Facultade de Fisioterapia

Chemometric approach for the optimization of a flow injection manifold applied to the determination of total mercury by cold vapor-AAS

Authors: Jose Luis Capelo, Isela Lavilla, Carlos Bendicho

Journal: Atomic Spectroscopy, 21: 229-233, 11/2000

DOI:


Abstract

A flow injection manifold was optimized using factorial design for the determination of mercury in seafood after microwave- assisted digestion by cold vapor atomic absorption spectrometry. The 2v5·1 fractional factorial allowed to estimate main factor and two-factor interactions with only 16 experiments. The HCl flow rate displayed the highest influence on sensitivity, the effect being positive and independent of other factors. The sodium borohydride concentration showed a significant negative effect, which could not be individually interpreted as there was interaction between the reducing agent concentration and the reducing agent flow rate. This interaction arose from the different influence of the reducing agent concentration depending on the reducing agent flow rate. Low reducing agent concentration together with high reducing agent flow rate is recommended. The HCl concentration and carrier gas flow rate did not show any significant effect. With a sample loop of 500 μL, a LOD of 0.4 μg L·1 could be reached, the precision expressed as the relative standard deviation for 20 μg L·1 Hg solution being 1.5%. The manifold was applied to the determination of total Hg in five seafood samples, using microwave-assisted decomposition with the HNO3 + H2O2 mixture. The method was validated against two certified reference materials.

Chemometric approach for the optimization of a flow injection manifold applied to the determination of total Hg in seafood by cold vapor AAS. Available from: https://www.researchgate.net/publication/289018407_Chemometric_approach_for_the_optimization_of_a_flow_injection_manifold_applied_to_the_determination_of_total_Hg_in_seafood_by_cold_vapor_AAS [accessed Sep 11, 2017].