The limits of detection (LOD) and quantification (LOQ) are evaluated using the following equations _{[1-4]}:

LOD=3.3 S_{0}/b

LOQ=10 S_{0}/b

*where S _{0} is the standard deviation of the calibration line’s y-intercept
where b is the slope of the linear regression line of best fit.*

The limit should be subsequently validated by the analysis of a suitable number of samples known to be near or prepared at the quantitation limit.

*References:*

*[1] Ermer, J.; Validation in pharmaceutical analysis. Part I: an integrated approach; Journal of Pharmaceutical and Biomedical Analysis, (2001); 24: 755-767.*

*[2] Perez-Bendito, D., Silva, M.; Kinetic Meth. in Analytical Chemisry; Chichester, Ellis Horwood, (1988), pp. 254.*

*[3] Mottola, H.A.; Kinetic Aspects of Analytical Chemisry; New York, Wiley, (1988), pp. 40.*

*[4] Thomsen, V., Schatzlein, D., Mercuro, D.; Limits of detection in spectroscopy; Spectroscopy, (2003); 18(12): 112-114.*

*[5] Dolan, J.W.; What’s the Problem with the LLOQ? — A Case Study, LC-GC North America, 31 (11), pp. 926-931.*