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•Ultrasound energy used for the advance extraction methodology for enrichment of analyte.•To overcome the hazardous effect of organic solvent dual dispersive ionic liquid based ...microextraction was developed.•The neurological disorders patients have higher levels of Cu ion in serum samples than normal referents.
An innovative dual dispersive ionic liquid based on ultrasound assisted microextraction (UDIL-μE), for the enrichment of trace levels of copper ion (Cu2+), in serum (blood) of patients suffering from different neurological disorders. The enriched metal ions were subjected to flame atomic absorption spectrometry (FAAS). In the UDIL-μE method, the extraction solvent, ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate C4mimPF6, was dispersed into the aqueous samples using an ultrasonic bath. The(PAN) 1-(2-pyridylazo)-2-naphthol was used as ligand for the complexation of Cu ion in IL (as extracting solvent). The various variables such as sonication time, pH, concentration of complexing agent, time and rate of centrifugation, IL volume that affect the extraction process were optimized. The enhancement factor (EF) and detection limit (LOD) was found under favorable condition was 31 and 0.36μgL−1, respectively. Reliability of the proposed method was checked by relative standard deviation (%RSD), which was found to be <5%. The accuracy of developed procedure was assured by using certified reference material (CRM) of blood serum. The developed procedure was applied successfully to the analysis of concentration of Cu ion in blood serum of different neurological disorders subjects and referents of same age group. It was observed that the levels of Cu ion was two folds higher in serum samples of neurological disorders patients as related to normal referents of same age group.
In this study, a sample preparation method based on ultrasonic assisted acid digestion (UAD) has been evaluated for total heavy metals (Cd, Cr, Ni and Pb) determination in different environmental ...(soil, sediment and sewage sludge), and biological (fish muscles, vegetables and grains) samples, using electrothermal atomic absorption spectrometry (ETAAS). The investigated parameters influencing UAD such as presonication time, sonication time, temperature of ultrasonic bath, and different acid mixtures were fully optimized, whereas power was maintained constant at 100% of nominal power of ultrasonic bath. Six different sets of above parameters were applied on six certified reference materials (CRMs) having different matrices. The accuracy of the method was also tested by comparing the results with those obtained from conventional hot plate assisted acid digestion method on same CRMs. Analytical results for HMs by both methods showed no significant difference at 95% confidence limit (
p
<
0.05). Recoveries of HMs ranging from 96.2% to 102% and 96.3% to 98.6% were obtained from biological and environmental samples, respectively. The average relative standard deviation of UAD method varied between 3.5% and 8.2%, depending on the analyte.
It is reported in literature that zinc (Zn2+) has antidepressant activity. In present study Zn2+ was analyzed in blood serum of male patients having various psychiatric disorders (schizophrenia, ...depression, bipolar). As it is usually present in trace levels. Hence a novel, environmental friendly, dual-cloud point extraction (d-CPE) method was developed for the enrichment of its trace levels in acid digested serum samples. In the first step of d-CPE, Zn2+ was complexed with 1-(2-pyridylazo)-2-naphthol (PAN), and the complex was entrapped in a nonionic surfactant (Triton X-114). After achieving cloud point by heating, the mixture was separated into two layers i.e. aqueous and surfactant-rich by centrifugation. In second step of d-CPE, the analyte complex in the surfactant-rich phase was treated wih acid to extract back the metal analytes in acidic aqueous phase, the mixture was again heated upto cloud point and the whole procedure was repeated. This time the aqueous phase, having the metals, was taken and subjected to FAAS using conventional nebulization. The accuracy of the developed methodologies (conventional and d-CPE), were verified by their application to certified reference material of serum (CRM). Reliability of the method was checked by relative standard deviation (%RSD), which was found to be <5%. The limit of detection and limit of quantification were calculated for the proposed method as 1.09μg/L, and 3.63 respectively and enhancement factor was found to be 40. The developed procedure was successfully applied to the serum samples of patients (male) having different psychiatric disorders and non-psychiatric control subjects for the determination of Zn2+.
A simple vortex-assisted modified dispersive liquid-liquid microextraction procedure is proposed for the enrichment of cadmium (Cd+2) in surface (stored rainwater) and groundwater of the Tharparkar ...district in Pakistan, before analysis by flame atomic absorption spectrometry. Ammonium pyrrolidinedithiocarbamate was used as a ligand to make a hydrophobic complex of Cd+2, which was extracted in an ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate), and the nonionic surfactant Triton X-114 was applied as a dispersing medium. The contents of tubes were shaken for different time intervals on a vortex mixer to enhance extraction efficiency. A multivariate strategy was used to simultaneously evaluate seven factors including, concentration of the complexing reagent, pH, amounts of ionic liquid and Triton X-114, vortex shaking time, centrifugation time and extracting solution for their influence on the percentage recovery of the analyte. The important variables were further optimized by central composite design. The preconcentration factor and LOD were observed as 76.9 and 0.048 µg/L, respectively. The Certified Reference Material SRM1643e was used to check the validity of the developed method, and the RSD was found to be 4.02%. The proposed technique was successfully applied for the enrichment of Cd+2 in groundwater and surface water samples from the southeastern part of Pakistan. The observed results revealed that the concentration of Cd+2 in groundwater was higher than the World Health Organization recommended value of 3 µg/L for drinking water. For adults weighing approximately 60 kg, consumption of groundwater for drinking and other domestic purposes would provide levels of Cd+2 that are 2- to 3-fold higher than the provisional maximum tolerable daily intake.
A novel switchable solvent (SS) extraction methodology has been used for the enrichment of aluminium (Al) in acid‐digested blood samples of patients with neurological disorders before proceeding to ...flame atomic absorption spectrometry. 1,8‐Diazabicyclo5.4.0undec‐7‐ene and decanol in combination made a SS which reversibly changes from hydrophobic (nonpolar) to hydrophilic (polar) according to switch‐on and switch‐off phenomena in aqueous medium by exposure to anti‐solvent trigger (CO2). The SS polar micro‐emulsion was switched on by bubbling CO2, and switched off by heating from 40 to 70°C with exposure to N2 gas. The changes obtained in the structure and physical properties of the SS due to switching from lower polarity to higher polarity were investigated using Fourier transform infrared spectroscopic analysis. The SS was effectively analysed as an extractive medium for hydrophobic chelate of Al with 3,5,7,2,4‐pentahydroxyflavone (morin) and extracted in SS. Then hydrophobic enriched Al‐morin‐SS was treated with 1.0 M HNO3 and CO2 purging at various time intervals, switch to a miscible polar hydrophilic monophase state. The SS was easily recycled up to six times for further enrichment process. For the developed method, various parameters were optimized such as pH, volume of chelating reagent, CO2 purging time and pressure, and rate of heating. Under favourable conditions, enhancement factor and limit of detection were observed as 25 and 0.47 μg l−1, respectively, for 10 ml of samples/standards solution. The accuracy of the developed method was determined using certified reference material (SRM 3101a), with a standard addition procedure. The method was used for the pre‐concentration of Al in blood samples of patients with neurological disorders.
Innovative switchable polarity solvent, based on 1,8‐diazabicyclo5.4.0undec‐7‐ene and decanol, for enrichment of aluminium in biological samples prior to analysis by flame atomic absorption spectrometry
In the present study, various sequential extraction methods were applied to assess the mercury (Hg) contents bounded with different chemical fractions of coal samples, collected from four different ...seams of the blocks III and V in Thar coalfield, Pakistan. The BCR sequential extraction (BCR-SE) method and two alternative modified schemes (conventional and ultrasonic assisted single step extractions) were designed and applied on the same operating conditions for each individual BCR fraction. Proximate and elemental analyses of coal samples were also performed to point out the physicochemical characteristics of the Thar coal samples. Validation of the desired methodologies was checked by the standard addition method to the real coal samples. The Hg concentration in extractable fractions was determined by cold vapor atomic absorption spectrometer (CV-AAS). The proposed conventional (CSE) and ultrasonic assisted single step (USE) extraction methods were non-tedious and time saving, as the extraction time was reduced from 51h to 36h and 2h, respectively. The extraction efficiency of CSE and USE was comparable with those data obtained with the conventional BCR protocol. The relative mobility of Hg in coal samples obtained from different depths was found in the following increasing order: oxidizable fraction<reducible fraction<acid soluble fraction.
•To evaluate Hg fractions in coal of the Thar coalfield on the bases of different depths•The fractionation study was carried out by different extraction schemes.•Compare the BCR-SES with CSE and USE for the quantitative determination of Hg•Statistical techniques used to elucidate the Hg fractions and other parameters in coal samples
The aim of the current study is to evaluate the occurrence of arsenic in coal collected from Thar coalfield, Pakistan, and its behavior during the combustion. Fractionation of arsenic (As) in coal ...samples was carried out by Community Bureau of Reference sequential extraction scheme (BCR-SES) and single-step-based BCR method (BCR-SS). These methods are validated using the certified reference material of sediment BCR 701 and standard addition method. The stepwise fractions of As in laboratory-made ash (LMA) have been also investigated. The extractable As content associated with different phases in coal and LMA samples were analyzed by electrothermal atomic absorption spectrophotometer. The extraction efficiency of As by BCR-SS was slightly higher than BCR-SES, while the difference was not significant (p < 0.05). The BCR-SS method is a time-saving method because it can reduce the extraction time from 51 to 22 h. The As contents in LMA revealed that during combustion of the coal, >85 % of As may be released into atmosphere. The relative mobility of As in the coal samples was found in increasing order as follows: oxidizable fraction < reducible fraction < acid soluble fraction. The total and extractable As obtained by BCR-SES and BCR-SS were higher in coal samples of block III as compared to block V (p > 0.05).
The combined exposure of arsenic (As) and cadmium (Cd) causes more pronounced renal toxicity. The study aimed to evaluate the level of As and Cd in biological samples (blood and urine) of adults ...males, age ranged (30–50 years) exposed referent (ER) and exposed kidney patients (EKP), consumed contaminated drinking water of lake and smoking local cigarettes manufactured by tobacco plants grown on agricultural soil, irrigated with contaminated lake water. For comparative purpose age matched nonexoposed referent (NR) and nonexposed kidney patient (NKP), consumed municipal treaded water and smoking branded cigarette were also selected. The As and Cd levels in drinking water, biological samples, tobacco of branded and nonbranded cigarettes were analyzed using electrothermal atomic absorption spectrometry. The As and Cd concentrations in lake water were higher than the permissible limit recommended by the World Health Organization for drinking water. The As and Cd levels in local cigarette tobacco were found to be 3- to 4-folds higher than branded cigarettes. The biochemical parameters especially urinary N-acetyl-β-glucosaminidase (NAG) of ER, EKP, ER, and EKP subjects were studied as a biomarkers of renal dysfunction. The NAG values were found to be higher in EKP as compared to NKP (p < 0.01). The linear regressions showed higher correlations between As and Cd concentrations in water versus blood and urine samples of EKP (r = 0.71–0.78 and 0.68–0.72), as compared to NKP (p < 0.05).
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