Application of differential technique is based on the comparison of the signal response of the standard with a sample of similar but unknown concentration on same sample-weight basis. Under the conditions for the use of the differential technique, in which the instrumental signal response of the unknown concentration in the sample cuvette is matched with that of the standard of accurately known concentration using a suitable reagent, which amount to a titration. In this way, accuracy and precision of the application of the differential technique in laser-induced fluorimetry/pulsed LEDfluorimetry were found to be comparable with differential spectrophotometric technique as well as to classical titrimetric and gravimetric methods. By analogy of differential technique with titrimetry, thus give rise to an absolute methodology based on the use of at least three independent analytical chemical standards or certified reference materials. Application of differential technique may prove valuable absolute methods in other fields of applications of fluorimetry and other sensitive techniques.
Published Date: 2024-03-01; Received Date: 2024-01-29
