Formulation of Advanced or Complex Medicines 10 SODF Flashcards
Give three examples of Solid Oral Dosage Forms
Tablets
Capsules
- hard
- soft
What are the important features of solid oral dosage forms?
Contain the correct quantity of active ingredients
- consistent dosing
Release the contents for absorption as designed
- once in solution during GI transit time
Stable for the life of the product
- sit on a shelf for a long time
Dispensed pack of medicines easily portable
- ambient storage conditions
Can be taken anywhere
- no special equipment
Size suitable for swallowing
- if can’t be swallowed, the contents won’t be released
Strong enough to be handled without damage
Appearance to give patient confidence
- colour change may worry patients
What excipients are likely to be in a capsule?
Pregelatinized starch
Dimethicone 350
Capsule shell contains
- gelatine
- colouring agents
- patent blue V
- titanium dioxide
- yellow ferric oxide
What does the manufacture of most tablets and capsules involve?
The use of particulate solids (powders)
How are powders for tablets and capsules measured for dosing?
By volume rather than weight
- easier to measure
What important properties of powders are there which need to be taken into consideration which would affect the design and success of the manufacturing process?
Bulk powder properties
- volume
- density
- porosity
Mixing
Particle shape/size
What are powders mixtures of?
Solid particles and air
Where is air present in a powder?
Between particles
In open pores on particle surfaces
Inside closed pores in particles
How can volume be interpreted?
Volume
- poured
- tapped
- compressed
Density
Porosity
What is the difference between poured and tapped volumes of powder?
Poured
- cubical packing
- 48% porosity
Tapped
- rhombohedral packing
- 26% porosity
Air displaced by tapping so particles more tightly packed
What is the equation relating porosity and bulk density?
Pb = m/V
Pb = bulk density
m = mass
V = volume
What is the definition of mixing powders?
Unit operation which aims to treat two or more components so that each particle lies as nearly as possible in contact with a particle of each other other components
If achieved
- perfect mix
How can you check if a mixture is mixed?
Take samples and determine composition by HPLC
What do the results of mixing samples depend on?
Sample size
Composition of mixture
Degree of mixing
- mixer type and efficiency
- mixing time
What are the three mechanisms of mixing powders?
Convective
Shear
Diffusive
