Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: Bliss on August 03, 2010, 12:13:42 AM
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Hiya,
1.1. Heat (80ºC) – the samples were kept in sealed containers in an oven at 80ºC. Samples were taken out after seven days and samples were analysed as per method
1.2. Heat and humidity (40ºC/75% RH) – the samples were kept in open containers in an oven at 40 ºC and 75% RH for seven days.
1.3. Oxidation – 10 mL of 30% H2O2 was added to the samples and allowed to stand for 24 hours prior to extraction and final dilution.
1.4. Acid degradation – 10mL of 0.1 N HCL was added to the sample and heated for 4 hours at 55 ºC. The solution was neutralized afterwards prior to extraction and final dilution.
1.5. Based degradation – 10 mL of 0.1 N NaOH was added to the sample and heated for 4 hours at 55 ºC. The solution was neutralized afterwards prior to extraction and final dilution.
I have been told of the above instruction regarding stability study for my nanoparticles that I have formulated. Unfortunately, there are no references provided for them. Do they look familiar to anyone?
If you can't recognise it, could you please provide me with another reference that explains how to do the stability testing? I've looked through ICH, but the instructions were not clear enough. Thank you :)
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These are standard tests used in the pharmaceutical industry to investigate the potential instability of drug substances (the active pharmaceutical ingredient-API) or drug products (the API formulated with the appropriate excipients). They are performed to give information regarding potential shelf-life/ formation of toxic compounds etc. in a relatively short-time frame.
The stressed samples are analyzed (virtually always by HPLC/UV) to determine how many degradation products are formed, and at what levels.
You might typically prepare samples at 1 mg/mL for HPLC analysis. Search the literature to discover any known degradation products of your nanoparticles; failing that, draw the chemical structures and then try to predict the action of acid/base/oxidative stress etc.
Another important stress test is with UV and full-spectrum light.
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Yup, but the main problem that I am facing is the lack of guidelines that specify the exact numbers (e.g. 60 degree celcius) to follow
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Have you looked here http://www.ich.org/cache/compo/276-254-1.html (http://www.ich.org/cache/compo/276-254-1.html)