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

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 of these techniques is beam-injection flame-furnace AAS (BIFF-AAS), whereby 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 0.7% and 3.4%. Sample volumes between 10 microL 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 sample 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.