gas-phase monomers only

Correct Answer: Polymeric nanoparticles and microparticles

Q19. A higher degree of polymer crystallinity generally results in:

• Increased chain mobility and faster drug release
• Decreased permeability and slower drug release
• No change in mechanical properties
• Instant dissolution in water

Correct Answer: Decreased permeability and slower drug release

Q20. Which polymer is naturally derived and commonly used for wound dressings and drug delivery due to biodegradability?

• Chitosan
• Polystyrene
• Polyvinylidene fluoride (PVDF)
• Polypropylene

Correct Answer: Chitosan

Q21. Surface PEGylation of nanoparticles primarily reduces:

• Hydrophilicity
• Opsonic protein adsorption and RES uptake
• Mechanical strength
• Drug potency

Correct Answer: Opsonic protein adsorption and RES uptake

Q22. Which polymer characterization technique measures thermal transitions like Tg and melting point?

• UV-Vis spectroscopy
• Differential scanning calorimetry (DSC)
• High performance liquid chromatography (HPLC)
• Fourier-transform infrared spectroscopy (FTIR)

Correct Answer: Differential scanning calorimetry (DSC)

Q23. In matrix-controlled release, if release follows Higuchi kinetics, the primary mechanism is:

• Zero-order bulk erosion
• Diffusion from a homogeneous matrix
• Complete enzymatic cleavage
• Instantaneous release

Correct Answer: Diffusion from a homogeneous matrix

Q24. Which polymer is commonly used to form biodegradable sutures and implants?

• Polylactic acid (PLA)
• Polyethylene
• Polyvinyl chloride
• Polystyrene

Correct Answer: Polylactic acid (PLA)

Q25. Mucoadhesive strength of a polymer depends mainly on:

• Hydrogen bonding, electrostatic interactions, and polymer chain flexibility
• Color and odor of polymer
• Only polymer molecular weight regardless of functionality
• Magnetic properties

Correct Answer: Hydrogen bonding, electrostatic interactions, and polymer chain flexibility

Q26. Block copolymers forming nanoparticles for drug delivery typically self-assemble due to:

• Hydrophilic–hydrophobic balance of blocks
• Radioactive decay
• High ionic strength only
• Monomer volatility

Correct Answer: Hydrophilic–hydrophobic balance of blocks

Q27. Polymer–drug conjugates provide which advantage?

• Immediate renal clearance
• Improved solubility, targeted delivery, and controlled release
• Guaranteed lack of immunogenicity
• Permanent chemical bonding preventing release

Correct Answer: Improved solubility, targeted delivery, and controlled release

Q28. Which sterilization method can degrade some biodegradable polymers and must be validated?

• Gamma irradiation and high-temperature autoclaving
• Filtration through 0.22 µm for solid implants
• Sterilization by dilution only
• Storage at room temperature indefinitely

Correct Answer: Gamma irradiation and high-temperature autoclaving

Q29. Which factor increases encapsulation efficiency for hydrophobic drugs in polymer nanoparticles?

• Using a highly water-soluble polymer only
• Increasing polymer hydrophobicity and organic phase drug solubility
• Eliminating the polymer entirely
• Lowering drug–polymer affinity

Correct Answer: Increasing polymer hydrophobicity and organic phase drug solubility

Q30. Which regulatory consideration is critical for polymeric drug delivery systems?

• Color matching with packaging only
• Toxicity, biocompatibility, degradation products, and sterilization validation
• Ensuring polymers are never characterized
• Guaranteeing 100% non-degradability in vivo

Correct Answer: Toxicity, biocompatibility, degradation products, and sterilization validation

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com