Cobalt separation from water and food samples based on penicillamine ionic liquid and dispersive liquid-liquid microextraction before determination by AT-FAAS

Abstract

The cobalt compounds have adverse health effect on human and caused damage to the DNA cells, neurological and endocrine systems. Therefore, the separation and determination of cobalt in water and food samples must be considered. In this research, the (2S)-2-amino-3-methyl-3-sulfanylbutanoic acid (penicillamine) as a chelating agent mixed with ionic liquid (OMIM PF6) /acetone and used for extraction of cobalt from 50 mL of water samples by ultra-assisted dispersive liquid-liquid microextraction (USA-DLLME) at pH=6. Based on procedure, the samples were shaked for 5 min (25oC) and after complexation of cobalt ions by thiol and amine group of penicillamine, the ionic liquid phase separated in the bottom of the conical tube by centrifuging for 3.0 min. The upper liquid phase was vacuumed by the auto-sampler and the Co2+ ions back extracted from the ionic liquid/ penicillamine in acidic pH. Finally, the cobalt concentration in remained solution was determined by atom trap flame atomic absorption spectrometry (AT-FAAS). The main parameters such as the sample volume, the penicillamine amount, the ionic liquid amount and the shaking time were optimized. The linear range, the detection limit (LOD) and enrichment factor were obtained 1.5-62 μg L-1, 0.38 μg L-1 and 98.5, respectively (r = 0.9995, RSD%=2.2).

Synthesis and identification of meta-(4-bromobenzyloxy) benzaldehyde thiosemicarbazone (MBBOTSC) as novel ligand for cadmium extraction by ultrasound assisted-dispersive-ionic liquid-liquid micro extraction method

“…Synthesis of TSC is performed in different ways: a) it is a two-step pathway in which hydrazine reacts with isothiocyanate and the product with aldehyde or ketone, which leads to TSCs [9], b) it is the opposite of pathway a, ie hydrazine first reacts with aldehydes or ketones and then the resulting compound reacts with isothiocyanate [10], c) it is a 4-step process, in which hydrazine first reacts with carbon disulfide and the resulting intermediate reacts with methyl iodide to form methylhydrazine thiocarbamate, eventually nucleophilic substitution with amines and a condensation reaction with an aldehyde or ketone produces TSC [11]. In continuation of our research on the synthesis of various compounds [12][13][14][15] and recent report introducing penicillamine as a metal chelator [16], herein, MBBOTSC as ligand containing sulfur and nitrogen has proposed as cadmium chelator.…”

A novel double metal-dithizone functionalized polyurethane electrospun nanofiber and film for colorimetric determination of hexavalent chromium

“…However, unlike Zn 2+ , the presence of Co 2+ has hardly been mentioned in natural samples. 33,34 To make the DTZ/PU-NF more selective, we chose Co 2+ to react with DTZ in the first stage of this investigation. The colour changed from red to magenta after Cr 6+ was introduced to the testing area holding the DTZ-Co 2+ combination, which could not be seen when tested with other common metals prevalent in fruit juice as described in a wet analysis.…”