In our last blog post we had a look on the first approach to infer accuracy from linearity in method validations by applying normalization. This can be used to determine accuracy in case no alternative methods or impurities for spiking are available. Apart from normalization, another possibility to solve this problem exists, which will be highlighted today.
We stick to our example of the last time: a SE-HPLC method is used for purity determination. The impurities are given as the sum of minor peaks, while the main peak is our desired product. The approach to infer accuracy from linearity is allowed by the ICH Q2(1) validation guideline, when specificity (we suppose this again) and precision is given.