Hi, here you can find more than method for LOD & LOQ calculation

https://rd.springer.com/article/10.1007/s42452-019-0825-5

There is another reference for calculation of LOD and LOQ

https://rd.springer.com/article/10.1007/s42452-019-0237-6

Yes, to calculate LOD & LOQ using the standard deviation of the response and slope criteria you should use the residual standard deviation (σ) of regression line not the SD. And you can easily get it by using the standard error (STEYX) function of regression line in Excel.

Hope this helps.

Prashant Chaturvedi; kindly send me your email to get Excel sheet for LOD & LOQ calculation and you can calculate it as the following:

These approaches are based on the standard deviation of the response and the slope. A specific calibration curve should be studied using samples containing an analyte in the range of LODand LOQ. The residual standard deviation of a regression line or the standard deviation of y-intercepts of regression lines may be used as the standard deviation. LOD=3.3×σ /slope and LOQ=10×σ /slope, where σ = the standard deviationof the response

Mostafa Farouk Al-Hakkani Thank you for the informative link. Nidal Batrawi i tried to calculate residual standard deviation with Excel and it is really easy to do. Thank you.

Mahmoud Abdelfatah please send the Excel sheet on [email protected]

Prashant Chaturvedi you're welcome.

you are welcome Prashant Chaturvedi