Basic Training 4th Annual ICP Conference

17.24 Method Validation

Confirm Basic Performance Criteria : Limit of Detec4on (LOD)

• Limit of Detection (LOD) is a criterion that can be difficult to establish. • The detection limit of the method is defined as 3*SD0, where SD0 is the value of the standard deviation as the concentration of the analyte approaches 0. • The value of SD0 can be obtained by extrapolation from a plot of standard deviation (y axis) versus concentration (x axis) where three concentrations are analyzed ~ 11 times each that are at the low, mid, and high regions of interest. • This determination should be made using a matrix that matches the sample matrix.

17.25 Method Validation

Confirm Basic Performance Criteria : Sensitivity

• Sensi&vity or delta C = 2 (2)1/2 SDc , where SDc is the standard devia&on at the mid point of the region of interest. • This represents the minimum difference in two samples of concentra&on C that can be dis&nguished at the 95% confidence level.