How do you choose the internal standards for analysis of organic compound classes with GC/MS technique?

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Sarika Gupta

yes Kenneth you are right....

Melanie Braun

Hello Sarika!

It s important that the internal standard has similar properties than the substances you want to analyze. When you are analyzing different substances, it might be bether to use different internal standards, too. And take care that the internal standards cover the range of mass you are analyzing. For e.g. PAHs there is an internal standard mix available (Sigma Aldrich), covering low to high mass......

Hope I could help you, best regards