N-Nitroso Desethyl Amiodarone için metot geliştirme çalışması yapmaya çalışıyorum. Limiti çok düşük olduğu için numuneye spike yaptığımı geri kazanım alamıyorum. Birçok kolon, mobil faz ve solvent denedim. Aynı sorunu yaşayan ya da öneride bulunabilecek kimse var mı?
When you say the limit is low, does that mean you are working with a relatively high sample concentration?
If so, matrix effects are very likely your main issue. What does your sample preparation look like? It sounds like the API or finished product is simply dissolved in solvent without any cleanup.
Which columns have you tried so far?
Do you have a UV detector installed, or at least a way to monitor the API retention time?
If the API and the impurity elute at the same time (or very close), you will inevitably run into problems.
You could try to improve the separation by optimizing the gradient and/or changing the column chemistry, but with so little information provided it is difficult to give specific advice.
Another option is MS optimization. If your MS sensitivity can be improved by, say, one order of magnitude, you could dilute the sample tenfold, which often helps significantly with matrix effects.
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Hello, may I ask what type of sample you have? Is it an active pharmaceutical ingredient or a finished formulation? Is it an injectable solution?