Analytical Chemistry Lesson of the Day – Linearity in Method Validation
August 5, 2015 Leave a comment
In analytical chemistry, the quantity of interest is often estimated from a calibration line. A technique or instrument generates the analytical response for the quantity of interest, so a calibration line is constructed from generating multiple responses from multiple standard samples of known quantities. Linearity refers to how well a plot of the analytical response versus the quantity of interest follows a straight line. If this relationship holds, then an analytical response can be generated from a sample containing an unknown quantity, and the calibration line can be used to estimate the unknown quantity with a confidence interval.
Note that this concept of “linear” is different from the “linear” in “linear regression” in statistics.