Hard & Soft Capsules Flashcards
What is the materials used to make soft capsules?
- Gelatin
- Thermoplastic potato starch
How are capsules orally administered?
Swallowed - drug in caps filling
Bitten - drug absorption
Sucked - drug in thick, soft - gelatine shell
What are the advantages of soft caps compared to tablets?
- No compression - high dose of poorly compressible drug is difficult to form tablets.
- Optimum content uniformity - decrease dose variation in soft caps.
- Increase in shelf life for oxidation prone drugs
What is the composition of soft caps?
Gelatine - colorants, water, plasticizer, film coating, higher elasticity - defined viscosity
Thermoplastic potato stratch - plasticizer, anti-caking agent, water and protective coat
Explain the bioavailability of soft caps
Depends on choice of filling
- drugs soluble in acidity -water miscible filling and drug suspended.
- drugs insoluble in acidity - drug dissolved in filling
What is the manufacturing process for soft caps?
- The globex method
- Rotary die alternative method
Describe the globex method.
- Lipophilic shell and formulation stored in separate containers.
- Fill and shell materials pumped through double capillary.
- Pulsing action gives predetermined fill volume, separating dose units.
- High surface tension gives to droplets
- Capsules fall through immiscible cooling bath
- Caps are collected, washed and dried.
What are the filling for soft caps?
- Suspensions
- Pastes
- Only liquids
- Liquids miscible with water
- Solid/ semi-solid material
What are the advantages of soft caps filling?
- Increased bioavailability of poorly soluble drugs.
- Prevention of partial dissolution and re-crystallisation of drugs
- Masking bad taste/ odour
- Safe and simple manufacture
What are the disadvantages of soft cap fillings?
- Emulsions are unstable due to water loss so they crack.
- Surfactant affect caps sealing
- Drugs/ excipients containing water that dissolve gelatine/ starch changes their properties
- pH limits
What material is use for hard gelatin caps (HDCs)?
Fibrous protein, made from collagen - animal skin, bones, hide, tendons
- H bonding/ weak covalent bonds
What is the process of obtaining fibrous protein?
- Size reduction, removal of meat, blood, fat
- Hydrolysis, denaturation of quaternary structure - reduce strength
- Extraction, washing and sterlilzation
- Drying, size reduction and fractionation
What are the positives of Fibrous protein for HGC?
- Soluble in acid environment of stomach
- Solution gives suitable viscosity with thermally reversible gelation properties.
- Films are clear, strong, flexible and high loss
Why is gelatin/PEG used in HGC?
lower moisture
less sensitive to hygroscopic materials
Why is HPMC used in HGC?
low moisture content
no light degredation or cross linking
soluble at room temp - gelatin isnt
