tabletting 2

Question 1

what is powder compressibility?

Answer 1

‘it’s propensity, when held within a confined space, to reduce in volume when subjected to a load”

Question 2

what is plastic deformation?

Answer 2

when particles stay deformed and cohesion is kept

Question 3

what is elastic deformation?

Answer 3

cohesion is lost and particles return to original shape

Question 4

how is compression is plastic material?

Answer 4

particles flow and voids are filled so more contact area for bonding

Question 5

compression of elastic materials?

Answer 5

the particles deform once pressure is applied but store the energy. they then release the energy, causing the tablet to expand, providing a stress form within which weakens the tablet

Question 6

examples of elastic materials?

Answer 6

disintegrants

Question 7

compression of brittle materials?

Answer 7

particles shatter, the voids are filled and increases contact area for bonding

Question 8

what is viscosity a combo of?

Answer 8

elastic and plastic behaviour

Question 9

what are the types of bonds formed during tabletting?

Answer 9

‘mechanical interlocking, melting at contact points, molecular bonding where surfaces meet’

Question 10

what two things can be adjusted on a tabletting machine?

Answer 10

dwell time, maximum pressure

Question 11

what is the linear region?

Answer 11

hardness depends on pressure applied and pressure can be adjusted

Question 12

what is lamination?

Answer 12

horizontal layers ad cracks forming because of over compression

Question 13

what is the A region?

Answer 13

the loose compacted region
little bonding of particles
no strength
called the powder plug used to fill in capsules

Question 14

what is the B region of tabletting machine?

Answer 14

linear region
inter-particulate bonding
more pressure so more tablet strength
air in the voids of the tablet

Question 15

what is the C region of tabletting machine?

Answer 15

maximum compaction
maximum bonding of particles
maximum bonding
maximum air in voids

Question 16

what is the D region of tabletting machine?

Answer 16

excess compression
bonds break because extra energy no longer used to make more bonds
lamination occurs which reduces the strength of the tablet

Question 17

why do plastic materials need more dwell time?

Answer 17

because they flow with time so more internal bonds can be made therefore stronger tablets

Question 18

what is capping?

Answer 18

the top of the tablet comes off because of lamination

Question 19

what is chipping/sticking?

Answer 19

chipped sides of the tablet and holes in tablet form sticking to the punch

Question 20

what are stress cracks in tablets?

Answer 20

cracks caused by too much elastic expansion

Question 21

what is friability?

Answer 21

during transportation:
the edges erode
powder is shedded

Question 22

problems in formulations?

Answer 22

too much elastic ingredient
too much compressible drug
drugs that have a low melting point
drugs that react with excipients
wrong quantity of lubricant or mixed for a wrong time period

Question 23

consequences of too much elastic ingredient?

Answer 23

‘stress cracks and friable’

Question 24

consequences of too much compressible drugs?

Answer 24

lamination or capping or friability occurs

Question 25

consequences of drugs with low melting points?

Answer 25

sticks to punches and melts during tabletting because of the heat

Question 26

consequences of drugs reacting with excipients?

Answer 26

doesn't happen often because discovered in pre-formulating studies

Question 27

consequences of lubrincants?

Answer 27

not enough lubrication leads to struggle of ejection of tablet too much lubricant leads to fewer inter-particulate bonds so weaker tablets therefore more friable

Question 28

what are the types of tablet machines?

Answer 28

single punch, rotary, compaction simulator

Question 29

what are the properties of single punch?

Answer 29

50 tablets per minute rarely used

Question 30

what are the properties of rotary machines?

Answer 30

multiple punches 20,000 tablets made per minute small machines used for lab and pilot scale big ones used for full scale manufacturing

Question 31

what are the properties of compaction simulator?

Answer 31

single punch one tablet at a time lots of sensors

Question 32

advantages of compaction simulator?

Answer 32

'needs few grams of drug since it makes one tablet so useful in early development when new drug is in short supply'

Question 33

disadvantages of compaction simulator

Answer 33

very expensive

Question 34

options of coating tablets?

Answer 34

slide 17 tablets and tabletting part 2 ppt

Question 35

how is a tablet sugar coated?

Answer 35

coating liquid poured onto the bed of the tablet rotation coats the tablets evenly coat is left to dry before next coating

Question 36

what are the variables of sugar coating tablets?

Answer 36

rotation speed air flow air temperature rate of pouring in the liquid

Question 37

what is the process of polymer film coating?

Answer 37

coating liquid sprayed into tablet bed drum rotated to spread coating on the surface evaporation of liquid to form solid polymer firm

Question 38

variables of polymer film coating?

Answer 38

spray rate drum rotation speed temperature air flow

Question 39

what does the liquid for film coating contain?

Answer 39

polymer latex plasticiser colour surfactant separating agent

Question 40

what is the polymer latex for?

Answer 40

no organic solvent

Question 41

what is plasticiser for?

Answer 41

help polymer particles coalesce

Question 42

what is colour for?

Answer 42

'as a fine suspension lake'

Question 43

what is the surfactant for?

Answer 43

'to help liquid spread quickly'

Question 44

what is the separating agent for?

Answer 44

so tablets don't stick together during drying

Question 45

how does a film coat form?

Answer 45

'latex suspension sprayed onto the tablet, liquid evaporates, latex particles coalesce to form a polymer film'

Question 46

how does compression coating and multilayer coating happen?

Answer 46

'powder compressed into weak tablet coating formulation compressed onto it double compression forms strong tablet'

Question 47

properties of compression coating and multilayer coating

Answer 47

special tabletting machine required