Introduction:
Biotechnology in Drug Delivery MCQs With Answer provides M.Pharm students a focused review of contemporary biotechnological approaches applied to drug delivery. This resource emphasizes mechanisms, formulation strategies, delivery platforms (viral and non-viral), and translational challenges such as stability, immunogenicity and regulatory considerations. The questions are designed to test conceptual understanding and practical implications of using proteins, peptides, nucleic acids, antibodies, nanoparticles, and biologically-derived carriers to achieve targeted, sustained or intracellular delivery. Answers are given to aid self-assessment and revision for examinations in Novel Drug Delivery Systems, encouraging deeper learning and critical thinking about design choices in biopharmaceutical delivery.
Q1. Which property of PEGylation most directly contributes to prolonged systemic circulation of therapeutic proteins?
- Increased enzymatic activity
- Reduced renal filtration due to increased hydrodynamic radius
- Enhanced receptor-mediated uptake
- Improved acid stability in the stomach
Correct Answer: Reduced renal filtration due to increased hydrodynamic radius
Q2. Which viral vector is most commonly used for long-term stable gene expression in non-dividing cells?
- Adeno-associated virus (AAV)
- Retrovirus (gamma-retrovirus)
- Adenovirus
- Sendai virus
Correct Answer: Adeno-associated virus (AAV)
Q3. In antibody-drug conjugates (ADCs), what is the primary function of the linker?
- Enhance antibody affinity for target antigen
- Control release of the cytotoxic payload at or inside target cells
- Increase solubility of the payload in plasma
- Reduce ADC molecular weight for better tissue penetration
Correct Answer: Control release of the cytotoxic payload at or inside target cells
Q4. Which characteristic is most critical when designing lipid nanoparticles (LNPs) for siRNA delivery to hepatocytes?
- Positively charged surface at physiological pH
- Inclusion of a hepatocyte-targeting ligand such as GalNAc
- High content of cholesterol to avoid endosomal escape
- Large particle size (>500 nm) for improved circulation
Correct Answer: Inclusion of a hepatocyte-targeting ligand such as GalNAc
Q5. Exosomes as drug delivery vehicles offer which main advantage over synthetic nanoparticles?
- Unlimited manufacturing scalability
- Intrinsic biocompatibility and native cell-targeting signals
- Higher drug loading capacity than liposomes
- Elimination of immunogenicity in all patients
Correct Answer: Intrinsic biocompatibility and native cell-targeting signals
Q6. Which non-viral vector is commonly used for plasmid DNA delivery due to branched architecture and surface amines?
- Dendrimer (e.g., PAMAM)
- Gold nanoparticles
- Hydrogel microparticles
- Polysorbate micelles
Correct Answer: Dendrimer (e.g., PAMAM)
Q7. What is the major challenge when delivering therapeutic proteins orally?
- Excessive bioavailability due to transcytosis
- Proteolytic degradation and poor intestinal absorption
- Rapid renal reabsorption
- Overstimulation of hepatocyte metabolism
Correct Answer: Proteolytic degradation and poor intestinal absorption
Q8. Which mechanism primarily enables targeted intracellular delivery of nanoparticles via receptor-mediated endocytosis?
- Diffusion through nuclear pores
- Ligand binding to cell surface receptors triggering endocytosis
- Passive paracellular transport across tight junctions
- Transient membrane poration due to shear stress
Correct Answer: Ligand binding to cell surface receptors triggering endocytosis
Q9. What is the principal advantage of Fc-fusion proteins in therapeutic delivery?
- Decreased molecular weight for tissue penetration
- Reduced binding to neonatal Fc receptor (FcRn)
- Prolonged half-life via FcRn-mediated recycling
- Increased enzymatic activity of the fused protein
Correct Answer: Prolonged half-life via FcRn-mediated recycling
Q10. For CRISPR-Cas9 genome editing in vivo, which delivery modality balances efficient editing and low immunogenicity for many applications?
- Adenoviral vectors
- Non-viral lipid nanoparticles delivering mRNA and gRNA
- Plasmid DNA with electroporation in situ
- Baculoviral vectors
Correct Answer: Non-viral lipid nanoparticles delivering mRNA and gRNA
Q11. Which factor most increases immunogenicity risk of therapeutic proteins delivered repeatedly?
- Glycosylation identical to human pattern
- Presence of aggregates and impurities
- PEGylation at low PEG density
- Administration via intravenous infusion
Correct Answer: Presence of aggregates and impurities
Q12. Aptamers used in targeted drug delivery are best described as:
- Small peptides that penetrate cell membranes
- Nucleic acid ligands that bind targets with high affinity and specificity
- Polysaccharide carriers for sustained release
- Hydrophobic polymers for depot formation
Correct Answer: Nucleic acid ligands that bind targets with high affinity and specificity
Q13. Which modification can reduce proteolytic degradation of therapeutic peptides when designing delivery systems?
- Incorporating L-amino acids exclusively
- Appending a short hydrophobic tag to increase aggregation
- Substitution with D-amino acids or cyclization
- Increasing sequence length beyond 500 amino acids
Correct Answer: Substitution with D-amino acids or cyclization
Q14. What is the common purpose of using targeting ligands (antibodies, peptides, sugars) on nanoparticle surfaces?
- To increase particle size for slower clearance
- To promote selective binding and uptake by target cells/tissues
- To neutralize inflammatory cytokines systemically
- To enhance chemical stability during storage
Correct Answer: To promote selective binding and uptake by target cells/tissues
Q15. Which statement about PEGylation and immunogenicity is most accurate?
- PEGylation universally eliminates immunogenicity of biologics
- Anti-PEG antibodies can develop and accelerate clearance for some products
- PEG increases T-cell epitope presentation and boosts immune response
- PEGylation increases protease susceptibility
Correct Answer: Anti-PEG antibodies can develop and accelerate clearance for some products
Q16. In formulating protein-loaded nanoparticles, what role does lyophilization with cryoprotectants play?
- It enhances protease activity during storage
- It stabilizes structure and prevents aggregation during drying and storage
- It increases particle size to >1 µm for depot effects
- It selectively removes glycosylation from proteins
Correct Answer: It stabilizes structure and prevents aggregation during drying and storage
Q17. Which regulatory concern is unique to biologic drug delivery systems compared with small molecules?
- Need to assess stereoisomerism
- Characterization of higher-order structure and batch-to-batch variability
- Identification of synthetic pathway impurities only
- Requirement for simple dissolution testing
Correct Answer: Characterization of higher-order structure and batch-to-batch variability
Q18. Bispecific antibodies in targeted delivery are engineered primarily to:
- Bind two epitopes on the same antigen only
- Simultaneously engage a target cell antigen and an effector cell receptor
- Increase metabolic clearance through dual recognition
- Serve as enzyme mimetics for prodrug activation
Correct Answer: Simultaneously engage a target cell antigen and an effector cell receptor
Q19. Which characteristic of polymeric microsphere formulations is most important for achieving controlled release of protein therapeutics?
- Polymer glass transition temperature only
- Polymer degradation rate and protein–polymer interactions
- Use of only hydrophilic polymers to accelerate release
- Elimination of all excipients to avoid interaction
Correct Answer: Polymer degradation rate and protein–polymer interactions
Q20. Which delivery approach is most appropriate for targeted, transient delivery of mRNA vaccines to antigen-presenting cells?
- Intramuscular injection of naked plasmid DNA
- Lipid nanoparticle encapsulation of mRNA for intramuscular or intradermal injection
- Oral administration of mRNA-loaded microparticles
- Administration of mRNA complexed with high molecular weight PEG alone
Correct Answer: Lipid nanoparticle encapsulation of mRNA for intramuscular or intradermal injection

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
