Beam-injection flame-furnace atomic-absorption spectrometry (BIFF-AAS) with low-pressure sample-jet generation

摘要

Flame-furnace AAS (FF-AAS) comprises two individual, recently developed FAAS techniques remarkable for their high power of detection and the small amounts of sample required. One the these techniques is beam-injection flame-furnace AAS (BIFF-AAS), where-by the sample is introduced into a flame-heated atomization cell as a high-speed liquid jet. For the first time this sample-introduction beam has been generated at low pressure by use of a peristaltic pump and a special micro channel smooth jet nozzle developed for this application. Compared with standard FAAS a 7- to 17-fold improvement in the power of detection was obtained for six elements (Ag, Cd, Hg, Pb, Se, and Zn). The relative standard deviation (N=15) was between 0.75 and 3.45. Sample volumes between 10 μL and 1 mL have been investigated. The applicability of the peristaltic pump for beam generation enables an optimum sampling mode for a variety of analytical tasks (continuous samples uptake, manual or automated, or different flow-injection modes). The method can also be regarded as a simple, effective interface between FIA techniques and flame AAS.