Q.1 Which of the following nanocarriers is primarily composed of phospholipid bilayers?
Polymeric nanoparticles
Liposomes
Dendrimers
Metallic nanoparticles
Explanation - Liposomes consist of one or more phospholipid bilayers surrounding an aqueous core, mimicking cell membranes.
Correct answer is: Liposomes
Q.2 Iontophoresis enhances drug delivery across the skin by using which of the following mechanisms?
Magnetic fields
Electrical current
Ultrasound waves
Thermal gradients
Explanation - Iontophoresis uses a low-level electric current to drive charged drug molecules through the skin.
Correct answer is: Electrical current
Q.3 Which stimulus‑responsive polymer expands in response to a rise in temperature, making it useful for controlled drug release?
Polyethylene glycol
Poly(N‑isopropylacrylamide)
Polylactic acid
Polyvinyl alcohol
Explanation - PNIPAM exhibits a lower critical solution temperature (~32 °C) and becomes hydrophobic above this, causing it to shrink and release its payload.
Correct answer is: Poly(N‑isopropylacrylamide)
Q.4 In an electro‑responsive drug delivery system, the release of the drug is triggered by:
pH change
Magnetic field
Electrical stimulus
Enzymatic degradation
Explanation - Electro‑responsive systems release drugs when an external voltage changes the carrier's permeability or structure.
Correct answer is: Electrical stimulus
Q.5 Which of the following is a key advantage of using dendrimers for targeted drug delivery?
Large size allowing slow diffusion
Highly branched architecture enabling multivalent surface functionalization
Inherent magnetic properties
Intrinsic fluorescence
Explanation - Dendrimers have a defined, highly branched structure that allows attachment of multiple targeting ligands or drugs on their surface.
Correct answer is: Highly branched architecture enabling multivalent surface functionalization
Q.6 What is the primary purpose of attaching folic acid to a nanoparticle drug carrier?
To increase particle size
To target cancer cells overexpressing folate receptors
To improve solubility in water
To make the carrier magnetic
Explanation - Folic acid binds to folate receptors, which are often overexpressed on cancer cells, enabling receptor‑mediated endocytosis of the carrier.
Correct answer is: To target cancer cells overexpressing folate receptors
Q.7 Which method is commonly used to fabricate polymeric nanoparticles for drug delivery?
Emulsion‑solvent evaporation
Physical vapor deposition
Molecular beam epitaxy
Laser ablation
Explanation - The emulsion‑solvent evaporation technique creates nanoparticles by emulsifying a polymer solution in an aqueous phase followed by solvent removal.
Correct answer is: Emulsion‑solvent evaporation
Q.8 A drug‑loaded hydrogel that swells in response to glucose concentration is an example of:
pH‑responsive system
Thermo‑responsive system
Enzyme‑responsive system
Glucose‑responsive system
Explanation - Glucose‑responsive hydrogels contain phenylboronic acid groups that bind glucose, causing swelling and drug release.
Correct answer is: Glucose‑responsive system
Q.9 What is the main advantage of using magnetic nanoparticles for targeted drug delivery?
They can be heated by external magnetic fields for controlled release
They are biodegradable without any modification
They release drugs only in acidic environments
They naturally accumulate in the liver
Explanation - Magnetic nanoparticles can be guided to a specific site and heated by an alternating magnetic field, triggering drug release (magnetic hyperthermia).
Correct answer is: They can be heated by external magnetic fields for controlled release
Q.10 Which of the following best describes the Enhanced Permeability and Retention (EPR) effect?
Increased drug diffusion through tight junctions
Selective accumulation of nanosized carriers in tumor tissue due to leaky vasculature
Improved renal clearance of small molecules
Active transport of drugs across the blood‑brain barrier
Explanation - The EPR effect allows nanoparticles (typically 10‑200 nm) to passively accumulate in tumor tissue where vasculature is fenestrated.
Correct answer is: Selective accumulation of nanosized carriers in tumor tissue due to leaky vasculature
Q.11 Electroporation facilitates drug delivery by:
Creating temporary pores in cell membranes using electrical pulses
Increasing temperature of the tissue
Generating ultrasonic waves
Changing the pH of the extracellular environment
Explanation - Electroporation applies short high-voltage pulses that destabilize the lipid bilayer, forming transient pores through which molecules can enter cells.
Correct answer is: Creating temporary pores in cell membranes using electrical pulses
Q.12 Which material is commonly used for constructing biodegradable polymeric micelles for drug delivery?
Polystyrene
Poly(lactic‑co‑glycolic acid) (PLGA)
Silicon dioxide
Gold
Explanation - PLGA is FDA‑approved, biodegradable, and forms amphiphilic block copolymers that self‑assemble into micelles.
Correct answer is: Poly(lactic‑co‑glycolic acid) (PLGA)
Q.13 A drug delivery system that releases its payload only after exposure to a specific enzyme is known as:
pH‑responsive
Enzyme‑responsive
Thermo‑responsive
Magnetically‑responsive
Explanation - Enzyme‑responsive carriers contain linkers cleavable by target enzymes, ensuring release at disease sites where those enzymes are overexpressed.
Correct answer is: Enzyme‑responsive
Q.14 What is the main purpose of PEGylation of nanoparticle drug carriers?
To increase electrical conductivity
To improve biocompatibility and prolong circulation time
To make the particles magnetic
To induce rapid cellular uptake
Explanation - PEG creates a hydrophilic stealth layer that reduces protein adsorption and recognition by the mononuclear phagocyte system.
Correct answer is: To improve biocompatibility and prolong circulation time
Q.15 Which technique is used to measure the zeta potential of nanoparticles?
Dynamic light scattering (DLS)
Scanning electron microscopy (SEM)
Nuclear magnetic resonance (NMR)
Electrophoretic light scattering (ELS)
Explanation - ELS determines the velocity of particles under an electric field, from which zeta potential is calculated.
Correct answer is: Electrophoretic light scattering (ELS)
Q.16 In a pH‑responsive drug delivery system, the drug is released when:
The temperature rises above 40 °C
The surrounding pH changes to acidic or basic conditions
A magnetic field is applied
Ultrasound waves are emitted
Explanation - pH‑responsive carriers contain acid‑labile bonds or polymers that swell or degrade at specific pH values, releasing the drug.
Correct answer is: The surrounding pH changes to acidic or basic conditions
Q.17 Which of the following is a limitation of using liposomes for drug delivery?
Inability to encapsulate hydrophilic drugs
Rapid clearance by the reticuloendothelial system (RES)
High electrical conductivity
Intrinsic magnetic properties
Explanation - Unmodified liposomes are quickly recognized and removed by RES; surface modification (e.g., PEGylation) is required to extend circulation.
Correct answer is: Rapid clearance by the reticuloendothelial system (RES)
Q.18 Which of the following drugs is commonly delivered using a transdermal iontophoretic patch?
Insulin
Aspirin
Diazepam
Nitroglycerin
Explanation - Iontophoretic patches can deliver charged macromolecules like insulin across the skin without needles.
Correct answer is: Insulin
Q.19 The term 'nanocarrier' refers to:
A device that generates nanowatts of power
A vehicle at the nanoscale designed to transport therapeutic agents
A type of semiconductor chip
A miniature robotic surgeon
Explanation - Nanocarriers are nanoscale structures (e.g., liposomes, polymeric nanoparticles) engineered to encapsulate and deliver drugs.
Correct answer is: A vehicle at the nanoscale designed to transport therapeutic agents
Q.20 Which of the following best describes a 'prodrug' strategy in targeted delivery?
A drug that becomes active only after metabolic conversion at the target site
A drug that is electrically charged for iontophoresis
A drug that fluoresces under UV light
A drug that is encapsulated in a metallic shell
Explanation - Prodrugs are inactive precursors that are enzymatically or chemically transformed into the active drug at the intended location.
Correct answer is: A drug that becomes active only after metabolic conversion at the target site
Q.21 Which parameter most directly influences the ability of nanoparticles to cross the blood‑brain barrier (BBB)?
Particle charge
Particle size
Magnetic susceptibility
Optical density
Explanation - Nanoparticles smaller than ~100 nm can more readily cross the BBB via transcytosis, especially when surface-modified with targeting ligands.
Correct answer is: Particle size
Q.22 A stimulus‑responsive hydrogel that degrades under ultraviolet (UV) light is an example of:
Thermo‑responsive
Photodegradable
pH‑responsive
Magnetically‑responsive
Explanation - Photodegradable hydrogels contain light‑cleavable bonds that break upon UV exposure, releasing the encapsulated drug.
Correct answer is: Photodegradable
Q.23 In electroporation, the term 'reversible electroporation' means:
Cell membranes are permanently destroyed
Pores reseal after the pulse, allowing cell survival
The electric field is continuously applied
Only non‑living cells are affected
Explanation - Reversible electroporation creates temporary pores that close after a short time, enabling drug entry without killing the cell.
Correct answer is: Pores reseal after the pulse, allowing cell survival
Q.24 Which of the following is an advantage of using polymeric micelles over conventional surfactants for drug solubilization?
Higher toxicity
Greater stability in the bloodstream
Lower drug loading capacity
Inability to target specific tissues
Explanation - Polymeric micelles have a core‑shell structure that is more stable against dilution and serum proteins compared with simple surfactant micelles.
Correct answer is: Greater stability in the bloodstream
Q.25 Which analytical technique is most suitable for determining the drug loading efficiency of a nanoparticle formulation?
UV‑Vis spectroscopy
Fourier‑transform infrared (FTIR) spectroscopy
X‑ray diffraction (XRD)
Atomic force microscopy (AFM)
Explanation - UV‑Vis can quantify the amount of drug released from a known amount of carrier, allowing calculation of loading efficiency.
Correct answer is: UV‑Vis spectroscopy
Q.26 A nanocarrier functionalized with the peptide RGD is intended to target:
Glucose transporters
Integrin receptors on angiogenic endothelial cells
Dopamine receptors
GABA receptors
Explanation - The RGD peptide binds to αvβ3 and αvβ5 integrins, which are overexpressed in angiogenic vasculature of tumors.
Correct answer is: Integrin receptors on angiogenic endothelial cells
Q.27 Which of the following best describes the term 'active targeting' in drug delivery?
Delivery driven solely by diffusion
Use of external magnetic fields to guide carriers
Attachment of ligands that bind to specific receptors on target cells
Encapsulation of drug in a pH‑sensitive polymer
Explanation - Active targeting employs surface ligands (antibodies, peptides, aptamers) to recognize and bind target cell receptors, improving specificity.
Correct answer is: Attachment of ligands that bind to specific receptors on target cells
Q.28 The term 'theranostics' in nanomedicine refers to:
Thermal ablation devices
Combined therapy and diagnostic capabilities in a single platform
Thermal sensors for temperature monitoring
Thermal insulation materials
Explanation - Theranostic nanoparticles simultaneously deliver drugs and provide imaging contrast (e.g., MRI, fluorescence).
Correct answer is: Combined therapy and diagnostic capabilities in a single platform
Q.29 Which of the following is a common method to functionalize the surface of silica nanoparticles with targeting ligands?
Silane coupling chemistry
Electroplating
Sputtering
Ion implantation
Explanation - Organosilanes (e.g., APTES) react with surface silanol groups, providing functional groups for ligand attachment.
Correct answer is: Silane coupling chemistry
Q.30 A drug delivery system that releases its payload when exposed to a magnetic field is primarily utilizing:
Magnetically‑induced heating (magnetic hyperthermia)
Magnetic alignment for transport
Magnetic resonance imaging
Electromagnetic shielding
Explanation - Alternating magnetic fields cause superparamagnetic nanoparticles to generate heat, which can trigger drug release from thermosensitive carriers.
Correct answer is: Magnetically‑induced heating (magnetic hyperthermia)
Q.31 Which characteristic of a nanocarrier most directly influences its renal clearance?
Surface charge
Particle size below ~5‑6 nm
Magnetic susceptibility
Optical properties
Explanation - Renal filtration efficiently removes particles smaller than the glomerular filtration threshold (~5‑6 nm).
Correct answer is: Particle size below ~5‑6 nm
Q.32 What is the role of a 'cleavable linker' in antibody‑drug conjugates (ADCs)?
To increase the molecular weight of the ADC
To enable drug release after internalization into target cells
To provide fluorescence for imaging
To make the ADC magnetic
Explanation - Cleavable linkers are designed to be broken by intracellular enzymes or low pH, releasing the cytotoxic payload inside the target cell.
Correct answer is: To enable drug release after internalization into target cells
Q.33 Which of the following is a major challenge when delivering nucleic acids (e.g., siRNA) using nanocarriers?
Low electrical conductivity
Rapid degradation by nucleases
Inability to cross the skin
Excessive magnetic susceptibility
Explanation - siRNA is vulnerable to enzymatic degradation; nanocarriers protect it and facilitate cellular uptake.
Correct answer is: Rapid degradation by nucleases
Q.34 The term 'biocompatibility' in the context of drug delivery systems means:
The carrier conducts electricity well
The carrier does not induce adverse immune responses or toxicity
The carrier is magnetic
The carrier can be visualized under X‑ray
Explanation - Biocompatibility denotes that the material is safe and does not provoke harmful biological reactions.
Correct answer is: The carrier does not induce adverse immune responses or toxicity
Q.35 Which polymer is known for its pH‑sensitive solubility, being soluble at low pH and precipitating at neutral pH?
Poly(lactic acid)
Poly(ethylene glycol)
Poly(methacrylic acid)
Polystyrene
Explanation - Poly(methacrylic acid) ionizes at low pH, becoming soluble, and de‑ionizes at neutral pH, leading to precipitation.
Correct answer is: Poly(methacrylic acid)
Q.36 In a drug delivery system, 'burst release' refers to:
A rapid initial release of a large fraction of the drug
A release that occurs only under magnetic fields
A continuous slow release over weeks
A release triggered by temperature drop
Explanation - Burst release is an undesired phenomenon where a significant amount of drug is released immediately upon administration.
Correct answer is: A rapid initial release of a large fraction of the drug
Q.37 Which of the following is an example of a 'smart' drug delivery system?
A tablet that dissolves in water
A nanoparticle that releases drug in response to tumor‑specific enzymes
A syringe
A static polymer matrix
Explanation - Smart systems respond to internal (e.g., enzymes) or external (e.g., light) triggers to release the drug on demand.
Correct answer is: A nanoparticle that releases drug in response to tumor‑specific enzymes
Q.38 Which factor most directly influences the circulation half‑life of a nanoparticle in blood?
Particle color
Surface hydrophilicity
Magnetic moment
Electrical resistance
Explanation - Hydrophilic surfaces (e.g., PEGylation) reduce opsonization, thereby extending circulation time.
Correct answer is: Surface hydrophilicity
Q.39 Which of the following is NOT a common route for targeted drug delivery?
Intravenous injection
Oral administration
Transdermal iontophoresis
Inhalation of gases
Explanation - While inhalation of aerosols is common, inhalation of gases is not a standard targeted delivery route for nanocarriers.
Correct answer is: Inhalation of gases
Q.40 The main purpose of using a 'core‑shell' architecture in nanocarriers is to:
Increase electrical conductivity
Separate hydrophobic drug core from hydrophilic shell for stability
Make the particle magnetic
Enable optical imaging
Explanation - Core‑shell structures protect the drug (often hydrophobic) inside the core while the shell provides steric stability and stealth.
Correct answer is: Separate hydrophobic drug core from hydrophilic shell for stability
Q.41 Which of the following is a hallmark of an ideal targeted drug delivery system?
Low specificity, high systemic exposure
High specificity, low systemic toxicity
Rapid clearance from the body
Large particle size (>1 µm)
Explanation - Ideal systems deliver drugs precisely to diseased tissue while minimizing side effects elsewhere.
Correct answer is: High specificity, low systemic toxicity
Q.42 Which type of nanocarrier can be made electrically conductive to enable electrically controlled drug release?
Conductive polymer nanofibers
Silica nanoparticles
Gold nanorods
Lipid‑based liposomes
Explanation - Conductive polymers (e.g., polypyrrole) can change their oxidation state under voltage, opening pores for drug release.
Correct answer is: Conductive polymer nanofibers
Q.43 Which of the following is an advantage of using microfluidic platforms to produce nanoparticles?
Higher batch‑to‑batch variability
Precise control over particle size and distribution
Requires high temperature
Only produces micron‑scale particles
Explanation - Microfluidics allows laminar flow and rapid mixing, yielding uniform nanoparticles with tunable dimensions.
Correct answer is: Precise control over particle size and distribution
Q.44 A 'dual‑responsive' nanoparticle that reacts to both pH and temperature is designed to:
Release drug only at a specific pH and temperature combination found in tumors
Become magnetic in the bloodstream
Change color under UV light
Generate electrical currents
Explanation - Dual‑responsive systems provide higher specificity by requiring two physiological triggers typical of diseased tissue.
Correct answer is: Release drug only at a specific pH and temperature combination found in tumors
Q.45 Which of the following is a common method to evaluate the in‑vitro cytotoxicity of a new nanocarrier?
MTT assay
X‑ray diffraction
Fourier‑transform infrared spectroscopy
Scanning electron microscopy
Explanation - MTT measures metabolic activity of cells, indicating viability after exposure to the nanocarrier.
Correct answer is: MTT assay
Q.46 In the context of drug delivery, 'passive targeting' primarily relies on:
Ligand–receptor interactions
External magnetic fields
Physiological differences such as leaky vasculature
Electrical stimulation
Explanation - Passive targeting exploits the EPR effect and other physiological variations without active ligands.
Correct answer is: Physiological differences such as leaky vasculature
Q.47 Which of the following techniques is most suitable for visualizing the morphology of nanocarriers at the nanoscale?
Transmission electron microscopy (TEM)
Optical microscopy
Confocal laser scanning microscopy
Magnetic resonance imaging (MRI)
Explanation - TEM provides high‑resolution images (<1 nm) allowing direct observation of nanoparticle shape and size.
Correct answer is: Transmission electron microscopy (TEM)
Q.48 A nanocarrier designed to release drug upon encountering high concentrations of hydrogen peroxide (H₂O₂) is an example of:
pH‑responsive
Redox‑responsive
Thermo‑responsive
Magnetically‑responsive
Explanation - Redox‑responsive carriers contain H₂O₂‑cleavable linkers that degrade in oxidative environments such as inflamed or tumor tissue.
Correct answer is: Redox‑responsive
Q.49 Which property of a drug molecule most influences its encapsulation efficiency in liposomes?
Molecular weight
Hydrophilicity
Magnetic susceptibility
Electrical conductivity
Explanation - Hydrophilic drugs are encapsulated in the aqueous core, while hydrophobic drugs partition into the lipid bilayer; the compatibility determines efficiency.
Correct answer is: Hydrophilicity
Q.50 Which of the following is a common trigger for drug release from ultrasound‑responsive nanocarriers?
Mechanical cavitation
Magnetic field alignment
Electrical current
pH change
Explanation - Ultrasound causes cavitation bubbles that disrupt carrier structure, releasing the drug.
Correct answer is: Mechanical cavitation
Q.51 The term 'pharmacokinetics' refers to:
The study of drug–target interactions
The study of drug absorption, distribution, metabolism, and excretion
The mechanical properties of drug tablets
The electrical conductivity of drug solutions
Explanation - Pharmacokinetics describes how the body affects a drug over time.
Correct answer is: The study of drug absorption, distribution, metabolism, and excretion
Q.52 In a polymer‑based nanoparticle, the glass transition temperature (Tg) is important because:
It determines the magnetic properties
It affects the polymer's mechanical flexibility and drug release rate
It changes the particle color
It controls the electrical resistance
Explanation - Above Tg, the polymer becomes more flexible, often leading to faster drug diffusion.
Correct answer is: It affects the polymer's mechanical flexibility and drug release rate
Q.53 Which of the following is a key reason for using biodegradable polymers in drug delivery?
To increase long‑term accumulation in organs
To allow the carrier to break down into non‑toxic by‑products after drug release
To make the carrier electrically conductive
To provide magnetic resonance contrast
Explanation - Biodegradable polymers (e.g., PLGA) degrade into safe monomers, minimizing long‑term toxicity.
Correct answer is: To allow the carrier to break down into non‑toxic by‑products after drug release
Q.54 A nanocarrier that releases drug when exposed to a specific wavelength of light is known as:
Photodynamic
Photothermal
Photocleavable
Photoluminescent
Explanation - Photocleavable linkers break upon irradiation, allowing controlled release of the drug.
Correct answer is: Photocleavable
Q.55 Which of the following best describes the role of 'surface charge' in nanoparticle biodistribution?
Neutral particles are cleared fastest by the liver
Positively charged particles often show higher cellular uptake but faster clearance
Negatively charged particles cannot cross blood vessels
Surface charge does not affect biodistribution
Explanation - Positive charge enhances interaction with negatively charged cell membranes but also leads to opsonization and rapid RES clearance.
Correct answer is: Positively charged particles often show higher cellular uptake but faster clearance
Q.56 Which of the following is NOT a typical component of a liposomal drug formulation?
Phospholipids
Cholesterol
Polyethylene glycol (PEG)
Silicon dioxide
Explanation - Silicon dioxide is not a standard component of liposomes; it is used in other nanoparticle systems.
Correct answer is: Silicon dioxide
Q.57 A major advantage of using 'nanosponges' for drug delivery is:
They are magnetic by nature
They provide a large internal surface area for high drug loading
They emit fluorescence without labeling
They are electrically conductive
Explanation - Nanosponges are porous, cross‑linked polymeric networks that can encapsulate high amounts of drug molecules.
Correct answer is: They provide a large internal surface area for high drug loading
Q.58 The term 'bio‑adhesive' in drug delivery refers to:
A carrier that adheres to biological surfaces (e.g., mucosa) to prolong residence time
A magnetic nanoparticle
A fluorescent probe
A high‑temperature resistant polymer
Explanation - Bio‑adhesive formulations stick to tissues, enhancing drug absorption and reducing dosing frequency.
Correct answer is: A carrier that adheres to biological surfaces (e.g., mucosa) to prolong residence time
Q.59 Which of the following statements about 'targeted liposomes' is true?
They cannot be PEGylated
They are always larger than 500 nm
They can be functionalized with antibodies for active targeting
They release drug only at pH 7.4
Explanation - Antibody‑conjugated liposomes can specifically bind to antigens expressed on target cells.
Correct answer is: They can be functionalized with antibodies for active targeting
Q.60 In a 'nanogel', the drug is primarily:
Covalently bound to a metal core
Encapsulated within a cross‑linked polymer network that can swell
Suspended in an oil phase
Attached to a silica shell
Explanation - Nanogels are hydrogel nanoparticles that can absorb water and release drugs via swelling/de‑swelling.
Correct answer is: Encapsulated within a cross‑linked polymer network that can swell
Q.61 Which of the following is a common method to achieve 'site‑specific' drug release in the gastrointestinal (GI) tract?
Enteric coating that dissolves at higher pH of the intestine
Magnetic guidance
Ultrasound activation
Electrical stimulation
Explanation - Enteric coatings protect the drug in the acidic stomach and release it when reaching the higher pH of the intestine.
Correct answer is: Enteric coating that dissolves at higher pH of the intestine
Q.62 The 'critical micelle concentration' (CMC) is important because:
It determines the magnetic field strength needed for release
It is the concentration above which amphiphilic molecules self‑assemble into micelles
It defines the electrical conductivity of a solution
It sets the temperature at which polymers melt
Explanation - CMC is the threshold concentration for micelle formation; below it, micelles dissociate, leading to drug release.
Correct answer is: It is the concentration above which amphiphilic molecules self‑assemble into micelles
Q.63 A major safety concern associated with the use of carbon nanotubes (CNTs) in drug delivery is:
Their high electrical conductivity
Potential pulmonary toxicity and biopersistence
Their magnetic properties
Their bright fluorescence
Explanation - CNTs can cause inflammation and are difficult to clear from the body, raising safety issues.
Correct answer is: Potential pulmonary toxicity and biopersistence
Q.64 Which of the following nanocarriers is most suitable for delivering hydrophobic anticancer drugs like paclitaxel?
Polymeric micelles
Liposomes with large aqueous core
Hydrogel beads
Silica gel tablets
Explanation - Hydrophobic drugs partition into the micelle core, enhancing solubility and stability.
Correct answer is: Polymeric micelles
Q.65 The concept of 'controlled release' in drug delivery aims to:
Deliver the entire dose at once
Release the drug at a predetermined rate over a specific period
Make the drug invisible to the immune system
Change the drug’s chemical structure
Explanation - Controlled release systems modulate drug concentration to maintain therapeutic levels while reducing side effects.
Correct answer is: Release the drug at a predetermined rate over a specific period
Q.66 Which of the following is a common method to load a drug into polymeric nanoparticles?
Solvent evaporation
Laser ablation
Mechanical milling
Electroplating
Explanation - The solvent evaporation (or nanoprecipitation) method allows drug encapsulation during polymer solidification.
Correct answer is: Solvent evaporation
Q.67 In the context of drug delivery, the term 'bioavailability' refers to:
The proportion of administered drug that reaches systemic circulation in an active form
The magnetic strength of a carrier
The electrical voltage required to release the drug
The fluorescence intensity of a nanoparticle
Explanation - Bioavailability measures the fraction of an administered dose that becomes available at the site of action.
Correct answer is: The proportion of administered drug that reaches systemic circulation in an active form
Q.68 Which of the following strategies can be employed to reduce the immunogenicity of protein‑based drug carriers?
Increasing particle size to >5 µm
PEGylation of the protein surface
Adding a magnetic core
Using a highly charged surface
Explanation - PEGylation creates a steric shield that masks immunogenic epitopes, reducing immune recognition.
Correct answer is: PEGylation of the protein surface
Q.69 A nanocarrier designed to release drug in response to a decrease in pH (acidic environment) typically utilizes:
Acid‑labile linkers such as hydrazone bonds
Thermal‑sensitive polymers
Magnetic particles
Enzyme‑cleavable peptides
Explanation - Hydrazone bonds are stable at neutral pH but hydrolyze in acidic conditions, enabling pH‑triggered release.
Correct answer is: Acid‑labile linkers such as hydrazone bonds
Q.70 Which of the following is a primary benefit of using 'micro‑bubbles' in combination with ultrasound for drug delivery?
They generate heat to melt the drug
They enhance cavitation, facilitating drug penetration into tissues
They increase magnetic resonance signal
They provide electrical stimulation
Explanation - Micro‑bubbles oscillate under ultrasound, producing cavitation that temporarily disrupts cell membranes, enhancing drug uptake.
Correct answer is: They enhance cavitation, facilitating drug penetration into tissues
Q.71 In the design of a nanocarrier for ocular drug delivery, an important consideration is:
Particle size < 200 nm to penetrate corneal epithelium
Strong magnetic properties
High electrical conductivity
Fluorescent emission
Explanation - Small nanoparticles can traverse the tight junctions of the corneal epithelium, enhancing drug delivery to the eye.
Correct answer is: Particle size < 200 nm to penetrate corneal epithelium
Q.72 The main purpose of adding cholesterol to liposomal formulations is to:
Increase membrane fluidity and stability
Make the liposome magnetic
Provide fluorescent tagging
Render the liposome electrically conductive
Explanation - Cholesterol intercalates between phospholipids, reducing permeability and preventing premature leakage.
Correct answer is: Increase membrane fluidity and stability
Q.73 Which of the following is a typical characteristic of a 'nanoparticle'?
Diameter between 1 µm and 10 µm
Diameter between 1 nm and 100 nm
Diameter larger than 1 mm
Diameter exactly 500 nm
Explanation - Nanoparticles are generally defined as particles with at least one dimension in the 1‑100 nm range.
Correct answer is: Diameter between 1 nm and 100 nm
Q.74 Which of the following is NOT a typical trigger for a 'stimuli‑responsive' drug delivery system?
pH
Temperature
Magnetic field
Gravitational force
Explanation - Stimuli‑responsive systems exploit pH, temperature, light, magnetic fields, ultrasound, etc., not gravity.
Correct answer is: Gravitational force
Q.75 A 'targeted polymeric nanoparticle' that carries a chemotherapeutic drug and an MRI contrast agent is an example of:
Theranostic platform
Pure drug carrier
Magnetic hyperthermia device
pH‑sensitive hydrogel
Explanation - Combining therapy (drug) and diagnostics (contrast agent) defines a theranostic system.
Correct answer is: Theranostic platform
Q.76 In a microfluidic synthesis of liposomes, the primary advantage over bulk methods is:
Higher temperature tolerance
Better control over size distribution and reproducibility
Reduced need for phospholipids
Increased magnetic properties
Explanation - Microfluidic devices enable rapid mixing under laminar flow, yielding uniform liposomes with precise size control.
Correct answer is: Better control over size distribution and reproducibility
Q.77 Which of the following best describes the 'burst effect' in drug‑loaded polymeric nanoparticles?
Complete absence of drug release
Rapid release of a large fraction of drug immediately after administration
Slow, linear release over months
Release only after exposure to UV light
Explanation - Burst effect is often undesired as it can lead to toxicity; it occurs due to drug adsorbed on the surface.
Correct answer is: Rapid release of a large fraction of drug immediately after administration
Q.78 Which analytical method is most appropriate for quantifying the drug release profile of a nanoparticle formulation in vitro?
High‑performance liquid chromatography (HPLC)
Scanning electron microscopy (SEM)
X‑ray diffraction (XRD)
Atomic force microscopy (AFM)
Explanation - HPLC can accurately measure drug concentration in release media over time.
Correct answer is: High‑performance liquid chromatography (HPLC)
Q.79 In a drug delivery context, 'PEGylation' primarily serves to:
Increase the magnetic susceptibility of carriers
Provide a hydrophilic stealth layer that reduces opsonization
Make the carrier fluorescent
Induce rapid degradation
Explanation - PEG chains create a hydrated shell, decreasing protein binding and prolonging circulation.
Correct answer is: Provide a hydrophilic stealth layer that reduces opsonization
Q.80 Which of the following is a common method to achieve 'magnetic targeting' of drug‑loaded nanoparticles?
Applying an external static magnetic field to guide magnetic nanoparticles to the target site
Using ultrasound waves
Changing the pH of the surrounding tissue
Applying a high‑frequency electric field
Explanation - External magnets can concentrate magnetic nanoparticles at desired locations, enhancing local drug concentration.
Correct answer is: Applying an external static magnetic field to guide magnetic nanoparticles to the target site
Q.81 Which of the following polymers is known for its biodegradability and is FDA‑approved for drug delivery applications?
Polyethylene glycol (PEG)
Polylactic acid (PLA)
Polystyrene (PS)
Polyvinyl chloride (PVC)
Explanation - PLA degrades into lactic acid, is biocompatible, and widely used in FDA‑cleared devices.
Correct answer is: Polylactic acid (PLA)
Q.82 A nanocarrier that releases drug upon exposure to a specific enzyme overexpressed in tumor tissue is employing:
pH‑triggered release
Enzyme‑responsive release
Thermo‑responsive release
Magnetically‑responsive release
Explanation - Enzyme‑responsive carriers contain cleavable linkers recognized by tumor‑specific enzymes.
Correct answer is: Enzyme‑responsive release
Q.83 In drug delivery research, the term 'pharmacodynamics' refers to:
The study of drug absorption, distribution, metabolism, and excretion
The study of the biochemical and physiological effects of drugs and their mechanisms of action
The mechanical strength of tablets
The electrical conductivity of drug solutions
Explanation - Pharmacodynamics describes what the drug does to the body.
Correct answer is: The study of the biochemical and physiological effects of drugs and their mechanisms of action
Q.84 Which of the following is a key factor that determines whether a nanoparticle can passively accumulate in a tumor via the EPR effect?
Particle color
Particle size between 10‑200 nm
Particle magnetic moment
Particle electrical resistance
Explanation - Nanoparticles within this size range can extravasate through tumor vasculature and avoid rapid renal clearance.
Correct answer is: Particle size between 10‑200 nm
Q.85 Which of the following is a primary advantage of using 'polymer‑based nanofibers' for transdermal drug delivery?
They provide a magnetic field
They offer a large surface area for drug loading and controlled release
They emit visible light
They increase the drug's electrical charge
Explanation - Electrospun nanofibers have high surface‑to‑volume ratio, facilitating drug loading and sustained release through the skin.
Correct answer is: They offer a large surface area for drug loading and controlled release
Q.86 A drug delivery system that uses a 'proton pump inhibitor' to increase gastric pH before delivering a drug is an example of:
Passive targeting
pH‑modulating pre‑treatment to improve drug stability
Magnetic targeting
Electrical stimulation
Explanation - Altering gastric pH can protect acid‑labile drugs, enhancing their bioavailability.
Correct answer is: pH‑modulating pre‑treatment to improve drug stability
Q.87 Which of the following is an example of an 'external stimulus' used to trigger drug release?
Enzyme overexpression
pH change in tumor microenvironment
Application of an alternating magnetic field
High intracellular ATP levels
Explanation - External stimuli like magnetic fields can be applied on demand to activate drug release from responsive carriers.
Correct answer is: Application of an alternating magnetic field
Q.88 Which of the following best describes the purpose of a 'pharmacokinetic study' in the development of a novel drug delivery system?
To evaluate the mechanical strength of the carrier
To assess how the body absorbs, distributes, metabolizes, and excretes the drug
To measure the electrical conductivity of the formulation
To determine the magnetic susceptibility of the carrier
Explanation - Pharmacokinetic studies provide data on drug concentration over time, crucial for dosage and efficacy assessment.
Correct answer is: To assess how the body absorbs, distributes, metabolizes, and excretes the drug
Q.89 Which of the following nanocarrier types is inherently capable of providing contrast for magnetic resonance imaging (MRI)?
Gold nanoparticles
Superparamagnetic iron oxide nanoparticles (SPIONs)
Silica nanospheres
Polymeric micelles
Explanation - SPIONs act as T2 contrast agents in MRI, allowing simultaneous imaging and drug delivery.
Correct answer is: Superparamagnetic iron oxide nanoparticles (SPIONs)
Q.90 In a drug delivery context, 'hydrophilic' drugs are best encapsulated within:
The lipid bilayer of liposomes
The aqueous core of liposomes or hydrophilic polymeric networks
The hydrophobic core of polymeric micelles
Metallic cores
Explanation - Hydrophilic drugs dissolve in water, making the aqueous interior of liposomes or hydrogel matrices ideal for loading.
Correct answer is: The aqueous core of liposomes or hydrophilic polymeric networks
Q.91 Which of the following statements about 'active targeting' is true?
It relies solely on particle size for accumulation
It uses surface ligands to bind specific receptors on target cells
It only works for oral drug delivery
It eliminates the need for any carrier material
Explanation - Active targeting functionalizes carriers with molecules (e.g., antibodies, peptides) that recognize disease‑specific receptors.
Correct answer is: It uses surface ligands to bind specific receptors on target cells
Q.92 A nanocarrier that releases drug upon exposure to a specific wavelength of near‑infrared (NIR) light is using which type of trigger?
Photothermal
Magnetic
Electrical
pH
Explanation - NIR light can be absorbed by certain nanomaterials, converting light to heat and triggering drug release.
Correct answer is: Photothermal
Q.93 Which of the following is a potential drawback of using high‑dose systemic chemotherapy without targeted delivery?
Reduced drug efficacy
Increased off‑target toxicity and side effects
Improved drug solubility
Enhanced drug stability
Explanation - Non‑targeted chemotherapy distributes throughout the body, harming healthy tissues and causing severe side effects.
Correct answer is: Increased off‑target toxicity and side effects
Q.94 Which analytical technique is most suitable for determining the crystallinity of a drug within a polymeric matrix?
Differential scanning calorimetry (DSC)
Dynamic light scattering (DLS)
Zeta potential measurement
Fluorescence spectroscopy
Explanation - DSC measures heat flow associated with melting and glass transitions, indicating drug crystallinity within the carrier.
Correct answer is: Differential scanning calorimetry (DSC)
Q.95 In a 'nanopatch' designed for transdermal drug delivery, the primary mechanism of drug entry is:
Creating micro‑channels in the stratum corneum to bypass the barrier
Generating magnetic fields
Heating the skin
Applying electrical current
Explanation - Nanopatches contain microneedles or microstructures that physically breach the skin barrier, allowing drug diffusion.
Correct answer is: Creating micro‑channels in the stratum corneum to bypass the barrier
Q.96 Which of the following best defines 'biodegradability' in the context of polymeric drug carriers?
Ability to conduct electricity
Ability to break down into non‑toxic, biologically compatible by‑products
Ability to emit light
Ability to magnetically attract cells
Explanation - Biodegradable polymers degrade via hydrolysis or enzymatic action into safe metabolites.
Correct answer is: Ability to break down into non‑toxic, biologically compatible by‑products
Q.97 A nanocarrier that releases drug in response to an increase in temperature above 42 °C is an example of:
pH‑responsive
Thermo‑responsive
Magnetic‑responsive
Enzyme‑responsive
Explanation - Thermo‑responsive carriers change their physical state or permeability at defined temperature thresholds.
Correct answer is: Thermo‑responsive
Q.98 Which of the following is a major consideration when designing a nanocarrier for intravenous injection?
Ensuring particle size >5 µm to avoid capillary blockage
Maintaining sterility and avoiding aggregation in blood plasma
Making the carrier highly positively charged
Using a magnetic core
Explanation - Aggregated particles can cause embolism; sterility prevents infection and aggregation ensures safe circulation.
Correct answer is: Maintaining sterility and avoiding aggregation in blood plasma
Q.99 Which of the following statements about 'polymeric micelles' is correct?
They have a solid crystalline core
They are formed by self‑assembly of amphiphilic block copolymers above the CMC
They cannot encapsulate hydrophobic drugs
They are typically larger than 1 µm
Explanation - Amphiphilic block copolymers self‑assemble into core‑shell micelles once the concentration exceeds the critical micelle concentration.
Correct answer is: They are formed by self‑assembly of amphiphilic block copolymers above the CMC
Q.100 Which of the following is a common approach to increase the oral bioavailability of poorly water‑soluble drugs?
Encapsulation in lipid‑based nanocarriers such as solid lipid nanoparticles
Increasing particle size to >10 µm
Adding a magnetic core
Using a high‑pH tablet coating
Explanation - Lipid carriers improve solubility and lymphatic uptake, enhancing oral bioavailability of lipophilic drugs.
Correct answer is: Encapsulation in lipid‑based nanocarriers such as solid lipid nanoparticles
Q.101 A drug delivery system that utilizes 'layer‑by‑layer' assembly of polyelectrolytes to control release is an example of:
Nanoparticle aggregation
Multilayered coating strategy
Magnetic targeting
Ultrasound activation
Explanation - Layer‑by‑layer (LbL) deposition creates alternating charged layers, allowing precise control of drug diffusion rates.
Correct answer is: Multilayered coating strategy
Q.102 Which of the following is a typical characteristic of a 'nanoparticle' intended for pulmonary delivery?
Aerodynamic diameter between 1‑5 µm
Aerodynamic diameter >10 µm
Magnetic susceptibility above 1 T
Electrical conductivity above 1 S/m
Explanation - Particles in this range can reach the deep lung (alveolar region) without being exhaled or deposited in the upper airway.
Correct answer is: Aerodynamic diameter between 1‑5 µm
Q.103 The term 'therapeutic index' in drug development refers to:
The ratio of drug cost to efficacy
The ratio between toxic dose (TD₅₀) and effective dose (ED₅₀)
The electrical voltage needed for drug release
The magnetic field strength required for targeting
Explanation - A higher therapeutic index indicates a larger safety margin between effective and toxic doses.
Correct answer is: The ratio between toxic dose (TD₅₀) and effective dose (ED₅₀)
Q.104 Which of the following nanocarriers can be functionalized with aptamers for specific cell targeting?
Gold nanoparticles
Silica nanoparticles
Both gold and silica nanoparticles
None of the above
Explanation - Aptamers can be covalently attached to various nanomaterial surfaces, including gold and silica, for selective binding.
Correct answer is: Both gold and silica nanoparticles
Q.105 A drug delivery system that utilizes a 'pulsatile' release profile is designed to:
Deliver drug continuously at a constant rate
Release drug in discrete bursts at predetermined times
Release drug only when exposed to magnetic fields
Never release the drug
Explanation - Pulsatile systems mimic physiological rhythms or dosing schedules, releasing drug in timed pulses.
Correct answer is: Release drug in discrete bursts at predetermined times
Q.106 Which of the following is a common reason for incorporating a 'targeting ligand' onto the surface of a nanocarrier?
To increase particle density
To enhance specificity toward diseased cells expressing the corresponding receptor
To make the carrier magnetic
To lower the drug loading capacity
Explanation - Targeting ligands (e.g., antibodies, peptides) recognize overexpressed receptors on target cells, improving uptake.
Correct answer is: To enhance specificity toward diseased cells expressing the corresponding receptor
Q.107 In the context of drug delivery, what does the acronym 'DDS' stand for?
Dynamic Delivery System
Drug Delivery System
Digital Diagnostic Scanner
Direct Data Stream
Explanation - DDS refers to any formulation or device designed to transport a pharmaceutical compound to a target site.
Correct answer is: Drug Delivery System
Q.108 Which of the following is a benefit of using 'nanoparticles' for vaccine delivery?
They can directly alter DNA sequences
They can improve antigen stability and enhance immune response
They make the vaccine magnetic
They increase the vaccine’s electrical conductivity
Explanation - Nanoparticles protect antigens from degradation and can act as adjuvants, boosting immunogenicity.
Correct answer is: They can improve antigen stability and enhance immune response
Q.109 Which of the following is a characteristic feature of a 'hydrogel' used in drug delivery?
Rigid crystalline structure
High water content and swelling ability
Strong magnetic properties
Conductivity comparable to metals
Explanation - Hydrogels are cross‑linked polymer networks that can absorb large amounts of water, enabling controlled drug release.
Correct answer is: High water content and swelling ability
Q.110 Which of the following is a common method to attach targeting ligands to the surface of a nanoparticle?
Physical adsorption only
Covalent coupling via functional groups such as amine or carboxyl
Embedding the ligand in the core
Heating the nanoparticle to melt the ligand
Explanation - Covalent bonds provide stable attachment of ligands, ensuring they remain on the surface during circulation.
Correct answer is: Covalent coupling via functional groups such as amine or carboxyl
Q.111 In a drug delivery context, the term 'reticuloendothelial system' (RES) refers to:
The group of organs that filter blood and clear foreign particles, primarily liver and spleen
The nervous system responsible for pain perception
The system that regulates blood pressure
The magnetic field generating organ
Explanation - RES (also called mononuclear phagocyte system) removes opsonized particles from circulation, affecting nanoparticle half‑life.
Correct answer is: The group of organs that filter blood and clear foreign particles, primarily liver and spleen
Q.112 Which of the following best describes the role of 'surface modification' in nanocarrier design?
Changing the particle’s color
Improving stability, biocompatibility, and targeting ability
Increasing the particle’s magnetic field
Reducing the particle’s size below 1 nm
Explanation - Surface modification (e.g., PEGylation, ligand attachment) tailors interactions with biological environments.
Correct answer is: Improving stability, biocompatibility, and targeting ability
Q.113 Which of the following is a typical advantage of using 'polymeric nanoparticles' over 'liposomes' for drug delivery?
Higher magnetic susceptibility
Better mechanical stability and tunable degradation rates
Intrinsic fluorescence
Inherent electrical conductivity
Explanation - Polymeric nanoparticles are generally more robust and allow precise control over degradation through polymer chemistry.
Correct answer is: Better mechanical stability and tunable degradation rates
Q.114 A nanocarrier that releases drug when the surrounding temperature rises above the polymer's glass transition temperature (Tg) is classified as:
pH‑responsive
Thermo‑responsive
Magnetically‑responsive
Enzyme‑responsive
Explanation - Crossing Tg changes polymer chain mobility, facilitating drug diffusion.
Correct answer is: Thermo‑responsive
Q.115 Which of the following is a primary concern when delivering drugs across the blood‑brain barrier (BBB)?
High magnetic field strength
Low particle charge
Limited permeability due to tight endothelial junctions
Excessive particle fluorescence
Explanation - The BBB restricts entry of most molecules; nanocarriers must be engineered to overcome this barrier.
Correct answer is: Limited permeability due to tight endothelial junctions
Q.116 Which of the following best defines 'nanotoxicology'?
Study of nanomaterials used in electronics
Study of adverse effects of nanomaterials on living organisms and the environment
Study of magnetic fields generated by nanoparticles
Study of the electrical conductivity of nanomaterials
Explanation - Nanotoxicology assesses potential health and ecological risks associated with nanomaterials.
Correct answer is: Study of adverse effects of nanomaterials on living organisms and the environment
Q.117 In the context of drug delivery, what does the acronym 'EPR' stand for?
Electron Paramagnetic Resonance
Enhanced Permeability and Retention
External Pressure Regulation
Electrochemical Potential Ratio
Explanation - EPR is a phenomenon that allows nanosized particles to accumulate in tumor tissue due to leaky vasculature.
Correct answer is: Enhanced Permeability and Retention