Single-vial preconcentration and cold vapor generation for the determination of Hg(II) in water samples of different salinities.

In this work, a single-vial methodology for the extraction and cold vapor generation of mercury(II) was developed, followed by the determination of the analyte by atomic absorption spectrometry, with application in water samples of different salinities. L-cystine-modified FeO nanoparticles (2LcysMNP) were used as sorbent material in the magnetic solid phase extraction (MSPE) in the same flask in which the mercury vapor generation step was performed using a handmade gas-liquid separator developed in our laboratory. The main conditions for extraction, pre-concentration, and cold vapor generation of mercury were optimized.

Renewable column on-line magnetic preconcentration of Cd(II) using FeO nanoparticles functionalized with l-glutamine for determination by flame atomic absorption spectrometry.

This work reports the development of a flow injection analysis (FIA) system for online magnetic preconcentration and determination of Cd(II) in water by flame atomic absorption spectrometry (F AAS). Magnetic nanoparticles of FeO, functionalized with l-glutamine (GlnMNP), were synthesized and used as a support for Cd(II) retention and preconcentration. Each measurement cycle was performed through online complexation of Cd(II) by l-glutamine attached to FeO magnetic nanoparticles at pH 10.

Evaluation of Copper and Manganese Concentrations in Commercial Fruit Juices and Nectars Consumed in Brazil by GF AAS.

The present work proposes a simple method for direct determination of Cu and Mn in commercial fruit juices and nectars by graphite furnace atomic absorption spectrometry (GF AAS). We analyzed samples of different flavors (orange, mango, passion fruit, peach, and grape) and brands of Brazilian commercial fruit juices and nectars. We also carried out a study to define a suitable temperature program and to optimize the calibration conditions.