Ultrasound-assisted emulsification microextraction of trace amounts of Co and Mn ions prior to flame atomic absorption spectrometry

Abstract

O presente trabalho descreve um procedimento para emulsificação-microextração de quantidades traço de íons cobalto e manganês sem uso de ligantes, assistido por ultrasom, em amostras de água. Os metais extraídos foram determinados por espectrometria de absorção atômica em chama (FAAS). Foram estudados e otimizados diversos fatores que influenciam a eficiência de extração de íons cobalto e manganês, tais como tipo e volume do solvente de extração, pH, tempo de extração, temperatura de extração e força iônica. Íons cobalto e manganês foram extraídos em um meio emulsificado acusticamente com 20,0 mL de tetracloreto de carbono. Os limites de detecção foram 0,8 e 0,5 ng mL -1 para Co(II) e Mn(II), respectivamente (3 S b /m). Oito determinações em replicata de uma mistura de 100,0 ng mL -1 de cobalto e 50,0 ng mL -1 de manganês resultaram em absorbâncias média de 0,055 e 0,061 com desvios padrão relativos de 3,2% e 2,9%, respectivamente. O procedimento proposto foi aplicado com sucesso na determinação de cobalto e manganês em amostras de água.The present work reports a procedure based on ligandless-ultrasound-assisted emulsificationmicroextraction of trace amounts of cobalt and manganese ions in water samples prior to flame atomic absorption spectrometry determination (FAAS). Different factors influencing the extraction efficiency of cobalt and manganese ions, such as type and volume of the extraction solvent, pH, extraction time, extraction temperature, and ionic strength were studied and optimized. Cobalt and manganese ions were extracted in an acoustically emulsified media by 20.0 µL carbon tetrachloride. The limits of detection were 0.8 and 0.5 ng mL -1 for Co(II) and Mn(II), respectively (3S b /m). Eight replicate determinations of a mixture of 100.0 ng mL -1 cobalt and 50.0 ng mL -1 manganese gave a mean absorbance of 0.055 and 0.061 with relative standard deviations of 3.2 and 2.9%, respectively. The proposed procedure was successfully applied to determination of cobalt and manganese in water samples.

Ultrasound-Assisted Emulsification Microextraction Based on Solidification Floating Organic Drop Trace Amounts of Manganese Prior to Graphite Furnace Atomic Absorption Spectrometry Determination

“…As can be seen, the present method has higher enrichment factor than other methods such as cloud point extraction (CPE) [ 19 ], single-drop microextraction (SDME) [ 20 ], and dispersive liquid-liquid microextraction (DLLME) [ 21 ]. This method also has a lower limit of detection than CPE [ 19 ], solid phase extraction (SPE) [ 22 ], ligandless-ultrasound-assisted emulsification microextraction (LL-USAEME) [ 23 ], and DLLME [ 21 ] methods. Thus it is suitable for ultra trace analysis of manganese in aqueous samples.…”

Ultrasound-assisted surfactant-enhanced emulsification microextraction combined with hplc for the determination of estrogens in water

“…37 Mohammadi et al 38 have used ultrasound to assist with emulsification microextraction of trace amounts of Co and Mn ions in water. The ultrasonication times in the range of 0-15min were evaluated at 25 °C.…”

Determination of copper, nickel, manganese and cadmium ions in aqueous samples by flame atomic absorption spectrometry after simultaneous coprecipitation with Co(OH)2

“…The monitoring of the levels of heavy metal ions in environmental samples is an important part of analytical chemistry due to their positive or negative influences on the human body (Hedberg et al, 2011;Mohammadi et al, 2011;Tobiasz et al, 2012). Some metals such as manganese and copper are essential micronutrients and have a variety of biochemical functions in all living organisms.…”