Development of a novel method based on extraction mediated by a semipermeable membrane to determine Cd and Cr in sugar by graphite furnace atomic absorption spectrometry.

This work proposes a novel method to determine the Cd(II) and Cr(III) content in commercial sugar samples. It is based on the extraction of the analytes (as ammonium pyrrolidine dithiocarbamate complexes) into a semipermeable membrane device (SPMD) filled with CHCl. After extraction, the SPMD was deployed and opened, and the analytes were recovered from the organic phase by back extraction with a 4.

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.

Synthesis and application of a new thiazolylazo reagent for cloud point extraction and determination of cobalt in pharmaceutical preparations.

The synthesis and characterization of the reagent 2-(5-bromothiazolylazo)-4-chlorophenol and its application in the development of a preconcentration procedure for cobalt determination using flame atomic absorption spectrometry after cloud point extraction is presented. This procedure is based on cobalt complexing and entrapment of the metal chelates into micelles of a surfactant-rich phase of Triton X-114. The preconcentration procedure was optimized by using a response surface methodology through the application of the Box-Behnken matrix.

Thermospray generation directly into a flame furnace--an alternative to improve the detection power in atomic absorption spectrometry.

Recent developments and applications in the production of thermosprays directly into flame furnaces to improve the analytical sensitivity in atomic absorption spectrometry are reviewed in this manuscript. Principles, characteristics, instrumentation, and applications of this analytical technique for trace elements determination in several matrices are discussed. The use of preconcentration procedures to allow low detection limits for ultra-trace levels using TS-FF-AAS is presented and current perspectives and future trends of this technique are also discussed.