On-line gradient calibration for atomic absorption spectrometry

Abstract

A microprocessor-controlled, automated, on-line method for generating calibration standards is described. Mathematical gradients, programmed with a high-performance liquid chromatographic pump module, mix stock and diluent solutions to form desired concentrations. On-line produced gradient calibrations are demonstrated to be comparable to those made with individual solution standards. Advantages of the technique are the convenience and savings involved in maintaining a limited selection of stock solutions and the ease of performing standard additions calibrations. A possible drawback is a slight, but noticeable, time lag between successive gradient steps.