Dispersive liquid-liquid microextraction based on solidification of floating organic drop for simultaneous separation/preconcentration of nickel, cobalt and copper prior to determination by electrothermal atomic absorption spectrometry

Abstract

Recebido em 11/3/12; aceito em 18/7/12; publicado na web em 7/12/12 A dispersive liquid-liquid microextraction based on solidification of floating organic drop for simultaneous extraction of trace amounts of nickel, cobalt and copper followed by their determination with electrothermal atomic absorption spectrometry was developed. 300 µL of acetone and 1-undecanol was injected into an aqueous sample containing diethyldithiocarbamate complexes of metal ions. For a sample volume of 10 mL, enrichment factors of 277, 270 and 300 and detection limits of 1.2, 1.1 and 1 ng L −1 for nickel, cobalt and copper were obtained, respectively. The method was applied to the extraction and determination of these metals in different water samples.

Trace nickel analysis in water samples via paper-based devices coupled with co-precipitation

“…The conventional analytical methods for the determination of Ni including inductively coupled plasma optical emission spectrometry (ICP-OES), 4 electrothermal atomic absorption spectrometry, 5 HPLC/ UV-VIS spectrophotometer, 6,7 voltammetry 8 and flame atomic absorption spectrometry 9,10 are very expensive and have limited accessibility in most developing countries. Thus, low cost, portable, simple, sensitive and easily accessible devices are required in developing countries for environmental monitoring.…”

Microfluidic paper-based analytical devices coupled with coprecipitation enrichment show improved trace analysis of copper ions in water samples

“…Several separation-enrichment techniques have been reported for conventional instrumental analyses. These include preconcentration techniques such as liquid-liquid extraction, 18,19 membrane filtration, 20,21 microextraction, 22,23 cloud point extraction, [24][25][26] ion exchange, 27 solid-phase extraction (SPE), 28,29 and coprecipitation. 30,31 Some of the preconcentration techniques are also coupled with μ-PADs, which include a heating method, 32,33 ion concentration polarization, 34 and a pumping system.…”

Ultrasonic supramolecular microextration of nickel (II) as N,N′-Dihydroxy-1,2-cyclohexanediimine chelates from water, tobacco and fertilizer samples before FAAS determination

“…In order to achieve accurate determination of nickel, sample pretreatment is an important step to purify the sample solution and to preconcentrate the analyte before the available instrumental analysis [10,11]. Several procedures for samples pretreatments have been developed including; solid phase extraction [8][9][10][11], cloud point extraction [12], dispersive liquid-liquid microextraction [13,14]. In addition, an online sonodigestion method was applied to extract nickel from water samples before the analysis by flame atomic absorption spectrometry [15].…”