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PHARM212: Pharmaceutical Science > Lab Assessed > Flashcards

Lab Assessed Flashcards

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1
Q

Explain why the concept of ‘intermolecular forces’ is relevant to pharmaceutical practice

A

Intermolecular forces are the forces which mediate interaction between molecules, including forces of attraction or repulsion

Important for understanding and achieving stable formulations that will act in a reproducible manner on the body

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2
Q

Describe repulsive forces

A

All molecules have an electron cloud. When such molecules are brought closer together (decreasing intermolecular distance), these like-charged cloud repel (repulsion)

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3
Q

Identify 3 common types of attractive forces and state whether or not they are stronger or weaker than covalent, ionic or metallic bonding

A
  • Ion-dipole
  • van der Waal’s (dipole-dipole and London dispersion)
  • Hydrogen bonding

Intermolecular forces of attraction are weaker than intramolecular forces of attraction so they are weaker.

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4
Q

Explain the effect temperature and pressure exert on gas molecules

A

Increasing temperature increases the amount of energy in the system, causing the gaseous molecules to move at a greater speed.

Increasing pressure increases the number of molecular collisions on the walls of the container.

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5
Q

Identify and explain the two parameters that can be adjusted to cause the liquefaction of gas

A

Decreasing temperature decreases kinetic energy causing the gaseous molecules to move slower.

Increasing pressure results in the molecules becoming closer together.

By adjusting these two parameters in such a way, the attractive forces of the gas molecules can bring them together to condense into a liquid.

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6
Q

Explain the significance of critical temperature and critical pressure.

A

Critical temperature is the temperature above which the liquid state can no longer exist

Critical pressure is the pressure required to liquefy gas (assuming critical temperature)

Both critical temperature and critical pressure make up the critical point.

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7
Q

Define vapour pressure and discuss how different vapour pressures affect equilibrium

A

Vapour pressure is the pressure exerted by molecules that have evaporated.

When the actual vapour pressure (P) is below the equilibrium vapour pressure (Peq), the liquid will evaporate to shift towards equilibrium.

When P = Peq, there is an equal amount of evaporation and condensation (note: the system is not static)

When P > Peq, molecules in a gaseous state condense into a liquid state to decrease the vapour pressure to shift towards equilibrium.

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8
Q

Identify and define the two types of solids

A

Crystalline - solids that are structurally ordered forming a crystal lattice

Amorphous - solids without order

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9
Q

Compare and contrast crystalline and amorphous solids with reference to:

  • Geometry
  • Melting point
  • Latent heat of fusion
  • Directional properties
A

Geometry - crystalline solids have defined shape and symmetry

Melting Point - crystalline solids have defined melting points whereas amorphous solids tend to melt over a range of temperatures

Latent Heat of Fusion - Fixed for crystalline solids, not for amorphous solids

Directional Properties - crystalline solids are anisotropic, amorphous solids are isotropic

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10
Q

Explain the concept of ‘liquid crystals’

A

Liquid crystals are systems in which there is some degree of molecular order while maintaining an overall fluid state (e.g. lipid bilayer)

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11
Q

Explain the concept of ‘birefringence’ and state which types of substances are most likely to have it

A

Birefringence is an optical property in which a single ray of polarised light entering an anisotropic material is split into two rays, travelling at different speeds and different directions.

Crystalline substances have different concentrations of atoms along different axes (anisotropic) and can exhibit birefringence.

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12
Q

Identify and explain the state change that occurs when the temperature is changed and pressure is lower than the triple point

A

When temperature changes and pressure is lower than the triple point, sublimation occurs. Sublimination is the state change from solid to a gas without first changing to liquid

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13
Q

Explain the different components of the phase rule (F = C-P+2)

A

F = degrees of freedom: the number of variables that must be fixed to define a system.

C = number of components: a distinct chemical species in a system.

P = number of phases present: a physically distinct portion of a system separated by boundaries.

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14
Q

Explain the differences in degrees of freedom when finding a point vs. a line

A

When finding a point, we need two degrees of freedom. In other words, we need two variables to be fixed (pressure and temperature).

When finding a line, we need one degree of freedom. This means that we need one fixed variable (pressure OR temperature).

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15
Q

State the number of components and phases present in a solution of alcohol+water vs. ice+water

A

Alcohol+water = 2 components, 2 phases

Ice+water = 1 component, 2 phases

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16
Q

Describe the graph appearance of a two-component system containing liquid phases and a two-component system containing solid and liquid phases.

A

Two-component liquid phases: A parabolic curve that defines conditions whereby a single liquid phase or two-liquid phase exists. The closer the two liquids are to a 50:50 ratio, the greater the temperature needed to produce a single liquid (miscible) phase.

Two-component solid-liquid phase: separated into a solid phase and a liquid phase. In the liquid phase, a declining curve that intersects an increasing curve. The more disproportional the ratio of solids are, the greater the temperature needed to produce a single liquid phase.

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17
Q

Describe the ‘eutectic point’

A

The lowest temperature at which liquid can exist in a two-component system containing solid and liquid

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18
Q

Describe the appearance of a three-component diagram

A

Triangle with each corner designated to the 100% component of one substance and 0% component of another substance.

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19
Q

Define ‘supercritical fluids’

A

State generated when pressure and temperature exceed the critical point. The resulting product has liquid-like density and gas-like viscosity and diffusivity.

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20
Q

Define a polymorph

A

A compound that can crystallise in different forms

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21
Q

Define a solvate/hydrate

A

A compound formed by the interaction of a solvent and a solute.

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22
Q

Describe what is meant when a material is called ‘lyotropic’

A

A material is lyotropic when it forms liquid crystal phases upon the addition of a solvent.

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23
Q

Describe the difference between anisotropy and isotropy

A

Anisotropy - a difference in chemical property when measured along difference axes

Isotropy - the physical properties are identical in all directions

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24
Q

Assess the differences in properties between crystalline and amorphous substances

A

Crystalline:

  • sharp melting point
  • low solubility
  • low dissolution rate
  • low bioavailability
  • high stability

Amorphous:

  • broad melting point
  • high solubility
  • high dissolution rate
  • high bioavailability
  • low stability
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25
Q

Define ‘polymorphism’ and discuss the chemical and physical differences in polymorphs

A

Polymorphism - the ability of a solid compound to exist in more than one crystal lattice.

Polymorphs are chemically identical but have varying physical properties (solubility, melting point, dissolution rate, density, chemical and physical stability, hygroscopicity, etc.).

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26
Q

Describe what is meant by an ‘interface’ and explain the difference between a surface and an interface

A

An interface is a boundary between two immiscible phases.

A surface can only exist with phase boundaries involving gas (e.g. gas-solid, gas-liquid)

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27
Q

Explain the significance of interfaces on pharmaceutics

A

Formulation stability

Permeation process

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28
Q

Discuss the differences between cohesive forces and adhesive forces

A

Cohesive forces - forces of attraction between molecules of the same phase

Adhesive forces - forces of attraction between molecules of one phase with molecules of another phase.

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29
Q

Explain how surface tension is produced

A

Surface tension can be produced in vapour-liquid interfaces. This is because the surface liquid molecules have cohesive forces existing between other molecules either adjacent or below (bulk liquid molecules have cohesive forces in all directions). As a result, there is a net inward pulling force pulling towards the bulk, causing the liquid surface to contract, leading to surface tension.

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30
Q

Explain the Du Noüy Ring Method measures

A

The force necessary to detach a platinum-iridium ring immersed at the surface or interface is proportional to the surface or interfacial tension, respectively

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31
Q

Define ‘surfactant’

A

Surfactants are compounds that lower the surface tension between two liquids, a liquid-gas, or between liquid-solid by interacting with both phases of a system (possessing lipophilic and hydrophilic components)

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32
Q

Describe the orientation of surfactant molecules at a water-air surface

A

Polar heads facing the liquid phase and non-polar tails facing the vapour phase. Surfactant molecules at low concentrations can dissolve in water (due to polar component), however, at a certain concentration the molecules will ‘line up’ at the water-air surface and orient themselves in such way (i.e. saturation).

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33
Q

Describe ‘micelles’

A

Micelles are structures composed of surfactant molecules and are formed by increasing the surfactant concentration beyond the CMC point.

Micelles can hold oils in water and water in oils depending on the orientation of the surfactant molecules (lipophilic inside, hydrophilic outside or hydrophilic inside, lipophilic outside respectively).

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34
Q

Discuss changes in surface tension, surfactant activity and micelle formation when surfactant concentration is increased

A
  1. ) Surface tension remains constant - surfactant molecules present in the solution are relatively soluble and exist within the solution. Surfactant may line up at the surface, however, it is not enough to cause an effect on the surface tension.
  2. ) Surface tension decreases - once concentration of surfactant increases, water begins to interact more strongly with the lipophilic tails causing surfactant to line up at surface, surface tension begins decreasing to the CMC point.
  3. ) Surface tension plateaus - beyond the CMC point, an increase in surfactant concentration will see the formation of micelles as surface has been saturated.
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35
Q

Compare and contrast surfactants in water-air vs. in two immiscible liquids

A

In both water-air and liquid-liquid and at above a concentration, surfactant molecules will begin lining up at the surface to reduce surface tension. However, as micelles form in the water in a water-air system, in the liquid-liquid system micelles form in both. Furthermore, the micelles in each of the two liquids will be structured differently, one with hydrophilic heads on the outside and the other with lipophilic tails on the outside instead.

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36
Q

Discuss the applications of surfactants

A

Since many drugs are lipophilic, and oral liquids tend to be aqueous, surfactants allow drugs to reside in aqueous solutions.

Without surfactants, lipophilic drugs are prone to aggregating (clumping) and produce air pockets. Therefore, surfactants act as a coating over the drug which prevents the molecules from interacting (i.e. clumping).

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37
Q

What is HLB

A

HLB stands for ‘hydrophilic-lipophilic balance’ and is the measure of how hydrophilic or lipophilic a surfactant is

High HLB = high water solubility
Low HLB = high fat solubility

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38
Q

In the HLB equation…

rHLB = (HLB(a) x a) + (HLB(b) x b

…‘a’ and ‘b’ represent what?

a. ) amount of each surfactant
b. ) concentration of each surfactant
c. ) proportion of each surfactant
d. ) surfactant constant

A

c.) proportion of each surfactant (adding to 1)

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39
Q

Define a ‘tablet’

A

A compressed solid dosage form that contains drugs with or without excipients

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40
Q

State the advantages of tablets

A
  • Precise dose
  • Easy to use (everyone knows how to use it)
  • Convenient to carry
  • Large scale manufacturers (machines can mass produce tablets easily)
  • Low cost of excipients
  • Taste masking
  • Complex designs possible
  • High stability (solid - does not diffuse, evaporate, easier to store)
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41
Q

State the disadvantages of tablets

A
  • Difficult to swallow (children, elderly, patients with conditions interfering with swallowing)
  • Limited dose flexibility (1 tablet, half a tablet but can’t administer e.g. 1/5 a tablet)
  • Difficult to compress some drugs (e.g. amorphous)
  • Special packaging required (e.g. hygroscopic or oxygen sensitive drugs)
  • Bioavailability issues (dissolution necessary)
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42
Q

Explain the process of tablet compression

A
  • Drug powder is placed in a hopper which is connected to a feed tube
  • Feed tube releases small amounts of powder to the die
  • The upper punch will then compress the powder into a tablet
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43
Q

State when ideal flow and compression properties are seen in particles

A

When particles are sized 0.2-0.5 mm

44
Q

Identify the THREE types of tablet compression

A
  • Direction compression
  • Dry granulation
  • Wet granulation
45
Q

Explain direct compression (include advantages and disadvantages)

A

Direct compression is the cheapest and fastest method of tablet compression. It involves taking the powder mix and compressing it directly.

Another advantage is that is can be used for moisture- and heat-sensitive drugs.

Disadvantages include a heterogenous powder mixture, limited drug concentration and a weak tablet.

46
Q

Explain granulation

A

Granulation is the process of narrowing the particle size range (to increase flowability) by forming granules prior to compression.

Granulation provides a tablet with a homogenous powder mixture capable of high drug concentrations.

47
Q

Discuss under which circumstances would dry vs. wet granulation be appropriate

A

Dry granulation has an ‘intermediate’ cost and speed whereas wet granulation is expensive and slow.

For moisture- and heat-sensitive drugs, we would need to use dry granulation. This is because wet granulation involves wetting and then heating the drugs which some drugs cannot undergo.

However, to achieve the ‘strongest’ tablet, wet granulation is used.

48
Q

Explain the purpose of a ‘diluent’ and provide an example

A

Diluents are fillers used when the dosage itself is inadequate to produce an entire bulk tablet.

It can also reduced irritation and is usually clean, cheap, non-toxic, non-reactive, aesthetic, and compressible.

Example: starch, lactose

49
Q

Explain the purpose of a ‘binders and adhesives’ and provide an example

A

Binders and adhesives ensure that the tablet stays intact (i.e. acts as a glue).

Example: acacia

50
Q

Explain the purpose of a ‘lubricants and glidants’ and provide an example

A

Lubricants prevent the tablet from adhering to surfaces (especially the die/punches) and improve the powder/granule flow.

Glidants prevent friction between particles to improve powder/granule flow.

Example (both): talc

51
Q

Explain the purpose of a ‘disintegrants’ and provide an example

A

Disintegrants ensure that tablets will break down once it is in contact with water or aqueous fluids in the GIT.

Example: starch

52
Q

Explain the purpose of a ‘tablet coating’ and provide an example

A

Tablet coatings are added to protect tablet contents and/or protect the body from the tablet. Additionally, they can also be used to make the tablet easier to swallow (aesthetics, flavouring).

53
Q

Explain the purpose of a ‘flavouring agent’ and provide an example

A

Flavouring agents are used to mask the taste of certain drugs. This is especially important in tablets that dissolve before swallowing.

54
Q

Identify the different types of tablets

A
  • Orally ingested
  • Used in oral cavity
  • Non-oral
  • Prepare solutions
55
Q

Discuss, under which circumstances, would standard or multiple compressed orally-ingested tablets be appropriate.

A

Single compression is simple and fast but is unable to combine multiple actives in a single tablet.

Multiple compression allows for the compressive of actives in different layers, subsequently combining them in a single tablet.

Single compression is preferred when a tablet only has one active component. However, multiple compression is preferred when multiple active components are present in a single tablet.

56
Q

Describe delayed release tablets and state what excipients are needed to make them.

A

Delayed release tablets are two layer tablets where the external layer releases drug immediately while the internal layer releases drug slowly.

An enteric coating can be used to ensure that a drug is not released until it reaches a specific part in the GI tract.

57
Q

Explain when it may be appropriate to administer chewable tablets and state what property must be considered.

A

Chewable tablets may be administered to children who have difficulty swallowing normal tablets.

Since tablets are being chewed, it is important to consider the flavouring to ensure palatability.

58
Q

Explain why it is important to test raw materials before they are made into a tablet and give examples of what methods we may use to do so.

A

Because we must ensure that the active ingredient and the excipients are pure.

Example: melting point, thin-layer chromatography, IR, MS

59
Q

State the three different ways a tablet can ‘break’

A
  • Capping (partial/full removal of crown of tablet)
  • Lamination (breakdown of layers)
  • Cracking/chipping (cracks)
60
Q

Discuss why testing tablet ‘hardness’ is important, and include the approximate range of force that a typical tablet can endure.

(Extra: discuss if we should expect chewable and sustained release tablets to have more or less force endurance)

A

Tablets can be exposed to mechanical shock during manufacturing, packaging, transport or handling.

4-10 kg/cm2

Since chewable tablets need to be chewed and relatively easy to breakdown, it should have lower force limit (3 kg/cm2).

Sustained release tablets are made to remain intact in harsher conditions, so we can expect a greater force limit (10-20 kg/cm2).

61
Q

Discuss the difference between tablet hardness and tablet friability

A

Hardness is the amount of force required to break a tablet whereas friability is the tendency of a table to chip/crumble.

A highly friable tablet is more prone to chipping.

62
Q

Weight variation is a parameter used to assess tablet quality. Explain how this is done.

A

Determining weight variation can help establish tablet consistency. This can be done by weighing 20 tablets individually and calculating the average weight. In order for a set of tablets to be considered consistent, there must be a deviation of no more than 20%.

63
Q

Mechanical strength and weight variation are two parameters used to measure tablet quality. Identify five other methods.

A
  • Visual defects
  • Content uniformity
  • Disintegration
  • Dissolution
  • Stability testing
64
Q

Describe how reactions occur and state the factors affective rates of reaction.

A

Reactions occur when molecules collide with each other with sufficient energy and the correct orientation.

Factors:

  • Temperature
  • Light
  • Catalyst
  • Concentration
65
Q

Describe unimolecular reactions

A

Unimolecular reactions are reactions that involve a change in only one molecule. This can result in:

  • one molecule decomposing into two or more atoms/molecules
  • one molecule isomerising into a molecule with a different structure
66
Q

Describe bimolecular reactions

A

Reactions that involve two molecules that can:

  • associate (A + B → AB)
  • exchange (A + B → C + D)
67
Q

Reaction rate is given by the expression dc/dt. Describe what dc/dt means.

A

The decrease of concentration over a (extremely small) time interval.

68
Q

State the integrated rate laws of zeroth, first and second order reactions

A

Zero: [A] = [A]0 - kt

First: ln[A] = ln[A]0 - kt

Second: 1/[A] = 1/[A]0 + kt

69
Q

State the half-life equations of zeroth, first and second order reactions

A

Zero: t(1/2) = [A]0/2k

First: t(1/2) = 0.693/k

Second: t(1/2) = 1/k[A]0

70
Q

When the concentration of one reactant is much greater than the other, what order reaction is it classified as, and what is the assumption we make?

A

Pseudo-order reaction.

Assumption: that concentration change in the greater reactant is negligible and hence, we treat the reaction as a first-order reaction.

71
Q

Explain how an increase in temperature increases rate of reaction.

A

At higher temperatures, reactant molecules have more kinetic energy, move faster, and collide more often with greater energy

72
Q

State the Arrhenius equation

A

k = Ae^(-Ea/RT)

73
Q

Explain how concentration of reactants affect rate of reaction.

A

As the concentration of reactants increase, so does the likelihood of the reactant molecules colliding

Kinetic-molecular theory: states that the number of collisions per second depends on the number of particles per litre (i.e. concentration)

74
Q

Explain how solvents affect rate of reaction

A

Neutral molecules: use solvents that have similar polarity to the reactant (e.g. polarity of reactant < product, use low polar solvent)

Ionic molecules: use similarly charged solvent to reactant to increase reaction rate.

75
Q

Explain how catalysts affect rates of reaction

A

Catalysts speed up reactions by changing the mechanisms. This is done by decreasing the activation energy by providing an ‘alternate pathway’.

Catalysts are not consumed in the reaction and only a small quantity is needed to affect the rate of reaction of a large reactant.

76
Q

State the two types of catalysts

A

Heterogenous - catalyst and reactants form separate phases (e.g. solid in liquid mixture).

Homogenous - catalyst and reactants are in the same phase.

77
Q

State the 4 processes that affect stability

A
  • Hydrolysis
  • Oxidation
  • Isomerisation
  • Photolysis
78
Q

State 4 environmental factors that affect stability

A
  • Heat
  • Oxygen
  • Moisture content
  • Light
79
Q

Define hydrolysis and explain how it can be prevented in drugs.

A

Hydrolysis is the chemical breakdown of a compound due to reactions with water.

Prevention:

  • Use buffers to prevent pH based hydrolysis
  • Adding desiccants (substance that absorb water)
  • Changing formulation
  • Modifying solubility
80
Q

Which functional groups are more prone to hydrolysis?

A

Ester and amides.

81
Q

Define oxidation and state one factor affecting the rate of oxidation.

A

A reaction with oxygen to produce an electronegative molecule (either through removal of positive atom or electron or additional of electronegative atom).

Factors affecting:

  • temperature (increases)
  • fatty acids (increases)
  • state of compound
  • degree of (un)saturation
  • dilution (decreases rate)
82
Q

Provide a method to reduce oxidation.

A
  • Air-tight packaging to prevent oxygen contacting product
  • Include antioxidants (e.g. ascorbic acid)
  • Include reducing agent
83
Q

Define isomerisation

A

The conversion of an active drug into a less active state

84
Q

Explain photolysis and state a method of preventing photolysis.

A

Photolysis is the decomposition of molecules by light. Molecules can absorb light and become excited. This must occur at the right frequency. The energy absorbed by the molecules may be sufficient to reach activation energy and cause degradation or reactions with other components.

Photolysis can be prevented by packaging compounds in bottles made with special brown glass to protect from light.

85
Q

Describe hard capsules

A

Solid dosage forms comprising of a physiologically inert hard exterior shell filled with therapeutic substance

86
Q

State 4 methods of quality testing hard capsules

A

Disintegration
Dissolution
Content uniformity
Weight variation

87
Q

Describe what is meant by ‘bloom strength’

A

Bloom strength is the measurement of the strength of a gel (i.e. the amount of force needed to penetrate the surface of gelatin)

88
Q

Desiccants are often found in capsule bottles. Explain why.

A

Hardshell capsules need to have a moderate amount of water. When the moisture content is below 12%, the capsule can be too brittle. On the other hand, capsules with a moisture content above 18% can be too soft. Hence, it is important to manage the levels, and therefore, the intake/release of moisture.

89
Q

Describe soft gels (soft capsules)

A

Are one-piece hermetically sealed soft shells

90
Q

State the advantages of soft gels

A
  • Can incorporate oily drugs in liquid form
  • Size and shape flexibility
  • Accurate dosing of low concentration drugs
  • Manufacturing process devoid of particulates
91
Q

State the disadvantages of soft gels

A
  • Containing interior liquid makes capsules less stable
  • Difficult to incorporate water soluble drugs
  • Tough to extract contained drug for compounding
92
Q

State the advantages of hard shell capsules

A
  • Offer advantages of tablet coating
  • Can co-formulate incompatible substances
  • Can incorporate drug as powder or granules
  • Can readily retrieve drug for extemporaneous compounding
93
Q

State the advantages of tablets

A
  • Rapid large scale manufacturer
  • Low-cost manufacture
  • Complex designs possible
  • Can be halved if uncoated/non-specialised
94
Q

State 3 unofficial tests for tablets

A
  • General appearance
  • Uniformity of diameter and thickness
  • Resistance to crushing (hardness)
95
Q

Explain the hardness test

A

The test measures the strength of the tablet to withstand the pressure applied.

Hardness can affect the disintegration and friability.

96
Q

State the 5 official tests for tablets

A
  • Uniformity of weight
  • Friability
  • Disintegration
  • Content uniformity (assay)
  • Dissolution
97
Q

Uniformity of weight is an official method of quality testing tablets. Explain how it is conducted.

A

By taking 20 tablets and weighing them individually. Calculate the average and compare this value to each tablet.

No more than 2 tablets should deviate by more than a certain percentage. and non should deviate by twice that percentage.

98
Q

Friability is an official method of quality testing tablets. Explain how it is conducted.

A

The test measures the ability of the tablet to withstand abrasion after a tumbling motion (using friabilator). The maximum weight loss acceptable is <1%. If above 1%, repeat twice and take the mean of the 3 measurements.

Tablets that are cracked or broken fail the test.

99
Q

Disintegration is an official method of quality testing tablets. Explain how it is conducted.

A

Measuring the breakdown of a dosage form. Test is conducted with 6 tablets immersed in water at a certain temperature and is given a specified amount of time to disintegrate completely.

Failure to disintegrate within this time will call for 12 additional tablets to be tested.

100
Q

Assay (uniformity of content) is an official method of quality testing tablets. Explain how it is conducted.

A

The test of the determination of the amount of an active ingredient in a drug product.

101
Q

State the 4 methods of measuring the surface tension

A
  • Du Nuoy Ring Method
  • Sessile Drop Method
  • Capillary Rise Method
  • Wilhelmy Plate Method
102
Q

Explain the Sessile Drop method

A

A droplet of a liquid is placed on a surface where its contact angle is measured. High contact angle indicates cohesive > adhesive force (i.e. high surface tension) and low wetting. And vice-versa.

103
Q

Explain the Capillary Rise method

A

A capillary (thin tube) is immersed in a liquid. The height at which the liquid rises in the tube is inversely proportional to the amount of surface tension. Liquids that rises in the capillary above their surrounding liquid indicates cohesive < adhesive forces (i.e. low surface tension) and are concave at the top.

A liquid that enters the tube but remains lower than its surroundings indicates cohesive > adhesive (i.e. high surface tension) and have a curve shape at the top.

104
Q

Explain the Wilhelmy Plate method

A

A plate is immersed in a liquid of interest and pulled upwards. The amount of force required to pull the plate is proportional to the surface tension. This is because liquids with strong cohesive forces will have molecules that are more strongly bound to each other. As a result, when the molecules in contact with the plate get pulled up, the other molecules also get pulled up, requiring more force to be applied to the plate.

105
Q

State 4 ways to quality test softgels

A
  • Ribbon thickness and seal thickness stay constant
  • Fill matrix weight and capsule weight
  • Soft-gel moisture level and capsule hardness
  • Bloom strength

PHARM212: Pharmaceutical Science (2 decks)

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