L15 - Tablet Formation - Manufacturing

Question 1

What are the steps for the manifacturing

Answer 1

• mixing drug and excipients
• either
  
  • direct compression
  • wet granulation
  • dry granulation
  • fluidised bed granulation
  • granulation by spray drying
• lubricant mixing
• tablet formation

Question 2

What does ‘power’ mean in pharmaceutics?

Answer 2

• as a dosage form
  
  • ‘describes a formulation in which a drug powder has been mixed with other powdered excipients to produce a final product’
    
    • Aulton, 2002
• As a precursor of a dosage form
  
  • can be a precuroser of tablet either
    
    • directly - powder compressed to form a tablet
    • indirectly - via granules

Question 3

What is mean by granules in pharmaceutics

Answer 3

• as a dosage form
  
  • ‘granules as dosage forms are powder particles that have been aggregated to form larger particles 2 to 4 mm in diameter’
    
    • Aulton, 2002
• as a precursor of a dosage form
  
  • granules can also be an intermediate of tablet manufacturing
  • uslally 0.2 to 0.5mm

Question 4

what are the advtantages of using powders and granules as dosage forms compared to tablets/capsules/liquid

Answer 4

• more stable than a lquid
• conveneitn from large doses
  
  • 1 to 5g
• dissolution rate higher than capsule or tablet

Question 5

what are the disadvantages of using a powder and granules dosage form compared to tablets/capsules/liquid

Answer 5

• less convenient to carry than tablets/capsules
• difficult to mask unpleasant taste
• not suitable for adminisation of potent drugs
  
  • as dosage could more easily be mistaken
• not suitable for drug inactivated in the stomach or that can cause stomach damage/irritation
  
  • lack protective coating

Question 6

How are powders and granules used orally for pharmaceutical use

Answer 6

• bulk powder or granules for internal use
  
  • e.g. effervescent
• divided powder or granules
  
  • placed on small piece of paper

Question 7

What are the other adminitration routes for powders

Answer 7

• dusting powders for external use
• unsufflation (ear/nose/throat)
• antibiotic syrups to be reconsititued before use
• powders for reconstitution into injection
• dry powders inhalers

Question 8

what is granulation

Answer 8

• granulation is the process in which homogenous mixtures of primary powder particles form larger, still homogenous particles called granules

Question 9

what are the advantages of granulation

Answer 9

• improve powder flow
• prevent segragation
  
  • see image
• improved compaction
• oter reasons
  
  • reduces generation of dust - important for toxic compound
  • retain flowability after absorbing some moisture, whilst hygroscopic powder form cakes
  • occupy less volume - convenient

Question 10

what is wet granulation

Answer 10

• powders are mixed with a granulating fluid
• the mass is forced through a sieve
• then lubricant added and a tablet is formed

Question 11

What is the process of dry granulation

Answer 11

• pressure applid to mix
• the intermediate product is broken
• then passed through sieve
• lubricant added
• compressed to form tablet

Question 12

What is the mechanism of wet granulation

Answer 12

• adhesion and cohesion forces in immobile films
  
  • interparticulate distance decreases
  • increase in contact areas
• interfacial forces in mobile liquid films
• solid bridges (heardening binds or crystallisation of dissolved substances)
• attractive forces between particles

Question 13

what are the different granules formed and the different steps

Answer 13

Question 14

what is the mechanism for dry graniulation

Answer 14

• attractive force sbetween solid paricles
• solid bridges by partial melting
• mechanisms of granule formation
  
  • applied pressure
  • fromation o a sheet
  • milling and sieving
  • granules