Pharmaceutics

Question 1

Which animal insulin is most similar to humans?

Answer 1

Porcine

Question 2

How many amino acid differences are there between human and porcine insulin?

Answer 2

1

Question 3

How many amino acid differences are there between human and bovine insulin?

Answer 3

3

Question 4

How many amino acid differences are there between human and sheep insulin?

Answer 4

4

Question 5

Who helped to solve the potency loss and solubility problems with insulin?

Answer 5

Walden

Question 6

How did walden help to solve the potency loss and solubility problems with insulin?

Answer 6

Recognised the potent material was in a discarded precipitant. Led to process of isoelectric precipitation with standardised purity and potency

Question 7

How was human insulin manufactured?

Answer 7

Combinations of A and B chains individually expressed in E. coli

Question 8

Features of hexamer insulin?

Answer 8

Stable but not biologically active. Minimal diffusion into capillaries

Question 9

Features of dimer insulin?

Answer 9

Biologically active but less stable then hexamer. Limited diffusion into capillaries

Question 10

Features of monomer insulin?

Answer 10

Biologically active but not stable. Rapid diffusion into capillaries

Question 11

What is NPH insulin?

Answer 11

Neutral protamine hagedorn

Question 12

What causes NPH insulin to have a longer action?

Answer 12

Provided as a crystalline suspension of insulin with protamine and zinc

Question 13

What is the only type of insulin which is typically cloudy?

Answer 13

Insulin NPH

Question 14

Why is insulin NPH cloudy?

Answer 14

Due to added crystals

Question 15

Why is zinc used in insulin?

Answer 15

Used as a delaying agent. Size of crystals is proportionate to duration of action

Question 16

Why is insulin glargine long-acting?

Answer 16

One amino acid replaced by two a mini acids at the end of B chain.
Makes it more soluble at acid pH compared to physiological pH
Acid solution microprescipitates after injection due to reduced solubility
Crystals dissolve slowly to release insulin slowly

Question 17

Why is insulin detemir long-acting?

Answer 17

One amino acid omitted from end of B chain and replaced with fatty acid.
Action is extended because it’s altered form make it stick to itself at the injection site.

Question 18

Why is insulin lispro rapid acting?

Answer 18

Lysine and proline residues are switched on C-terminal of the B chain. Modification prevents dimers from forming so injection only contains monomers

Question 19

How was insulin aggregation in continuous subcutaneous insulin infusions resolved?

Answer 19

Using less aggregating insulin such lispro

Question 20

Inhaled insulin has a similar kinetic profile to what type of insulin?

Answer 20

Fast acting

Question 21

Why was inhaled insulin removed from the market?

Answer 21

Poor sales volume due to cost

Question 22

What is viscosity?

Answer 22

An expression of the resistance of a fluid to flow

Question 23

What is a Newtonian fluid?

Answer 23

The viscosity does not change with the shear rate

Question 24

Examples of Newtonian fluids?

Answer 24

Water
Honey
Pharmaceutical dosage forms with high water content

Question 25

Why does the velocity change when it is close to a wall?

Answer 25

It is much lower due to intermolecular interactions (adsorption)

Question 26

Why is it only possible to manufacture certain concentrations of insulin?

Answer 26

The adsorption rate is inversely proportional to the insulin concentration. So if the concentration is too high more will adsorb to the surface of the syringe

Question 27

Reynolds's three regions of flow?

Answer 27

Laminar flow Turbulent flow Transition flow

Question 28

What is laminar flow?

Answer 28

Seen in the low-velocity region Dye formed thin, straight streak down the pipe with no mixing All motion in axial direction Pressure drop per unit length is proportional to flow rate

Question 29

What is turbulent flow?

Answer 29

In high-velocity region Dye was rapidly mixed throughout the pipes Rapid, haphazard motion in all directions along with the axial flow causes mixing of the dye

Question 30

What is transition flow?

Answer 30

Flow is either laminar or turbulent and alternates depending on conditions Conditions can include roughness of pipe wall, equipment vibrations

Question 31

What two forces did Reynolds determine were acting on the flow of fluid?

Answer 31

Inertial (velocity) Viscous

Question 32

What do inertial forces do in fluid flow?

Answer 32

Maintain flow and it's general direction

Question 33

What do viscous forces do in fluid flow?

Answer 33

Retard the general motion of fluid and introduces eddies (swirls)

Question 34

What does a Reynolds number <2100 show?

Answer 34

Laminar flow

Question 35

What does a Reynolds number 2100-4000 show?

Answer 35

Transition flow

Question 36

What does a Reynolds number >4000 show?

Answer 36

Turbulent flow

Question 37

What factors does Reynolds number look at?

Answer 37

Density of fluid Velocity of fluid Diameter of pipe Viscosity of liquid

Question 38

Reynolds number equation?

Answer 38

Fluid density x fluid velocity x diameter ——-———————————————— Fluid viscosity

Question 39

Which forces dominate with a high Reynolds number?

Answer 39

Inertial

Question 40

Which forces dominate with a low Reynolds number?

Answer 40

Viscous

Question 41

Why is Hagen-Poiseuille’s law relate to pharmacy?

Answer 41

A small increase in the radius of a needle can reduce the pressure required to deliver the drug

Question 42

What does a needle gauge need to consider?

Answer 42

A balance between insertion pain and force required to administer the dose effectively

Question 43

What does Hagen-Poiseuille’s law take into consideration?

Answer 43

Radius of capillary Time of flow Pressure difference Length of capillary

Question 44

How to measure viscosity?

Answer 44

Use a capillary viscometer. The time is takes the solution to drop from the start point to the end point

Question 45

What is stability testing used for?

Answer 45

Evidence for how quality of product varies with time Establishes shelf-life Determines storage conditions Determines suitability of containers

Question 46

Factors that can influence chemical stability?

Answer 46

Temperature Light Oxygen Moisture pH Ionic strength Excipients

Question 47

What does ICH stand for?

Answer 47

International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use

Question 48

What is the ICH?

Answer 48

committee that provides the pharmaceutical stability guidelines for industries

Question 49

What is long-term stability testing?

Answer 49

performed for a longer duration of the test period to allow significant product degradation under recommended storage conditions.

Question 50

What is accelerated stability testing?

Answer 50

a means of comparing alternative formula-dons, packaging materials, and/or manufacturing processes in short-term experiments. Usually high temperature studies

Question 51

Uses of accelerated stability testing?

Answer 51

Product development Quickly predict shelf life Variables can include temperature, light, humidity

Question 52

Purpose of the Arrhenius equation?

Answer 52

Explains the effects of temperature on a rate of reaction

Question 53

How much does the speed of a reaction increase with a 10°c rise in temperature?

Answer 53

~2/3 times

Question 54

What do peaks in a chromatogram show?

Answer 54

A separated component

Question 55

What is the time it takes for a sample to come off a chromatography column?

Answer 55

Retention time

Question 56

Two main ways to interpret a chromatogram?

Answer 56

1) peak height 2) peak area

Question 57

Five principles for the procurement and supply of specials?

Answer 57

1) understand the patient's experience and make a shared decision 2) establish the optimal treatment 3) identify a preparation and supplier 4) monitor and review the need for the special 5) ensure effective governance

Question 58

What is the pharmacist responsible for when dealing with UK specials?

Answer 58

Assessing clinical suitability Checking manufacturer has an appropriate license Ensuring product meets purchasing specification Assess evidence that supports the formulation and shelf life

Question 59

What is the pharmacist responsible for when dealing with extemporaneous preparations?

Answer 59

Assessing clinical suitability Ensuring medicine is made in a registered pharmacy Ensuring product meets purchasing specification Assess evidence that supports the formulation and shelf life

Question 60

What is a normal phase HPLC assay?

Answer 60

Mobile phase is non-polar Stationary phase is polar

Question 61

What is a reverse phase HPLC assay?

Answer 61

Mobile phase is polar Stationary phase is non-polar