Drug Delivery I Exam I Fall 2025

This flashcards set covers key concepts from the Drug Delivery I Exam I Fall 2025 lecture notes, focusing on definitions and explanations relevant to drug delivery systems, properties of solutions, electrolytes, and absorption processes.

Ionization constants

Used to measure the strength of acids and bases.

Electrolytes

Substances that conduct an electrical current when dissolved in water.

Hydrolysis

The interaction of the ions of salts with the ions of water.

Heat of Solution

The overall energy exchanged when solute and solvent are combined.

Noyes-Whitney relationship

Describes the relationship between the rate of dissolution and various factors affecting solute dissolution.

Clearance in alkaline urine

Weak acids with a pKa in the range of pH 3.0 to 7.5 are excreted with high clearance.

Passive diffusion

The most common method for drug permeation across the lipid bilayer of biological membranes.

Dissolution profile

A test necessary for predicting in vitro absorption from solid dosage forms.

Solubility

The concentration of a solute when the solvent has dissolved all that it can at a given temperature.

Colligative properties

Properties that depend only on the number of solute particles in a solution.

Ideal Solution

A solution with no change in physical properties other than dilution when mixed.

Homogeneous mixture

A solution that is chemically and physically uniform throughout.

Chemical stability

Stability that can result from various chemical reactions affecting a molecule.

Surface tension

A physical property of liquids that decreases with an increase in temperature.

Boiling Point

The temperature at which the vapor pressure of a liquid equals atmospheric pressure.

Absorption site for IV infusion

None, formulated to give a systemic effect.

Bioavailability

The fraction of an administered dose of unchanged drug that reaches systemic circulation.

Pharmaceutical solutions

Solutions mostly composed of solids dissolved in water or other liquids.

Epidural injection

A method of administering medication that bypasses the gastrointestinal tract.

Weakly acidic drugs

Drugs that tend to dissolve better in the stomach where they are ionized.

Sublingual route

The site of administration under the tongue.

Liquid state

A state of matter that occupies a definite volume and takes the shape of its container.

The strength of acids and bases

Depending on the pH of the environment in which organic weak electrolytes are present, they can exist in either an ionized form or an unionized form. This degree of ionization can affect the absorption, transport, and excretion of drugs. What are ionization constants used to measure?

Electrolytes can conduct an electrical current

In an aqueous solution, electrolytes exhibit important properties that differentiate them from nonelectrolyets. Which of the following is a property?

> B: Electrolytes can conduct an electrical current

n an aqueous solution, electrolytes exhibit important properties that differentiate them from nonelectrolytes. Which of the following is a property?

X A: Electrolytes tend to show slow chemical reactions compared with nonelectrolyte solutions

B: Electrolytes can conduct an electrical current
X C: Electrolytes do not exhibit anomalous colligative properties compared with nonelectrolytes
X D: Electrolytes can be classified into four groups, depending on their ability to ionize in an aqueous solution.

The interaction of the ions of a salt with water is known as hydrolysis, which can lead to the solution being neutral, acidic, or basic depending on the salt's properties.

A salt is formed by an acid-base reaction involving either a proton donation or a proton acceptance. When a salt 5/5

is added to water, the solution can be neutral, acidic, or basic, depending on the salt. Which of the following terms is the interaction of the ions of the salts with the ions of water?

> A: Hydrolysis
X B: Anhydrous
X C: Cation Exchange X D: Anion Exchange

Heat of solution

When the solute and the solvent are combined, energy is released. The net exchange of energy can be positive or negative. The overall energy exchanged is called the ______________________ .

> A: Heat of Solution
X B: Heat of Vaporization X C: Heat of Combustion X D: Heat of Dissolution

Noyes Whitney

Dissolution is well modeled by the __________________ relationship, which describes the relationship between the rate of dissolution and such properties as solute particle surface area (a function of particle size), the thickness of a stagnant solvent layer surrounding the drug particle, the concentration gradient between that in the stagnant layer and that in the bulk solvent, and the solvent viscosity.

A: Noyes -Whitney X B: Danckwerts
X C: Fick’s Law
X D: Interfacial barrier

high

Weak acids with a pKa in the range of pH 3.0 to 7.5, which have ionization change with a change in urine pH, are 5/5

excreted at a _____________ clearance in highly alkaline urine.

X A: Low
> B: High
X C: Zero-order X D: Creatinine

Solubility & Partition Coefficient

Drug permeation across the lipid bilayer of biological membranes occurs most often by passive diffusion. Which 5/5

of the following is an important factor that will influence a drug's permeation through the bilayer? Select all that

apply.

> A: Solubility
> B: Partition Coefficient X C: Drug Concentration X D: Ion Charge

> B. To ensure batch to batch reproducibility
> C: Useful in quaility control parameters
> D: To help predict in vivo absorption of drugs from solid dosage forms

According to the United States Pharmacopeia, a dissolution study is an extremely important quality control test for solid dosage forms. Why is it necessary to study the dissolution profile of solid dosage forms? Select all that apply.

X A: To help predict in vitro absorption of drugs from solid dosage form > B:To ensure batch to batch reproducibility
> C: Useful in quaility control parameters
> D: To help predict in vivo absorption of drugs from solid dosage forms

increased pH

Add alcohol

Salts of weak acids and weak bases are completely ionized in water and are very soluble. What are two ways to

increase the solubility of a weak acid drug in aqueous solution?

Increase pH
> B: Add Alcohol
X C: Add Water
X D: Decreased pH

solubility

Which of the following can be defined as the concentration of a solute when the solvent has dissolved all the

solute that it can at a given temperature?

X A: Molarity
> B: Solubility
X C: Absorption
X D: Bioavailability

hypertonic fluids

Extravasation is the unintended leakage of fluid into the tissues surrounding a vein that occurs during the administration of certain fluids. The process can lead to necrosis (cell death) of the affected tissues. Which of the following fluids can cause extravasation and necrosis?

> A: Hypertonic Fluids X B: Hypotonic
X C: Isotonic
X D: Extratonic

Freezing point depression

Colligative properties only depend on the number of solute particles ions or molecules dissolved in the solution. Which of the following is a colligative property?

> A: Freezing Point Depression X B: Vapor Pressure Elevation
X C: Osmotic Pressure Elevation X D: Boiling Point Depression

Ideal Solution

Aqueous solution systems can be classified by thermodynamics. Which of the following can be described as a 5/5

solution for which there is no change in the physical properties of the components other than dilution when they

are mixed. No heat is given off or taken in, and the volume does not shrink or expand.

X A: Israel Solution > B: Ideal Solution X C: Real Solution X D: Raoult Solution

> A: Good for children and elderly patients
> B: Can be given by any route of administration

Which of the following is an advantage of formulating a solution as a drug delivery system? Select ALL that apply.

> A: Good for children and elderly patients
> B: Can be given by any route of administration X C: More pronounced taste
X D: It is a bulky formulation

Cyclization, Hydrolysis, oxidation

There are two types of stability that need to be considered for stability in the solid state: chemical and physical. 5/5

Chemical stability can result from a number of different chemical reactions depending on the molecule, conditions, and other components of the dosage form. Which of the following reactions is an example of this phenomenon? Select ALL that apply.

> A: Cyclization > B: Hydrolysis > C: Oxidation
X D: Combustion

linear

Surface tension is another physical property of liquids. The surface tension of liquids decreases with an increase in temperature. Therefore, the relationship between surface tension of liquids and temperature is nearly _____________ .

> A: Linear
X B: Peripheral
X C: Non-linear
X D: Perpendicular

Boiling point

The temperature at which the vapor pressure of a liquid equals the atmospheric pressure describes which of the following? Hint: Vapor pressure and this variable are inversely related.

> A: Boiling Point
X B: Freezing Point X C: Buffer Capacity X D: H- bonding

liquids occupies a definite volume and takes the shape of the container required to hold it.

Liquids are less compressible than gases and more compressible than solids

Which of the following statements is true about the liquid state of matter? Select ALL that apply. 5/5

> A: A liquid occupies a definite volume and takes the shape of the container required to hold it. > B: Liquids are less compressible than gases and more compressible than solids
X C: Liquids flow very readily, and the flow is not influenced by friction
X D: Liquids do not exhibit surface tension

Oxygen

Carbon Dioxide

One of the applications of gases in pharmaceutical sciences is in the interpretation of blood gases in patients. Which of the following is an important blood gases ? Select ALL that apply.

> A: Oxygen
> B: Carbon Dioxide X C: Hydrogen
X D: Sodium Chloride

temp

Along with potential energy, molecules of gases, liquids, and solids have kinetic or thermal energy. Kinetic energy is proportional to which of the following variables?

> A: Temperature X B: Pressure
X C: Volume
X D: Mass

London Forces

The two types of attractive forces are called cohesive forces and adhesive forces. Which of the following terms 5/5

describes the forces that originate from molecular internal vibrations in nonpolar molecules to produce attraction

that arises because of synchronized fluctuating dipoles in neighboring atoms?

> A: London Forces
X B: Debye Forces
X C: Dipole - Dipole Forces X D: Keesom Forces

most drugs are weak acids or bases

Some solubility in lipids and water is essential

Which of the following statements are true pertaining to factors that affect the fate of the drug in the body? Select ALL that apply.

> A: Most drugs are weak acids or bases
> B: Some solubility in lipids and water is essential
X C: Protein binding is an irreversible process
X D: Only bound drug can transfer from the blood to interstitial fluid

None, formulated to give a systemic effect

Which of the following is the primary absorption site and purpose of a drug given as an IV infusion ?

> A: None, formulated to give a systemic effect X B: None, for local action in the CNS
X C: Dura mater, local effect
X D: Stratum Corneum, systemic effect

Stratum Corneum

Which of the following is the primary absorption site of a drug given as a topical formulation ? 5/5

> A: Stratum Corneum
X B: Blood Capillaries
X C: Sinusoidal Capillaries X D: Lymphatic Capillaries

Blood and lymphatic capillaries

Which of the following is the primary absorption site of a drug given via subcutaneous injection?

> A: Blood and lymphatic capillaries
X B: Epithelia of the upper small intestine X C: Stratum Corneum
X D: Bronchiolar Epithelium

Tablet & Suspension

Which of the following is an example of a dosage form given orally? Select ALL that apply.

> A: Tablet
> B: Suspension X C: IV injection X D: Ointment

Aq solution

Which of the following is an example of a dosage form given as an epidural injection? 5/5

X A: Tablet
> B: Aqueous Solution X C: Suspension
X D: Ointment

If a drug is given via the sublingual route, what is the site of administration?

under the tongue

the drug is converted to a form that can be removed from the body

Metabolism takes place when _________

A: The drug is converted to a form that can be removed from the body X B: The drug is removed from the body
X C: The drug is released from the delivery system
X D: The drug is absorbed

Aq NaCl solution

Pharmaceutical solutions are mostly solids dissolved in a liquid, which is usually water or water combined with other liquids. Which of the following is an example of this type of solution?

X A: Air
X B: Fog
X C: Goldsilver mixture
> D: Aqueous NaCl solution

Aqueous solution.

Which of the following is an example of a dosage form that can be formulated as an epidural injection?

> A: Aqueous Solution X B: Suspension
X C: Tablet
X D: Cream

Between the cheek and gums.

If a drug is given via the buccal route, what is the site of administration?

A: Between the cheek and gums X B: Under the tongue
X C: By mouth
X D: Within bone marrow

basic

Weakly __ drugs tend to dissolve better in the stomach, where more of the drug will be ionized.

X A: Acidic
X B: Polar
> C: Basic
X D: Anhydrous

D: Bioavailability

__________________ can be defined as the fraction of an administered dose of unchanged drug that reaches the 5/5

systemic circulation.

X A: Liberation
X B: Mole Fraction X C: Absorption
X D: Bioavailability

250

How many milligrams of NaCl should be used in compounding the prescription? Report as a whole number. Rx Ephedrine sulfate 1.45 g (E = 0.2) Sodium chloride qs Purified water ad 60 mL Make isoton. sol. Sig. Use as directed

4

If the bioavailability (F) of digoxin in a 1.25 mg tablet is 0.60 compared to the bioavailability (F) of 0.75 in a digoxin elixir (0.25 mg/ml), calculate the dose, in mL, of the elixir equivalent to the tablet. Report as a whole number.

43.5

A patient received a single intravenous dose of 375 mg of a drug substance that produced an immediate blood

concentration of 8.62 ug of drug per milliliter. Calculate the apparent volume of distribution. Report to the tenths

place.

0.202

The molar ratio of s
The molar ratio of sodium acetate to acetic acid in a buffer solution with a pH of 5.76 is 10:1. Assuming the total buffer concentration is 3.7 X 10-2 mol/L, how many grams of acetic acid (m.w. 60) should be used in preparing a liter of the solution? Report to the thousandths place.

10.24

What is the pH of a
What is the pH of a buffer solution prepared with 0.15 M sodium borate and 0.015 M boric acid? The pKa value of boric acid is 9.24 at 25° C. Report to the hundredths place.