formulation of tablets

1. T
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Presented By- Ms. Prinsy Rana
Assistant Professor
MMCP, MM(DU)
Mullana, Ambala

2. CONTENTS
Introduction .
Formulation.
Design.
Manufacturing
.
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4. TABLETS
 Tablets are solid preparations
 Consisting of one or more active ingredient
Obtained by compressing uniform
volumes of particles into various sizeand
shape.
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5. THE ADVANTAGES OF THE TABLET
• They are unitdosage
• Greatest dose precision and the least content
variability.
• Cost is lowest of all oral dosage form.
• Lighter and compact.
• Easiest and cheapest to package.
• Easy to swallowing .
• Special release product is possible by entericcoating
or delayed release product.
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6. • odour and bitter tastecan bemaskedby coating
technique.
• Suitable for large scale production.
• Greatest chemical ,mechanical and microbial
stability over all oral dosageform.
• Product identification is easyand cheapest.
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7. DISADVANTAGESOFTABLET
• Difficult to swallow in case of children and unconscious
patients.
• Some drugs resist compression into densecompacts.
• Drugs with poor wetting, slow dissolution properties, is
difficult to formulate.
• Bitter drugs, with an objectionable odor that are
sensitive to oxygen may require encapsulation or
coating.
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8. DIFFERENTTYPESOFTABLETS
(A) Tablets ingested orally:
1.Compressed tablet. e.g. Paracetamol tablet
2. Delayed release tablet. e.g. Enteric coated Bisacodyl
3. Sugar coated tablet.
4. Film coated tablet.
5. Chewable tablet.
e.g Multivitamin tablet
e.g. Metronidazole tablet
e.g. Antacid tablet
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9. Tablets used in oral cavity
1. Buccal tablet e.g. Vitamin-c tablet
e.g. Vicks Menthol tablet
2. Sublingual tablet
3.Troches or lozenges
4. Dental cone
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10. (c) Tablets administered by other route:
1.Implantation tablet
2. Vaginal tablet, e.g. Clotrimazole tablet
(D) Tablets used to prepare solution:
1.Effervescent tablet, e.g. Dispirin tablet (Aspirin)
2. Dispensing tablet, e.g. Enzyme tablet (Digiplex)
3. Hypodermic tablet
4. Tablet triturates e.g. Enzyme tablet (Digiplex)
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11. TABLET GRANULATION
Granulation: Theprocessin which the primary powders
particles are madeadhere to form larger Multi particle entities
called granulation.
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12. 11
Powders intended for compression into tablets must possess
two essential properties.
Powderfluidity or flowability
• Powder flow can be improved mechanically by the use of
vibrators, glidant.
Powdercompressibility
• The property of forming a stable, intact compact mass
when pressure is applied is called powder
compressibility.
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13. ADVANTAGES OF GRANNULATION
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• To avoid powder segregation.
• To enhance the flow of powder.
• To produce uniform mixtures.
• To produce dust free formulations.
• To eliminate poor contentuniformity.
•To improve compaction characteristics
of mix.

14. Manufacturing of granules
Dry granulation method wet granulation method
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15. Dry granulation
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Compaction of
powder
milling
screening

16. 15
Advantages
Less
equipments
& space
Eliminate
need of
binder
solution
Disadvantages
No uniform
color
distribution
Process
create more
dust

17. Drug
Excipients
Diluents
Disintegrant
Large sized tablets
Slugs
Granules
Disintegrant
Glidant
Lubricant
tablets
Compression
granulation
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Weighing
Mixing [blender]
Slugging[tablet press,
roller compactor.
Screening sieve[20-25]
Mixing
Compression [tablet
press]

18. Roller compactor
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On a large scale compression
granulation can also be performed ona
roller compactor.
Granulation by dry compaction can also
be achieved by passing powders between
two rollers that compact the material at
pressure of up to 10tons per linearinch.

19. WETGRANULATION
It involves massing of amix of dry Primary powder
particles using aGranulatingfluid.
The fluid contain asolvent that must beVolatile and
non-toxic egwater, Ethanol.
Thegranulating solvent may contain aBinding agent
to ensure particle Adhesion after drying.
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20. 23

21. Advantages of wet granulation
prevent segregation of the constituents of
the powder blend.
Improved cohesivenessand
compressibility.
To improve homogeneity.
Uniform distribution of contentsand
colour .
The dissolution rate of hydrophobicdrugs
may beimproved by wet granulation
method.
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22. Limitationsofwet granulation:
• Multiple separate stepsare involved.
• Not suitable for heat and moisture sensitive drugs
• It is an expensive process-
• Cannot beusedfor moisture sensitive drugs.
• Theuseof soluble dyesoften lead to migration of
dyesduring drying stage.
granulation
Equipments
Traditionally, dry mixing in wet
process has been carried out using,
 Sigma blade mixer,
 Heavy-duty planetary mixer.
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23. Direct compression
SomeCrystalline substancescan compressdirectly.
Directly compressible diluent isan
Inert
Compactable
Maintain compression capacity evenafter adding disintegrates and
other ingredients.
Direct compression materials should posses
Good flow andcompressibility
Inert
Tasteless
Reworkable
Inexpensive
Able to disintegrate.
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24. 18
Important Steps
1. Milling of drugs andexcipients
2. Mixing of ingredients
3. Tablet compression

25. Mechanism of granule formation
Divided into 3
Nucleation
Transition
Ball growth
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26. GRANULATION EQUIPMENTS
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Single pot granulator.
High shear mixture granulator.
Fluid bed granulator.

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Single pot granulation
The granulation is done in a normal
high shear processor and dried in same
equipment.
e.g. Single Pot Processor /
One-Pot Processor

28. Single pot granulator
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29. Rapid mixer granulator
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30. High shear mixture granulation
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Dry Powder mixing (Approx 2-5 mins)
Liquid binder addition (Approx 1-2 mins)
Wet massing
Wet sieving of granules
Drying
Dry sieving of granules

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Short processing time.
Lesser amount of liquid
binders required .
Highly cohesive material
can be granulated.
Increase in
temperature may cause
chemical degradation
of thermolabile
material.
Over wetting of
gr
size lumps formation.
ADVANTAGES DISADVANTAGES

32. Fluid bed granulator
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Fluidization is the operation by which fine
solids are transformed into a fluid like state
through contact with a gas.
Granulating and drying can be completed in one
step inside the machine.

33. 35
-Homogeneous granules.
---Gentle product handling.
--Uniform spraying of all
particles in the fluid bed.

34. Advantages
Reducesdust formation during
processing
reduces product loss.
Improves worker safety.
processsuitable to:
Potent compounds
Minimizing product/operator
Exposure
Minimizing crosscontamination.
Reducedprocess time
Reducedequipment and floor
space requirements.
DISADVANTAGES
The Fluid Bedcleaning i
s
labor-intensive and time
consuming.
Difficulty ofassuring
reproducibility.
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35. TabletsExcipients
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36. The common
types of tablet’s
excipients are
described in the
figure.
38
Diluents
Binders $
adhesives
Disintegrants
Colours,
sweeteners
$flavors

37. Diluent or filler
Bulking agent.
Increase sizeof the tablet.
Suitable for handling.
Most common fillers intablets:
1. Lactose.
2.Sugar or sugar alcohol (glucose,sucrose,sorbitol and
mannitol).
3. Cellulose and microcrystalline cellulose.
4. diCalcium phosphate dihydrate.
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38. Requirements for a good diluent
Chemically inert, biocompatible, cheap.
Non-hygroscopic.
Good biopharmaceutical properties.
water soluble or hydrophilic.
compatibility
Havean acceptable taste.
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39. Disintegrants
Toensure that the tablet, when in contact with a
liquid,
breaksupinto small fragments,
which promotes rapid drugdissolution.
41

40. Stepsofthedisintegrationprocess
First: The liquid wets the solid
and penetrates the pores of the
tablet.
tablet breaks into smaller
fragments
(aggregates of primary
particles).
Second:Theaggregates will
deaggregateinto their primary
powder particles.
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41. TheMethodofDisintegrant Addition
Mixed with other ingredients prior to granulation &
thus incorporated within the granules
(INTRAGRANULARADDITION).
Mixed with the dry granules.(EXTRAGRANULAR
ADDITION).
Incorporated asbothan intragranular and an extra
granular portion.
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42. CommonlyUsedDisintegrants
1. Starch.
2.Cellulose (e.g.sodium carboxymethyl cellulose).
Typicalconcentrationof1-5% byweight
3. High swellingdisintegrants
(Modified Starch or Modified cellulose, in concentration
of 1-2%
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43. Binder
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Ensure that granules and tablets can beformed with
the required mechanical strength ( glue that holds
powders together to form granules).
Eg- starch paste
Glucose
Gelatin solution
Acacia
Sucrose

44. Incorporationof binder
1. Dry Powder
Asdry powder mixed with other ingredient before wet
granulation
Asadry powder in dry granulation (roller compaction,
slugging)
2. Solutionbinder
As asolution in wet granulation.
Binder can beadded either dry with other excipients for
granulation or
Already dissolved in the granulating fluid;
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45. Typical binderconcentrationis2 – 10%b
y
weight
Binderscan be:
Insoluble in water, e.g.starch
Soluble in water e.g.HPMC
Soluble in water and ethanole.g.Povidone
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46. LUBRICANT
Lubricants prevent adherence of
granule/powder to die wall and to
promote smooth ejection from the die
after compaction.
Mechanisms of Action :
1. Fluidlubrication.
2. Boundarylubrication.
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47. 1. Fluidlubrication
Alayer offluid islocatedbetweenthemovingsurfaces
separating them from eachother & thus reduces the friction,
e.g.liquid paraffin.
2. Boundarylubrication:
The sliding surfaces are separated by only avery thin film of
lubricant.
So, the nature of the solid surfaces will therefore affect
friction.
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48. Disadvantagesof lubricants
1. Lubricants tend tobehydrophobic.
Under-lubricated blends tend to flow poorly and show
compression sticking problems
Over-lubricated blends can adversely affect tablet hardness
and dissolution rate, aswell astabletstrength.
Eg:
Magnesium Stearate
Calcium Stearate, Talc
StearicAcid
Sodium Lauryl Sulfate, liquid Paraffin, propylene glycol, (PG)
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49. Glidant or flow aid
Improve flowability of thepowder
added during direct compaction and togranulation
before tableting ( theyreducinginterparticulate
friction).
CommonGlidants are
1. Talc ( at concentration 1-2 %).
2. Colloidal silica ( 0.2%
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50. Antiadherent
Reduceadhesion between the powder and the
punch faces& thus prevent particles sticking to
the punches; due to excessmoisture or
engraved and/or embossedpunch face.
Many lubricants, such asmagnesium stearate,
have also antiadherent properties.
Also talc and starch can act asantiadherents.
52

51. S
orbent
Are substancesthat are capable of
sorbing somequantities of fluids in an
apparently dry state.
Thus, oilsor oil-drug solutionscan be
incorporated into apowder mixture
which is granulated & compactedinto
tablets.
e.g. Microcrystalline cellulose& silica.
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52. Flavor
Give the tablet amore pleasant tasteorto
maskan unpleasant one.
Flavoring agentsare often thermolabile and
socannot beadded prior to an operation
involving heat.
They are often mixed with the granulesa
s
an alcohol solution.
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53. Colourent
It is added to tablets to aid identification and
patient compliance.
added during coating.
It can also be added prior to compaction. ( can
beaddedasan insoluble powder or dissolvedin
thegranulationliquid. )
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54. S
weeteners
They are usedin chewabletabletto exclude
or limit the useof sugar in thetablets.
Mannitol, 72% assweetassucrose.
Saccharin,500 times sweeter than sucrose.
Disadvantage
hasabitter tasteafter sometime and
carcinogenic.
Aspartame, Largely replace saccharin.
Disadv.: Lack of stability in the presenceof
moisture.
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55. Tablet compression
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56. TabletCompressionMachine
Hopper for holding and feeding granulesor
powder to becompressed.
Diesthat define the size and shapeof the tablet.
Punchesfor compressing the granules within
the dies.
Afeedingmechanismfor moving granules
from the hopper into thedies.
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57. Tablet
machine or
tablet press
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58. The compression cycle for a single
punch tablet machine
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59. StagesofTabletFormation
(CompactionCycle)
Gravitational flow of the powder from hopper via the dietable
into the die .
(the die is closed at its lower end by the lower punch).
Tablet formation
The upper punch descends,enters the die ,the powder is
Compresseduntil atablet is formed.
After maximum applied force is reached,the upper punch
leavesthe powder.
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60. Tabletejection
The lower punchrisesuntil its tip reaches
the level of the top of the die.
The tablet is subsequently removedfrom the
die and die table by apushing device.
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61. 63 Tablet presses
Single punch.
Rotary press.
High speedrotary press.
Multi layer rotarypress.

62. SinglePunchpress(EccentricPress):
Bench-top models that make one
tablet
At atime (single-station presses)
Disadvantages: production of small
batchesof tablets
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63. Rotary Press( Multi station Press):
(10 000 tabletsperminute)
Large scaleproduction.
It consists of anumber of diesand setsof punches(
from 3 up to60).
The diesare mounted in acirclein the dietable
both the die and the punches rotate together during
operation of the machine.
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65. 67
The powder is held in ahopperwhose lower
opening is located just abovethe die table.
Thepowder flows on to the dietable& fed into the
dieby afeed frame.
During powder compression both punchesoperate
by vertical movement.
After tablet ejection,the tablet is knocked away a
s
the diepassesthe feedframe.

66. Reference
Text book of physical pharmacy by Tripathi pg no 210-263.
Sherwood BE& BeckerJW(1998) “Anew classof high-
functionality excipients: silici-fied microcrystalline cellulose”
Pharm Tech22 78–88.
Vogel, P
.J.;Schmidt, P
.C.Force–Time Curves of aModern
Rotary Tablet Machine. II. Influence ofCompression Forceand
Tableting Speedon the Deformation Mechanisms of
Pharmaceutical Substances.Drug Dev. Ind. Pharm. 1993, 19,
1917.
The theory and practice of industrial pharmacy fourth edition
by lachman/lieberman pageno 449-543
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