Pharmaceutical Sciences 3 Exam 1

Front 1

Preformulation Studies

Back 1

1.) Physical description

2.) Microscopic examination

3.) Melting point

4.) Particle size

5.) Polymorphism

6.) Solubility

7.) Dissolution

8.) Membrane permeability

9.) pKa/dissociation constants

Front 2

How much does it cost to make a drug?

Back 2

$1 billion (1.5 billion)

Front 3

About ________ drugs have to be screened before ONE NEW DRUG makes it to market

Back 3

10,000

Front 4

The major difference between preclinical and clinical drug development is that clinical testing involves evaluation in __________.

Back 4

Humans

Front 5

To formulate a drug into a dosage form, we need additional products called ________.

Back 5

Excipients

Front 6

As the particle size of a drug powder goes down, its total _______ _______ goes up, and dissolution rate also increases.

Back 6

Surface area

Front 7

A drug has two polymorphic forms, form I and form II. The melting point for form I is 79 C and that of form II is 114 C

Which form is likely to have higher solubility?

Back 7

Form I

Front 8

A drug has two polymorphic forms, form I and form II. The melting point for form I is 79 C and that of form II is 114 C

Which form is likely to have greater stability?

Back 8

Form II

Front 9

What characteristics can polymorphism impact?

Back 9

1.) strength of the material

2.) solubility, dissolution

3.) melting point

4.) stability

Front 10

Solubility is a ________ property of a material, whereas _______ is a kinetic property.

Back 10

Thermodynamic, dissolution

Front 11

The _________ coefficient is a good measure of the membrane permeability of a drug molecule.

Back 11

Partition

Front 12

When a drug is added to an equal mixture of an organic phase (typically octanol) and water, the ratio of concentrations in which the drug distributes itself between these two phases is the Partition ________.

Back 12

Coefficient

Front 13

A drug has a logP value of 6. Would this drug be hydrophilic or hydrophobic? How would you know?

Back 13

Hydrophobic

Use the partition coefficient P=Coctanol/Cwater

C6/C1 = 10^6 time more soluble in octanol than water

Front 14

What is the BCS system of drug classification? Describe each of the four classes with respect to solubility and permeability.

Back 14

Solubility vs Partitioning

Class I: High permeability and High solubility

Class II: High permeability and Low solubility

Class III: Low permeability and High solubility

Class IV: Low Permeability and Low solubility

Front 15

Which class is most amenable to alteration by preformulation studies?

Back 15

Class II

Front 16

Which class is least likely to make it to the market due to issues pertaining to bioavailability?

Back 16

Class IV

Front 17

What is the ionic product of water? From this value, derive an equation for pH

Back 17

Kw = [H3O+][OH-] = 1 x 10^-14 mole/liter (neutral because each concentration is 7)

Front 18

The neutral pH of water is 7.0 only when the temperature is ________.

Back 18

25 C

Front 19

When the temperature increases, the neutral pH of water _________.

Back 19

Decreases

Front 20

What info does microscopy tell us?

Back 20

1.) Crystal structure

2.) Particle size

3.) Particle size distribution

4.) Particle shape

Front 21

What factors can polymorphism affect?

Back 21

1.) Strength of the material

2.) Solubility, dissolution

3.) Melting point

4.) Stability

Front 22

Factors that affect solubility

Back 22

Temperature

Particle size

Polymorphism (melting point)

Front 23

Factors that affect dissolution

Back 23

Surface area of solid material

Solubility of the drug in dissolution fluid

Volume of the liquid

Stirring (other forms of mechanical agitation)

Front 24

Diffusion is the flow of mass from a _______ ________ to a low concentration

Back 24

High concentration

Front 25

The mass flux is defined as mass flow divided by ______ and ________.

Back 25

Area and time

Front 26

Define the terms in Fick’s first law of diffusion

Back 26

J = flux

D = diffusion coefficient of the solitude in cm2/sec

dc = difference in concentration

dx = difference in position (units of distance)

Front 27

Units of diffusion coefficient?

Back 27

cm2/sec

Front 28

The equation that allows calculation of Diffusion Coefficient (D) from dissolution testing is the ________ and ________ equation.

Back 28

Noyes and Whitney

Front 29

True or False?

The diffusional boundary layer (h) is a hypothetical layer that explains deviations from Fick’s laws.

Back 29

True

Front 30

The USP disintegration test is conducted at ______ C to simulate conditions of body temperature.

Back 30

37

Front 31

Effervescent Salts

Back 31

Consists of an acid and a base (in water, acid + base = salt + CO2)

Front 32

Dentifrices

Back 32

Powders used to clean teeth, use of surfactants and abrasives (calcium carbonate)

Front 33

Insufflations

Back 33

Intended for application to body cavities (tooth socket, ear, nose, throat)

Front 34

Powder aerosols

Back 34

Pressurized in a “push button” container (deodorants)

Front 35

Douches

Back 35

Intended to be dissolved in water prior to use as antiseptics or as cleansing agents for a body cavity

Front 36

Advantages of powders

Back 36

1.) wide choice of ingredients

2.) more stability than solution

3.) large surface area, rapid absorption

4.) ease of administration

5.) allow manipulation of dose

Front 37

Disadvantages of powders

Back 37

Taste

Exposure to atmospheric moisture and oxygen

Front 38

The anderson pipet method may be used to determine the particle ______ and size _______ for a powder dosage form.

Back 38

Shape, characterized

Front 39

Irregular powder particles can be approximated as _______, ______, and _________

Back 39

Spheres, rods, and discs

Front 40

The flow properties of powders may be measured using the angle of ______

Back 40

Repose

Front 41

True density = mass/?

Back 41

True volume

Front 42

Bulk density = mass/?

Back 42

Bulk volume

Front 43

Void volume =?

Back 43

(Vbulk - V)/Vbulk

Front 44

Bulk density is always lower than or equal to the true density?

Back 44

False! Based on volume

Front 45

The polymer associated with human skin and bones is _______

Back 45

Collagen

Front 46

________ was the first to propose the structure of a polymer in 1922.

Back 46

Herman Staudinger

Front 47

The molecular weight of synthetic polymers cannot be expressed as a single number

Back 47

True.

It has to be an average

Front 48

The weight average molecular weight (Mw) is always greater than or equal to number average molecular weight (Mn)

Back 48

True

Front 49

The ratio of Mw to Mn is known as _______ or Pd

Back 49

Polydispersity

Front 50

Pd can be expressed as ______ average or _______ average molecular weight. The ratio of the two is termed ________

Back 50

Mn, Mw, polydispersity

Front 51

What are the two main components to studying the flow of materials and what are their units?

Back 51

Stress - force applied per unit cross sectional area (F/A)

Strain - deformation produced (change in length over time)

Front 52

What are the units of viscosity?

Back 52

g/cm x sec

Front 53

List 3 types of Newtonian flow behavior

Back 53

Simple plastic or pseudo plastic

Dilatant

Thixotropic

Front 54

Instrument to measure Newtonian material?

Back 54

Capillary viscometers (Ostwald viscometers)

Front 55

Instrument to measure non Newtonian flow?

Back 55

Cone and plate viscometer

Front 56

_______ is a special case of time dependent shear thinning behavior that is particularly useful in formulating disperse systems for pharmaceutical applications

Back 56

Thixotropic flow

Front 57

The typical size of a course dispersion is________ micrometers

Back 57

10-50

Front 58

Suspensions as a rule consist of saturated solutions of the dispersed phase suspended in a dispersion medium

Back 58

True

Front 59

List 3 advantages of using a suspension over a tablet dosage form

Back 59

Poorly soluble drugs

Taste masking

Dose flexibility

Front 60

The velocity of settling in Stokes law is a special type of velocity termed as ______ velocity (v). v is directly proportional to ______ and ________gradient and inversely proportional to ______

Back 60

Terminal, diameter, density, viscosity

Front 61

List 3 mechanisms of instability in suspensions

Back 61

Aggregation (particles come together and stuck becoming heavier)

Caking

Crystal (or particle) growth

Front 62

Flocculation is a mechanism of controlled aggregation with the primary goal of preventing ______

Back 62

A cake

Front 63

________ are examples of flocculating agents

Back 63

Electrolytes, polymers, surfactants

Front 64

List 3 methods to determine instability in suspensions and emulsions

Back 64

Particle size measurements using microscopy

Determination of sedimentation rate

Subjecting to freeze-thaw cycles

Front 65

A suspension degrades by zero order even though a drug may degrade by first order

Back 65

True

Front 66

List 2 pharmaceutical applications of emulsions

Back 66

Delivery of oils/oil soluble drugs (oral, emollients, IV, fatty acids)

Formulations

Front 67

Emulsifying agent in milk

Back 67

Protein caesin

Front 68

List the emulsifying agent in mayonnaise

Back 68

Egg yolk (protein lecithin)

Front 69

List the theories that can explain the mechanism by which surfactants stabilize emulsions

Back 69

Surface tension theory

Oriented wedge theory

Interfacial theory

Front 70

The partition coefficient is critical in determining preservative concentration in an emulsion. Explain.

Back 70

When a preservative is added into oil, you need the phase volume ratio and partition coefficient because some of the preservative will partition into the oil and it will not work (contamination)

Front 71

Microemulsions tend to be thermodynamically _____

Back 71

Stable

Front 72

The important components of an aerosol include a pressurized package, a product concentrate, and a _________

Back 72

Propellant (liquid gas)

Front 73

The particle size range that can carry a drug into the alveoli is roughly 0.4-1.0 microns

Back 73

True

Front 74

Aspect conditions are maintained in aerosols which limits contamination

Back 74

True