Block3 Lecture3

Question 1

How are aerosols classified?

Answer 1

application & energy source

Question 2

What are the energy sources for aerosols?

Answer 2

1) biomechanical, 2) compressed gas, 3) volatile liquid propellant

Question 3

Define aerosol.

Answer 3

a suspension/dispersion of small droplets/solid particles in a gas medium

Question 4

What are the applications for aerosols?

Answer 4

surface sprays, pulmonary aerosols, foams

Question 5

what is a foam?

Answer 5

dispersion of gas in a liquid medium

Question 6

what drug formulation is employed in a biomechanical pump?

Answer 6

aqueous or hydroalcoholic suspension or emulsion of low viscosity

Question 7

describe the entities present in a compressed gas aerosol formulation.

Answer 7

aqeuous solution, N2/CO2 under high pressure. No O2

Question 8

What are examples of volatile liquid propellants?

Answer 8

HFAs or low-MW hydrocarbons (butane)

Question 9

What are the 2 HFAs employed in aerosols?

Answer 9

tetrafluoroethane & heptafluoropropane

Question 10

How do the densities of HFAs compare with H2O?

Answer 10

H2O < TFE < HFP

Question 11

What structural components are consistent across volatile liquid propellant aerosols?

Answer 11

1) valve/actuator, 2) propellant + drug, 3) fixed feed tube

Question 12

What are the two types of volatile liquid propellant systems?

Answer 12

2-phase & 3-phase

Question 13

Describe the entities present in a 2-phase volatile liquid propellant system.

Answer 13

solid drug dispersed in propellant

Question 14

Describe the entities present in a 3-phase volatile liquid propellant aerosol system.

Answer 14

drug dissolved in water + propellant

Question 15

What kinds of materials are used to package aerosols with biomechanical energy input?

Answer 15

plastics

Question 16

What kinds of materials are used to package aerosols with chemical energy input?

Answer 16

tin-plate, Al, or glass

Question 17

What are the packaging requirements for aerosoles?

Answer 17

solution cannot leach!!

Question 18

What are the key factors in drug formulation to maximize effect?

Answer 18

1) particle size, 2) propulsion & inhalation, 3) clearance mechanisms, 4) education by pharmacist

Question 19

What is the surface area for drug permeation in the pulmonary delivery?

Answer 19

200 m2

Question 20

How many bifurcations are present in the bronchi?

Answer 20

17-23

Question 21

What is the conducting airway?

Answer 21

trachea to terminal bronchioles

Question 22

trachea diameter?

Answer 22

1.3 cm

Question 23

bronchi?

Answer 23

0.75 cm

Question 24

bronchiole diameter?

Answer 24

0.2 cm

Question 25

alveoli diameter?

Answer 25

0.05 - 0.03 cm

Question 26

What factors increase sedimentation?

Answer 26

large size, hi particle density, long time, small radius

Question 27

what factors decrease drug impaction?

Answer 27

small size, large radius, large angle, low velocity

Question 28

what is the best particle size for pulmonary delivery?

Answer 28

1-5 um

Question 29

Do most drugs do local or systemic delivery?

Answer 29

local

Question 30

What are the methods for pulmonary delivery?

Answer 30

aerosol, instillation/intra-tracheal

Question 31

What product is administered intra-tracheally?

Answer 31

Exosurf (infant surfactant)

Question 32

What are the advantages to a volatile liquid propellant aerosol?

Answer 32

pressure is constant if liquid propellant present = reproducibility

Question 33

How do droplets form in volatile liquid propellant aerosol?

Answer 33

hi-speed drug release

Question 34

How are drug particles cleared in pulmonary delivery?

Answer 34

1) mucociliary escalator (60% per hour), 2) macrophages