Pharmaceutics Exam III
What is the calculation to find AUC?
((C1+C2)/2) * (T2-T1)
Most pharmaceutical suspensions have a particle size range of: a. 1-500 nm b 500-1000 nm c. 1-50 micrometers d. 50-1000 micrometers
C
Which molecule is a natural emulsifying agent? a. span b. tween c. acacia d. lactose
C
In a ______, one phase is fragmented into small pieces which are distributed in a continuous phase.
Dispersion
(dissolution:absorption) is dependent on product formulation and the manufacturing process.
Dissolution
The _____ test is the standard method published by the USP to determine whether tablets or capsules disintegrate within the prescribed time when placed in a liquid medium.
Dissolution
______ is the process of releasing the drug out of the solid formulations into solution within the GI tract.
Dissolution
The _____ test is an in vitro method to demonstrate how efficiently a drug is released from a solid dosage form.
Dissolution Test
True or False. Suspensions can be used for soluble and insoluble drugs.
False
True or False. The Dissolution Test provides information on drug absorption across the GI tract.
False
True or False. The dissolution process is generally dependent on the physical/chemical properties of the drug and the physiology condition.
False
True or False. The media volume of the dissolution test is specified in a monograph, otherwise 1000 mL in the USP/NF.
False
True or False. The primary goal of surfactants is to increase surface tension.
False
True or False. The same Cmax guarantees the same therapeutic effect.
False
True or False. Two formulations that satisfy the criteria of the pharmaceutical equivalence always satisfy the criteria of bioequivalence.
False
True or False. USP apparatus II is generally preferred for capsules and for dosage forms that tend to float or distintegrate slowly.
False
The smaller the drug particle size, the (slower:faster) the dissolution rate.
Faster
_____ are a type of emulsifying agent that are adsorbed at the interface between two immiscible liquid phases.
Finely divided solid particles
What is the most effective method to reduce particles below 10 micrometers?
Fluid Energy Grinding
_____ uses shearing action of high velocity streams of compressed air to reduce particle size.
Fluid Energy Grinding
A _____ is a dispersion that consists of gas bubbles in liquid.
Foam
_____ dosage forms include tablets, capsules, grandules, powders, gels, solutions, syrups, suspensions and emulsions.
Oral
_____ described the evolution of an inhomogenous structure over time.
Ostwald Ripening
_____ dosage forms include injections, implants and irrigation.
Parenteral
_____ is defined as the contracting and relaxing of muscles that line your esophagus, stomach, small intestine, and colon in a rhythm that produces a wavelike motion.
Peristalsis
A _____ is a dispersion that consists of solid particles in gas.
Smoke
(Suspensions:Solutions) are employed to a higher extent.
Solutions
What is the best material for an aerosol container?
Stainless Steel
_____ are a type of emulsifying agent that are adsorbed at oil-water interfaces to form monomolecular films and reduce interfacial tension.
Surfactants
_____ are molecules that adsorbe to interfaces to reduce interfacial tension.
Surfactants
_____ are liquid preparations that consist of solid particles dispersed throughout a liquid phase in which the particles are not soluble.
Suspensions
_____ is the intravenous administration of calories, nitrogen and other nutrients to achieve tissue synthesis and anabolism.
TPN
True or False. Mixture of low HLB and high HLB surfactants gives better coverage at the interface.
True
True or False. Most pharmaceutical suspensions have a particle size range of 1-50 micrometers.
True
True or False. SDS and soap are examples of anionic surfactants.
True
True or False. Surfactants tend to be located at the interface between a polar and a nonpolar phase.
True
True or False. Suspensions can be used for insoluble drugs.
True
True or False. Suspensions have better bioavailability compared to capsules.
True
True or False. Tear turnover dilutes the drug.
True
True or False. The Dissolution Test assists in the determination of bioequivalence.
True
True or False. The standard bioequivalence study can be conducted using a two-treatment crossover study design including approximately 24-36 adults.
True
True or False. if excessive amounts of binder are applied, disintegration of the tablet will be retarded when the tablet is taken.
True
An ______ is the fitting attached to an aerosol valve stem, which when depressed or moved, opens the valve and directs the spray containing the drug preparation to the desired area.
actuator
What are the three methods of controlled flocculation?
add electrolytes add surfactants add hydrophilic polymers
The (conjunctival sac:corneal membrane) is a more effective barrier for drug absorption.
corneal membrane
Amorphous and Polymorphic forms are (crystal:salt) forms.
crystal
Ocular administration is normally into the _____
cul-de-sac
Increasing the viscosity of the dispersion medium (increases:decreases) the sedimentaiton rate.
decreases
Reducing particle size (increases:decreases) the sedimentaiton rate.
decreases
What are the three factors contributing to an efficient inhalation therapy?
drug device formulation
Which inhaler is a good choice for macromolecules?
dry powder
A _____ is a device that delivers drugs to the lungs in the form of a dry powder.
dry powder inhaler
What is the most important factor that determines the type of an emulsion?
emulsifying agent
The _____ is responsible for pumping excess fluid out of the stroma.
endothelium
The _____ blocks passage of foreign material, absorbs oxygen and cell nutrients from tears.
epithelium
What are the three basic layers of the cornea?
epithelium stroma endothelium
What are the three layers of ocular cells?
epithelium stromal endothelium
The (internal:external) phase is the continous phase in an emulsion.
external
Approximately, 90% of all the ocular formulations are applied as _____.
eye drops
True or False. A high HLB value indicates a molecule with more hydrophilic groups.
false
True or False. Anionic surfactants are commonly used for oral and parenteral emulsions.
false
The Amorphous crystal form has (fast:slow) dissolution.
fast
The delivery of drugs from hydrophilic matrices is (slow:fast) because the tear fluid rapidly penetrates into the matrix.
fast
What is the equation to calculate RHLB of an oil mixture?
foil1 * RHLBoil1 + foil1 * RHLBoil2 etc...
A (generic:brand) name drug requires a bioequivalence study.
generic
A ______ is the same as a brand name drug in dosage, safety, strength, how it is taken, quality, performance and intended use.
generic drug
What are the three possible components of the container?
glass metal plastic
Opthalmic ointments generally produce (greater:lesser) bioavailability than the equivalent aqueous solution.
greater
Rigid, hydrophobic contact lenses are (hard:soft)
hard
The (higher:lower) the HLB, the more hydrophilic it is.
higher
(hydrophobic:hydrophilic) excipients increase dissolution.
hydrophilic
The stroma is (lipophilic:hydrophilic)
hydrophilic
(hydrophobic:hydrophilic) excipients decrease dissolution.
hydrophobic
A (hypotonic:hypertonic) solution produces shrinking of tissues with a generally less severe effect.
hypertonic
A (hypotonic:hypertonic) solution produces painful swelling of tissues as water passes from the administration site into the tissues.
hypotonic
Coalescence is (reversible:irreversible)
iireversible
Emulsions have two phases that are (miscible:immiscible)
immiscible
Disintegrants (increase:decrease) dissolution.
increase
Glaucoma is an (increase:decrease) in intraocular pressure.
increase
Increasing the viscosity will (increase:decrease) the bioavailability of drugs.
increase
Suspending Agents (increase:decrease) the viscosity of suspensions.
increase
Precorneal retention and duration of action can be (increased:decreased) by using water-soluble matrices in which the drug is either dispersed or dissolved.
increased
The difference between pH of pilocarpine solutions causes (increased:decreased) lacrimation and loss of drug.
increased
What is the primary advantage of an ophthalmic ointment over an ophthalmic solution?
increased ocular contact time of the drug
Decreasing the uniformity of the dispersed particles (increases:decreases) the sedimentaiton rate.
increases
What are the four main uses of pharmaceutical aerosols?
inhalation topical vaginal rectal
Reducing particle size is an effective method to increase the dissolution rate of (soluble:insoluble) drug.
insoluble
Breaking is (reversible:irreversible)
irreversible
What is a common buffer used in ophthalmic preperations?
isotonic phosphate
The _____ and _____ of drug absorption are statistically measured.
rate; extent
The type of an emulsion formed is primarily determined by the _____ and the _____ used.
relative phase volumes emulsifying agent
Creaming is (reversible:irreversible)
reversible
Which category of contact lenses are best for drug delivery?
rigid, hydrophilic
What are the four categories of contact lenses?
rigid, hydrophobic rigid, hydrophilic flexible, hydrophobic flexible, hydrophilic
What is the most important step in the preparation of a stable emulsion?
selection of a proper emulsifying agent
_____ solutions are used to store, hydrate and disinfect hard lenses.
soaking
What are the two most widely used methods to adjust isotonicity of ophthalmic solutions?
sodium chloride equivalent method isotonic buffer
Flexible, hydrophilic contact lenses are (hard:soft)
soft
HLB is an indicator of the _____ of a surfactant.
solubility
What is the order of bioavailability between capsules, tablets, solutions and supensions?
solution > suspension > capsule > tablet
Ophthalmic _____ are sterile products athat are compounded and packaged for instillation into the eye.
solutions
What are the three conventional ocular drug delivery systems?
solutions suspensions ointments
What are the main two mechanisms of loss of ocular drug?
spillage removal by the naso-lacrimal apparatus
What are the main 4 types of sterilization during the process of ophthalmic preparation?
steam under pressure filtration gas sterilization radiation
What is the preferred method of sterilizaton?
sterile membrane filtration
What is the main difference between ophthalmic and dermatological ointments?
sterility
What is the most important requirement for ophthalmic preparations?
sterility and preservation
The _____ is comprised of water and collagen fibers and funcitons in nutrient transport.
stroma
What are the four classes of flocculating agents?
surfactant hydrophilic polymer clay electrolyte
A _____ is a dispersion that consists of solid particles in liquid.
suspension
_____ is irregular shaping of the cornea causing skewed vision.
Astigmatism
_____ is the separation of internal phase from emulsion.
Breaking
True or False. Suspension is a thermodynamically stable system.
False
Excessive binder leads to (slow:fast) dissolution.
Slow
Most good pharmaceutical suspensions have a particle size range of _____ micrometers.
1-50
Autoclaving is done at _____ degrees C for _____ minutes.
121; 15
The (1st:2nd:3rd) stage of the dissolution acceptance test is when each of the 6 units is not less than Q + 5.
1st
What is the full patent life of a brand drug?
20 years
Viscosity desired in an ophthalmic solution is between _____ and _____ cps.
25;50
The (1st:2nd:3rd) stage of the dissolution acceptance test is when the average of 12 units is equal to or greater than Q and no unit is less than Q-15%.
2nd
What is the maximum volume of cul-de-sac?
30 microliters
What is the volume of drug that can be tolerated without spillage?
30 microliters
The (1st:2nd:3rd) stage of the dissolution acceptance test is when the average of 24 units is equal to or greater than Q and no more than 2 units are less than Q-15% and no unit is less than Q-25%.
3rd
For maximum comfort, ophthalmic preperations should be at pH _____.
7.4
Which of the following processes are reversible? a. flocculation b. aggregation c. caking
A
What are the six components of a suspension formulation?
API wetting agent flocculating agent suspending agent dispersion medium other ingredients
_____ represents the total amount of drug absorbed into the blood circulation.
AUC
_____ is the ratio of the AUC for the oral dosage form to the AUC obtained by IV administration.
Absolute Bioavailability
(dissolution:absorption) is dependent on the physical and chemical properties of the drug and the physiology condition.
Absorption
_____ is the process of transporting the drug from the GI tract into the systemic circulation.
Absorption
_____ refers to the fine mist of spray tat results from a pressurized system.
Aerosol
_____ are products that are packaged under pressure and contain therapeutically active ingredients that are released upon activation of an appropriate valve system.
Aerosols
Surfactants are _____ molecules, meaning they have polar and nonpolar groups.
Amphiphilic
The _____ is the part of ocular anatomy that maintains pressure and bathes nutrients.
Aqueous Humor
What does AUC stand for?
Area Under the Curve
______ is the rate and extent to which the active ingredient or active moiety is absorbed from a drug product and becomes available at the site of action.
Bioavailability
_____ is the compaction of aggregates that settle at the bottom.
Caking
______ is when ophthalmic preparations are free from foreign particles, normally by filtration.
Clarity
_____ are commonly employed as the flocculating agent for oral suspensions
Clays
(Clinical:Therapeutic) equivalence occurs when the same drug from two or more dosage forms gives identical effects as measured by a pharmacological response or by control of a symptom or disease.
Clinical
A _____ is a dispersion that consists of liquid droplets in gas.
Cloud
____ is the peak concentration.
Cmax
_____ is when droplets merge with each other to form large drops.
Coalescence
(Molecular:Colloidal:Coarse) Dispersion are descriptive of most emulsions and suspensions.
Coarse
(Molecular:Colloidal:Coarse) Dispersion are visible under optical microscope, don't pass through filter paper or semipermeable membranes and don't diffuse.
Coarse
(Molecular:Colloidal:Coarse) Dispersion has particle sizes greater than 0.5 micrometers.
Coarse
_____ were designed to be a disposable, short-term therapeutic bandage lens for cornea.
Collagen shields
(Molecular:Colloidal:Coarse) Dispersion are visible under electron microscope, pass through filter paper, don't pass through a semipermeable membrane and diffuse very slowly.
Colloidal
(Molecular:Colloidal:Coarse) Dispersion has particle sizes between 1 and 500 nm.
Colloidal
_____ and _____ mucosae play a role in systemic absorption of ocularly applied drugs.
Conjunctival; Nasal
_____ is the migration of droplets to the surface or the bottom of emulsions.
Creaming
Emulsions can be used: a. to increase drug solubility b. to increase drug stability c. for parenteral dosage form d. all of the above
D
How do you overcome the problems of unstable suspensions? a. reduce interfacial area b. reduce interfacial tension c. control flocculation d. all of the above
D
Ingredients that may be used as suspending agents include: a. methylcellulose b. acacia c. Talc d. a and b e. all of the above
D
Mechanisms that are thought to provide stable emulsifications include the: a. formation of interfacial film b. lowering of interfacial tension c. presence of charge on dispersed droplets d. all of the above
D
The particles in an ideal suspension should satisfy which of the following criteria? a. their size should be uniform b. they should be stationary or move randomly c. they should remain discrete d. all of the above
D
The sedimentation of particles in a suspension can be minimized by: a. adding sodium benzoate b. increasing the viscosity of the suspension c. reducing the particle size of the active ingredient d. b and c e. all of the above
D
What is a physicochemical property that affects bioavailability? a. molecular weight b. solubility c. manufacturing variables d. all of the above
D
Which avoids the agglomeration of suspended particles? a. add + or - charges on the surface of suspended particles (high zeta potential) b. absorption of small colloids on surface of suspended particles c. create steric hindrance on surface of suspended particles d. all of the above
D
Which of the following parameters are needed to evaluate bioequivalence? a. Cmax b. Tmax c. AUC d. all of the above e. b and c
D
Which part of the lung is the absorption site for inhaled drugs? a. trachea b. main bronchi c. small bronchi d. alveoli
D
_____ are "tree-like" polymers with extensive branching around a central core.
Dendrimers
_____ can be used for delivery of a variety of molecules including genes.
Dendrimers
A ______ is the density difference between suspended particles and the medium.
Determining Factor
Pharmaceutical suspensions can be used for _____ administration. a. oral b. parenteral c. topical d. rectal e. all of the above
E
What are factors relating to formulation? a. binder b. disintegrant c. lubricant d. hydrophobic/hydrophilic excipients e. all of the above
E
Which of the following is a factor affecting drug dissolution? a. factors related to formulation types b. factors related to manufacture process c. factors related to API d. dissolution conditions e. all of the above
E
_____ dosage forms include solutions, suspensions, ointments and creams.
Ear
_____ are molecules that lower interfacial tension and form a film at the interface.
Emulsifying Agents
An _____ is a dispersion that consists of liquid droplets in another liquid.
Emulsion
_____ are two-phase systems in which one liquid is dispersed throughout another liquid in the form of small droplets.
Emulsions
_____ dosage forms include solutions, ointments and creams.
Eye
True or False. A generic drug must have the same conditions of use as a brand drug.
False
True or False. Continuous valve is mainly used for inhalation products.
False
True or False. Filtration is more reliable than the autoclave.
False
True or False. Increasing the viscosity of dispersion medium is the best strategy to improve the physical stability of a suspension.
False
True or False. Most of the inhalation dose reaches the alveoli.
False
True or False. Pharmaceutical Equivalence is the same thing as Bioequivalence.
False
Opthalmic preparations require special consideration with regard to... a. sterility b. preservation c. clarity d. isotonicity e. buffering f. viscosity g. all of the above
G
What is a physilogical factor that affects bioavailability? a. pH of GI b. GI Motility c. metabolism during absorption process d. age/sex e. disease status f. transporters/efflux systems g. all of the above
G
_____ can be employed for heat sensitive materials.
Gas Sterilization
In 1851, _____ derived an expression for the settling velocity of suspended particles.
George Stokes
Is HFA or CFC better?
HFA
In 1984, what created the generic drug industry?
Hatch-Waxman Act
_____ are a type of emulsifying agent that form multimolecular films around the dispersed droplets of oil in an O/W emulsion.
Hydrophilic Colloids
The ______ is an arbitrary scale of values used as a measure of the hydrophilic-lipophilic balances of surfactants.
Hydrophilic-Lipophilic Balance (HLB)
(Myopia:Hyperopia) is farsightedness.
Hyperopia
The USP Apparatus (I:II) is generally preferred for capsules and for dosage forms that tend to float or disintegrate slowly.
I
The USP Apparatus (I:II) is generally the first choice for immediate release dosage forms.
II
Ophthalmic suspensions provide a (slower:faster) release of the drug from the vehicle.
Slower
Reducing particle size (increases:decreases) surface area.
Increases
The (internal:external) phase is the dispersed phase in an emulsion.
Internal
_____ involves increased transport of ionic drugs by application of an external electric current.
Iontophoresis
(Myopia:Hyperopia) is nearsightedness.
Myopia
______ dosage forms include solutions and inhalations.
Nasal
_____ surfactants are commonly used for oral and parenteral formulations because of their low irritation/toxicity.
Nonionic
_____ surfactants are commonly used in cleaning solutions.
Nonionic
What equation is used when looking at factors related to API?
Noyes-Whitney
(O/W:W/O) is more susceptible to microorganisms.
O/W
Most pharmaceutical emulsions are (O/W:W/O)
O/W
The _____ system was the first controlled topical dosage form marketed for use in the eye.
Ocusert
(Smaller:Larger) particles have higher solubility.
Smaller
_____ eye drops are used as a topical miotic to reduce the intraocular pressure associated with glaucoma.
Pilocarpine
90-95% of the drug is lost by _____ loss such as tear turnover, drainage, systemic absorption and in situ metabolism.
Precorneal
_____ is used to maintain sterility during use.
Preservation
All ophthalmic preservative agents are innefective against some strains of ______.
Pseudomonas aeruginosa
_____ is the amount of dissolved active ingredient expressed as a percentage of the labeled dose.
Q
_____ dosage forms include suppositories, ointments, creams, powders and solutions.
Rectal
_____ dosage forms include aerosols, inhalations, sprays and gases.
Respiratory
(Salt:Crystal) forms have higher solubility.
Salt
(Clinical:Therapeutic) equivalence implies that one structurally different chemical can yield the same clinical result as another chemical.
Therapeutic
_____ is the time of the peak concentration.
Tmax
_____ dosage forms include ointments, creams, pastes, lotions, gels, solutions, topical aerosols and transdermal patches.
Topical
_____instillation is used to treat local diseases affecting the eye.
Topical
According to the FDA, a generic drug product is considered bioequivalent if the rate and extent of absorption do not show a significant difference from that of the pioneer drug product when administered at the same molar dose of the therapeutic ingredient under the same experimental conditions.
True
True or False. A suspension is a type of dispersion.
True
True or False. Bioavailability is defined as the rate and extent to which the active ingredient or active moiety is absorbed from a drug product and becomes available at the site of action.
True
True or False. Coating may affect the dissolution.
True
True or False. Detergents, soaps, emulsifies, defoamers, dispersants and wetting agents are examples of surfactants.
True
True or False. Dissolution test does not provide any information on drug absorption across the GI tract.
True
True or False. Drug products are considered bioequivalent, if they are pharmaceutical equivalents whose rate and extent of absorption are not statistically different when administered at the same molar dose under similar conditions.
True
True or False. Each lipophilic phase used in O/W emulsions has a required HLB.
True
True or False. Equivalent doses of the same drug, when fully absorbed, produce the same AUC.
True
True or False. HFA has no impact on the ozone layer.
True
True or False. In in vivo bioequivalence test, AUC of the generic drug to the brand name drug is within 80-125% in both the fasting and fed states.
True
True or False. Milk is an Emulsion
True
_____ is not the drug administered, but the drug available to exert its effect.
True Dose
_____ dosage forms include suppositories, ointments, creams, solutions, sprays, tablet, capsules and foam.
Vaginal
_____ enhancers enable the formulation to remain in the eye longer and gives more time for the drug to exert its therapeutic activity or undergo absorption.
Viscosity
______ function by displacing the air in the crevices of the particles, dispensing the particles, and allowing penetration of dispersion medium into the powder.
Wetting Agents
What does ANDA stand for?
abbreviated new drug application
What are the three primary examples of natural emulsifying agents?
acacia lecithin pectin
A(n) (acidic:basic) pH is needed to increase the stability of pilocarpine.
acidic
What are the three possible components of metal containers?
aluminum stainless steel tin-plated steel
What is the most commonly used surfactant type?
anionic
What are the four types of surfactants?
anionic nonionic cationic amphoteric
Drug products are considered _____ if they are pharmaceutical equivalents whose rate and extent of absorption are not statistically different when administered at the same molar dose under similar conditions.
bioequivalent
What is the primary didadvantage of an ophthalmic ointment?
blurred vision
A (generic:brand) name drug requires animal and clinical studies.
brand
_____ solutions are used to remove surface contaminants .
cleaning
Creaming increases the likelihood of _____.
coalescence
What are the two types of propellant?
compressed gases liquefied gases
The absorption of drug takes place through either the _____ or _____.
conjunctival sac corneal membrane
What are the five components of aerosol systems?
container propellant API valve actuator
In a (continuous:metered) valve, the medication is released as long as the actuator is pressed.
continuous
What are the two types of valves?
continuous valve metered valve
Drugs administered by instillation must penetrate the eye primarily through _____.
cornea
Ocular drugs have to be delivered to the _____ area.
cornea
The _____ provides a mechanical and chemical barrier for foreign substances.
cornea
The main route of ocular absorption is across the _____
cornea
A _____ is when compressed gas passes through a narrow orifice creating an area of low pressure at the outlet of the adjacent liquid feed tube, resulting in drug solution being drawn up from the fluid reservoir and shattered into small droplets in the gas stream.
jet nebulizer
The _____ gland produces water which bathes the eye.
lacrimal
The dissolution rate of large particles in ocular suspensions is (larger:smaller) than that of small particles.
larger
What are the two sources of radiation for sterilization by radiation?
linear electron accelerators radioisotopes
The endothelium is (lipophilic:hydrophilic)
lipophilic
The epithelium is (lipophilic:hydrophilic)
lipophilic
Ocular bioavailability of Pilocarpine is (high:low).
low
Ocular bioavailability of topical drugs is (high:low).
low
The bioavailability of aqueous ophthalmic solutions is usually (low:high).
low
In a (continuous:metered) valve, a uniform quantity of medication is released when the actuator is pressed.
metered
What is most widely used aerosol delivery device?
metered dose inhaler
A _____ is a pressurized device that uses propellant to deliver a metered dose through the mouth piece upon the actuation of the valve.
metered-dose inhaler
Ophthalmic suspensions are prepared by _____ techniques to minimize potential irritation.
micronization
(Molecular:Colloidal:Coarse) Dispersion are invisible in electron microscopes, pass through semipermeable membranes and have rapid diffusion.
molecular
(Molecular:Colloidal:Coarse) Dispersion has particle sizes less than 1 nm.
molecular
What are the three classifications of dispersed systems?
molecular dispersion colloidal dispersion coarse dispersion
The emulsion after homogenisation has a (wider:narrower) range of size averaging around (8:1) micrometers.
narrower; 1
A _____ is a device to administer medication to the lungs of patient in the form of a mist.
nebulizer
What does NDA stand for?
new drug application
HLB is only calculated for _____ surfactants.
nonionic
What are the three types of synthetic emulsifying agents?
nonionic anionic cationic
In a(n) _____ emulsion, oil is the dispersed phase and water is the continuous phase.
oil-in-water
The _____ region and the _____ are filters to remove particles from the inhaled air.
orpharyngeal; bronchial tree
What is the most important single consideration in the physical instability of a suspension?
particle size
When reducing sedimentation rate, it is preferred to adjust the dispersed (particles:medium).
particles
The _____ supplies the necessary pressure within an aerosol system to expel material from the container and, in combination with other components, to convert the material into the desired physical form.
propellant
Which is the most expensive sterilization process?
radiation
True or False. A blend of two or more surfactants is better for the stability of emulsions.
true
A _____ uses piezoelectic crystal vibrating at high frequency to generate a foundaiton of liquid in the nebulizer chamber, the higher the frequency, the smaller the droplet size
ultrasonic nebulizer
Which of the following systems may degrade macromolecules during the generation of aerosols? a. metered-dose inhaler b. jet nebulizer c. ultrasonic nebulizer d. dry powder inhaler
ultrasonic nebulizer
The primary function of the _____ is to regulate the flow of the therapeutic agent and propellant from the container.
valve
Most ocular injections occur in the _____.
vitreous body
In a(n) _____ emulsion, water is the dispersed phase and oil is the continous phase.
water-in-oil
The corneal epithelium is considered a tight epithelium due to the presence of tight junctions called _____
zonula occludens