Abstract (EN):
The so-called "multi-pumping flow systems" (MPFS), which rely on the utilization of solenoid-actuated micro-pumps (SAMPs) for introduction and propulsion of solutions, are a relatively recent development in the flow analysis field. They have already been coupled to several molecular spectrometric detectors with claimed advantages. However, the applicability and potentialities of their coupling to flame atomic spectrometric (FAS) detectors has never been studied. This work describes the study of coupling multi-pumping flow systems to flame atomic absorption spectrometers (FAAS) and flame (atomic emission) photometers (FP). The main purpose was to study the behavior of SAMPs when subjected to the aspiration effect inherent to nebulizers of FAS instrumentation (Venturi effect) and to evaluate the effects of the pulsed flow, a main characteristic of MPFS, over the efficiency of the nebulization and atomization processes. Based on these preliminary studies, several MPFS that enabled the on-line dilution of samples and/or the on-line addition of reagents (e.g., a releasing agent), two sample pre-treatment steps frequently required when using FAS detectors in analytical work, were developed. In this study, the analytical applicability has been demonstrated in the determination of Na in urine samples (using FP) and Ca and Mg in hair sample digests (using FAAS). The multi-pumping flow systems enable the configuration of simple analytical flow systems that are robust and capable of providing precise and accurate results with good sampling rates.
Language:
English
Type (Professor's evaluation):
Scientific
Contact:
aalmeida@ff.up.pt
No. of pages:
9