in relation to API related Nitrosamines we were facing the issue that the provided standard from an external source seems to be of poor quality.
Does any one have good experience with a company providing API related nitrosamine standards or maybe an recommendable contract lab able to produce API related standards?
Is there any option to perform a confirmatory testing without the respective standards in place?
Can you share more on the specific API related nitrosamine you are interested in? Feel free to also share what you need with USP’s new pharmaceutical analytical impurities program which was established recently to create quality reference materials for pharmaceutical impurities. Your inputs can help shape the pipeline of new impurities materials being developed. You can email PAI@usp.org.
If the impurity is a NDSRI and UV active, you may check the response factor against the respective API. Use impurity and API in equal concentration (say, 0.1 mg/mL) in suitable diluent and check the peaks response with LC-UV. If the impurity is pure, you would get the response factor close to ‘1’. Make sure to do the salt correction wherever applicable.