STUDY OF THE BEHAVIOR OF THE ABSORBENT BLANKS IN ANALYTICAL PROCEDURES BY USING THE H-POINT STANDARD ADDITIONS METHOD (HPSAM)

This paper studies the behaviour of reagent blank in different extractive-colorimetric procedures (determination of sympathomimetic amines with NQS reagent) by using the H-Point Standard Additions Method (HPSAM) in order to study and characterize the different possibilities that the blank can introduce in an analytical procedure. We define two kinds of blanks: the external blank (from reagent alone solutions data) and the internal blank (from extrapolation of reagent plus analyte solutions data). Comparison between both gives the information about the reproducibility of the behaviour of the reagent blank. A procedure to evaluate, and characterize, errors (if they exist) is described, and a guide for optimizing the measuring procedure is presented.