tabletting lecture 1 Flashcards
why are tablets used so much?
small
portable
stable
can be marketed well
palatable
how are tablets stable?
no water and the coating blocks the light
how is tablets good for marketing?
can be assigned a shape and colour to a market identity to match the company
how are tablets palatable?
the taste of the drug can be masked
how is packaging for tablets easy?
can be made to resist water, light to avoid damage
what is basing?
dry mixing in lubricant
what is the manufacturing process of tablets?
slide 13 of
Tablets and Tabletting part 1 ppt
what are the different scales?
laboratory, pilot, full scale industrial
what is made during the laboratory scale?
formulation design stage
what is made during the pilot scale?
clinical trial testing stage
what is made during the full scale industrial scale?
the commercial product
what behaviours of raw materials are important to control?
powder flow, wetting, compression
when does movement of powders occur?
tablet machine vibration, mixing and pouring to make the tablet, transport
what are the consequences of smaller particles dropping to the bottom?
varying drug dose
an increase or decrease in amount of excipient in the medicine
why do we granulate?
to stop different particles form seperating
how does wet granulation occur?
water-soluble polymer used to stick particles together
spray granulator used to spray a layer of water soluble polymer over the granules
how does dry granulation occur?
through compression
why is high speed mixers used over traditional mixers?
all mixed in the same place in stainless steel bowl so less transfer so less material loss
process of wet granulation?
dry powders added to bowl and mixed, then granulating liquid added and mixed by impeller then chopper turned on to separate granules then discharged via port through wire mesh to break up larger bits
then granules placed in fluidised bed dryer
how do fluidised bed granulators work?
heated air sucked through powder to mix, powder sprayed with granulating fluid then dried with heated air
how does dry granulation occur?
made into granules without using pressure, no heat variation, then machine compacts them into flakes and a second machine breaks them into granules.
a compressed sheet is formed by two rollers
ribbon is then sieved into granules
what is direct compression?
there no granule formation so less expensive
advantages in direct compression?
no granulation, no wetting and drying, faster product development time, saves money
disadvantages of direct compression?
only for powders that don’t segregate
the powder must flow
specialised excipients required
what is the tablet compression cycle?
die filled with powder
upper punch lowers and forms tablet
upper punch lifts up
lower punch ejects tablet
what are the required properties of tablets?
good flow, compactable powder mix, powder mix that resists separation, a powder mix that has the right amount of lubrication
