What is a calibration curve?

A calibration curve is a graphical representation of the relationship between the concentration of a substance in a sample and the response of a measurement instrument, typically a spectrophotometer or chromatograph. This curve is created by measuring the response of the instrument at different known concentrations of the target substance.

Calibration curves are used in analytical chemistry to quantify the amount of a specific analyte in a sample by comparing the measured response of the instrument to the response of known standard solutions of the analyte. By plotting the response against the concentration of the standard solutions, a calibration curve can be generated, which can then be used to determine the concentration of the analyte in unknown samples.

Calibration curves are important in ensuring the accuracy and reliability of analytical measurements, as they account for any variations in instrument response due to factors such as drift, noise, or matrix effects. They also provide a way to validate the performance of the instrument and the method used for analysis.