Determination of copper in human hair and tea samples after dispersive liquid-liquid microextraction based on solidification of floating organic drop (DLLME-SFO)

Abstract

proposto é simples, barato e altamente preciso. Neste estudo, a otimização de parâmetros experimentais que influenciam a extração, como tipo e volume dos solventes de extração e do dispersor, pH, quantidade de agente quelante e tempo de extração foi realizada normalmente usando uma abordagem passo-a-passo, na qual cada fator variou sequencialmente. O efeito dos íons interferentes na recuperação dos analitos também foi investigado. O gráfico de calibração foi linear no intervalo de 5-200 ng mL −1 , com limite de detecção de 3,4 ng mL −1. O desvio padrão relativo (RSD) foi 0,7% (n = 10, C = 2 ng mL -1 ) e o fator de enriquecimento, 28.A simple method of dispersive liquid-liquid microextraction-solidified floating organic drop (DLLME-SFO) prior to flame atomic absorption spectrometry was successfully used for separating and preconcentrating copper in human hair and tea samples. The proposed method was simple, cheap, and has high precision. In this study, optimization of experimental parameters influencing the extraction, such as type and volume of extraction and disperser solvents, pH, the amount of chelating agent and extraction time was normally carried out using a step-by-step approach, in which each factor was varied sequentially. The effect of the interfering ions on the analytes recovery was also investigated. The calibration graph was linear in the range of 5-200 ng mL . The relative standard deviation (RSD) was 0.7% (n = 10, C = 2 ng mL −1 ) and the enhancement factor was 28.Keywords: dispersive liquid-liquid microextraction, solidification, copper determination, tea and human hair analysis IntroductionTrace heavy metals are essential micro-nutrients and have a variety of biochemical functions in all living organisms. [1][2][3] Due to the positive and negative effects and the toxicity of trace heavy metals on human health and the environment, many researchers are interested in the analysis of trace metal contents of the environmental and the food samples. [4][5][6][7][8][9][10] Tea, one of the most widely consumed beverages in the world, is prepared from the young leaves of tea plants. It is considered as a healthy drink that has benefits including the prevention of many diseases. [11][12][13] Although copper is an essential trace element for humans and is an indispensable component for many enzyme systems, Cu can also act as a toxic metal to which a number of pathogenic characteristics have been attributed.14 Therefore, Cu contamination in tea leaves remains a concern, and researches should be done to ensure food safety from excessive Cu contamination.The determination of trace elements in human hair is of basic importance considering that the concentrations of these elements in hair can indicate the levels of these elements in the organism. Therefore, the determination of the metal contents in human hair can be used either as the index of the exposition for potentially toxic elements (poisoning) or as the information of the conditions of health of an individual. 15The accurate and sensitive determinations...

A New Dispersive Liquid–Liquid Microextraction Method for Preconcentration of Copper from Waters and Cereal Flours and Determination by Flame Atomic Absorption Spectrometry

“…This work a DLLME dispersive liquid-liquid microextraction, SFODME solidified floating organic drop microextraction, LL-DLLME ligandlessdispersive liquid-liquid microextraction, DLLME-SFO dispersive liquid-liquid microextraction-solidified floating organic drop, IL-DLLME ionic liquid dispersive liquid-liquid microextraction, HLLME homogeneous liquid-liquid extraction, CPE cloud point extraction, SPE solid phase extraction A comparison of the developed method with the other reported preconcentration methods for copper determination using FAAS is given in Table 3. By comparing the data in this table, it is clear that detection limit for the proposed method is better than or comparable to those obtained with other methods (Jamali et al 2007;Farajzadeh et al 2008Farajzadeh et al , 2009Acar and Kara 2014;Bahar and Zakerian 2012;Manzoori and Bavili-Tabrizi 2002;Ghaedi et al 2008;Sheibani et al 2011). Although some of these methods have better detection limits Ozcelik et al 2012;Şahin and Tokgöz 2010;Durukan et al 2011;Mohammadi et al 2009;Khani et al 2011), some of them need very large sample volumes (Ozcelik et al 2012;Şahin and Tokgöz 2010;Durukan et al 2011).…”

C18 dolgulu mini kolon kullanılarak doğal sulardan bakır ve demirin önderiştirilmesi ve alevli AAS ile tayini

“…Table 4 summarizes the comparison of the developed method with some existing methods coupled with FAAS detection for the determination of Fe and Cu. The limits of detection of the analytes are superior than or comparable to those acquired with other reported methods [15,[20][21][22][23][24]. Although some of these methods have better detection limits or higher preconcentration factors, they need large sample volumes [15,16,18,19,21,22].…”

A Method to Determination of Lead Ions in Aqueous Samples: Ultrasound-Assisted Dispersive Liquid-Liquid Microextraction Method Based on Solidification of Floating Organic Drop and Back-Extraction Followed by FAAS

“…Increase in ionic strength resulting from salt addition causes two opposite effects on the extraction efficiency: (1) the physical properties of the Nernst diffusion film can change by the presence of dissolved salt in water, and consequently, the diffusion rate of the analyte into the drop can decrease [ 29 ]; (2) the salting-out effect can cause an increase in the extraction efficiency [ 30 ]. In order to investigate the effect of ionic strength arising from salt addition, on performance of UA-DLLME-SFO-BE, various experiments were performed by adding varying amounts of NaCl from 0% to 4% (w/v).…”