Product Testing Stability Flashcards
(13 cards)
Routes of degradation
Oxidation
Photodegradation
Heat
Solvents degradation
Acid and base catalysis
What to do if drug can hydrolysis in water
Replace water with another solvent
How can you store unstable drugs
Penicillin
Store as free dried powders and then reconstitute before use
How to protect from uv light
Use a tinted glass container or opaque outer container like cardboard
To protect from oxygen
Flush with inert gas (N2)
To prevent oxidation
Add a chelating agent (EDTA) to bind to metal and prevent catalytic activity
Also add an antioxidant (removes oxygen)
Disadvantages of liquid dosage forms
Shedding of particles from glass container
Loss of drug to container
Extraction of material from container into liquid= possible toxicity or change in ph
Evaporation of volatile components = poor taste
Stability testing
Hydrolysis = heat in acid/ basic conditions
Oxidation= with/without oxygen flushing
Light= with/ without exposure to artificial daylight lamps
Stress testing
Store drug at elevated temperatures to accelerate aging and use Arrhenius eq to back calculate rate of degradation
Advantages to stress testing
Speeds up the degradation process
Disadvantage to stress testing
Prediction of degradation rates not always accurate as different reactions may occur at elevated temp
Dissolved oxygen concentration decline on heating and so does moisture levels
Why is it important to study product stability in all the zones where the product will be sold?
Differs in temp and humidity
Important to study product stability is all the zones the product will be sold
What features of a pharmaceutical suspension/ emulsion would we investigate during long-term stability testing?
precipitate formation
pH
viscosity
whether there were any extractables in the continuous phase
the level of microbial contamination, dispersibility
rheological properties
size and size distribution of particles,
and finally see if there had been any polymorphic conversion
