How to calculate LOD/LOQ using calibration curve with ISTD

[s2008]

Hello Guys:
I checked the literature about using calibration curve to calculate the LOD/LOQ. However, all the example using response (y variance) and concentration ( X variance) is absolute response or concentration. they are never normalized by concentration or response from internal standard. So I have the following questions?

(1) how to calculate the LOD/LOQ using calibration curve with internal standard are used?

(2) In this case, we only use response (y variance) and concentration ( X variance) is absolute response or concentration without any internal correction?

Thanks advance

[rb6banjo]

Did you search this forum? There have been a number of threads on this topic since I joined the forum. Search "limit detection quantitation" (or something to that affect) and see what you get. I bet you can find the answer to your question in a previous thread.