scholarly journals Use of Dispersive Liquid-Liquid Microextraction and UV-Vis Spectrophotometry for the Determination of Cadmium in Water Samples

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
J. Pérez-Outeiral ◽  
E. Millán ◽  
R. Garcia-Arrona
Keyword(s):  
Water Samples ◽  
Limit Of Detection ◽  
Experimental Conditions ◽  
Cadmium Determination ◽  
A Value ◽  
Relative Standard ◽  
Potential Applicability ◽  
Dispersive Liquid Liquid Microextraction ◽  
Liquid Microextraction

A simple and inexpensive method for cadmium determination in water using dispersive liquid-liquid microextraction and ultraviolet-visible spectrophotometry was developed. In order to obtain the best experimental conditions, experimental design was applied. Calibration was made in the range of 10–100 μg/L, obtaining good linearity (R2 = 0.9947). The obtained limit of detection based on calibration curve was 8.5 μg/L. Intra- and interday repeatability were checked at two levels, obtaining relative standard deviation values from 9.0 to 13.3%. The enrichment factor had a value of 73. Metal interferences were also checked and tolerable limits were evaluated. Finally, the method was applied to cadmium determination in real spiked water samples. Therefore, the method showed potential applicability for cadmium determination in highly contaminated liquid samples.

scholarly journals Application of chemometrics for modeling and optimization of ultrasound-assisted dispersive liquid–liquid microextraction for the simultaneous determination of dyes

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Siroos Shojaei ◽  
Saeed Shojaei ◽  
Arezoo Nouri ◽  
Leila Baharinikoo
Keyword(s):  
Water Samples ◽  
Dynamic Range ◽  
Limit Of Detection ◽  
World Population ◽  
Simple Method ◽  
Relative Standard ◽  
Ultrasound Assisted ◽  
Dispersive Liquid Liquid Microextraction ◽  
Liquid Microextraction

AbstractAs the world population continues to grow, so does the pollution of water resources. It is, therefore, important to identify ways of reducing pollution as part of our effort to significantly increase the supply of clean and safer water. In this study, the efficiency of ultrasound-assisted dispersive liquid–liquid microextraction (UA-DLLME) as a fast, economical, and simple method for extraction malachite green (MG) and rhodamine B (RB) dyes from water samples is investigated. In optimal conditions, the linear dynamic range (LDR) for RB and MG is 7.5–1500 ng mL−1 and 12–1000 ng mL−1, respectively. The limit of detection (LOD) is 1.45 ng mL−1 and 2.73 ng mL−1, and limit of quantification (LOQ) is 4.83 ng mL−1 and 9.10 ng mL−1 for RB and MG, respectively. Extraction efficiency is obtained in the range of 95.53–99.60%. The relative standard deviations (RSD) in real water and wastewater samples are less than 3.5. The developed method is used successfully in the determination of RB and MG dyes from water samples and there are satisfactory results.

scholarly journals Determination of cobalt in water samples by atomic absorption spectrometry after pre-concentration with a simple ionic liquid-based dispersive liquid-liquid micro-extraction methodology

2010 ◽  
Vol 8 (3) ◽  
pp. 617-625 ◽  
Author(s):  
Hossein Abdolmohammad-Zadeh ◽  
Elnaz Ebrahimzadeh
Keyword(s):  
Ionic Liquid ◽  
Atomic Absorption Spectrometry ◽  
Atomic Absorption ◽  
Water Samples ◽  
Limit Of Detection ◽  
Absorption Spectrometry ◽  
Experimental Conditions ◽  
Flame Atomic Absorption ◽  
Relative Standard

AbstractA rapid dispersive liquid-liquid micro-extraction (DLLME) methodology based on the application of 1-hexylpyridinium hexafluorophosphate [C6py][PF6] ionic liquid (IL) as an extractant solvent was applied for the pre-concentration of trace levels of cobalt prior to determination by flame atomic absorption spectrometry (FAAS). 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was employed as a chelator forming a Co-PMBP complex to extract cobalt ions from aqueous solution into the fine droplets of [C6py][PF6]. Some effective factors that influence the micro-extraction efficiency include the pH, the PMBP concentration, the amount of ionic liquid, the ionic strength, the temperature and the centrifugation time which were investigated and optimized. In the optimum experimental conditions, the limit of detection (3s) and the enrichment factor were 0.70 µg L−1 and 60, respectively. The relative standard deviation (RSD) for six replicate determinations of 50 µg L−1 Co was 2.36%. The calibration graph using the pre-concentration system was linear at levels 2–166 µg L−1 with a correlation coefficient of 0.9982. The applicability of the proposed method was evaluated by the determination of trace amounts of cobalt in several water samples.

scholarly journals Sensitive Determination of Terazosin in Pharmaceutical Formulations and Biological Samples by Ionic-Liquid Microextraction Prior to Spectrofluorimetry

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Mohsen Zeeb ◽  
Mahdi Sadeghi
Keyword(s):  
Ionic Liquid ◽  
Ionic Strength ◽  
Biological Samples ◽  
Limit Of Detection ◽  
Pharmaceutical Formulations ◽  
Experimental Conditions ◽  
Relative Standard ◽  
Common Ion ◽  
Liquid Microextraction

An efficient and environmentally friendly sample preparation method based on the application of hydrophobic 1-Hexylpyridinium hexafluorophosphate [Hpy][PF6] ionic liquid (IL) as a microextraction solvent was proposed to preconcentrate terazosin. The performance of the microextraction method was improved by introducing a common ion of pyridinium IL into the sample solution. Due to the presence of the common ion, the solubility of IL significantly decreased. As a result, the phase separation successfully occurred even at high ionic strength, and the volume of the settled IL-phase was not influenced by variations in the ionic strength (up to 30% w/v). After preconcentration step, the enriched phase was introduced to the spectrofluorimeter for the determination of terazosin. The obtained results revealed that this system did not suffer from the limitations of that in conventional ionic-liquid microextraction. Under optimum experimental conditions, the proposed method provided a limit of detection (LOD) of 0.027 μg L−1and a relative standard deviation (R.S.D.) of 2.4%. The present method was successfully applied to terazosin determination in actual pharmaceutical formulations and biological samples. Considering the large variety of ionic liquids, the proposed microextraction method earns many merits, and will present a wide application in the future.

Vortex-Assisted Dispersive Liquid–Liquid Microextraction Coupled with Deproteinization for Determination of Nateglinide in Human Plasma Using HPLC/UV

2020 ◽  
Author(s):  
Mohamed A Hammad ◽  
Amira H Kamal ◽  
Reham E Kannouma ◽  
Fotouh R Mansour
Keyword(s):  
Human Plasma ◽  
High Performance ◽  
Limit Of Detection ◽  
Signal To Noise Ratio ◽  
Cost Effective ◽  
Salt Addition ◽  
Relative Standard ◽  
Dispersive Liquid Liquid Microextraction ◽  
Liquid Microextraction

Abstract A validated method for preconcentration and determination of nateglinide in plasma was developed using vortex-assisted dispersive liquid–liquid microextraction. Different variables that affect extraction efficiency were studied and optimized, including type and volume of extractant, type and volume of disperser, pH of diluent, salt addition effect, centrifugation and vortex time. Nateglinide was extracted using 30 μL of 1-octanol as an extractant and 200 μL of methanol as a disperser. The enrichment factor reached 330 under the optimum conditions. High-performance liquid chromatography/ultraviolet was used for detection using phosphate buffer (pH 2.5, 10 mM): acetonitrile (45:55, v/v) as a mobile phase at a flow rate of 1 mL/min. The method was linear over the range of 50–20,000 ng/mL with a limit of detection of 15 ng/mL (signal-to-noise ratio = 3). Intra- and inter-day precision had %relative standard deviation <6% (n = 3) and the %recoveries were found to be between 102.5 and 105.9%. The proposed method is simple, sensitive, eco-friendly, cost-effective and powerful for microextraction of nateglinide from human plasma samples.

Chitosan–Zinc Oxide Nanoparticles Combined with Dispersive Liquid–Liquid Microextraction for the Determination of BTEX in Water Samples

2015 ◽  
Vol 68 (3) ◽  
pp. 481 ◽  
Author(s):  
Mostafa Khajeh ◽  
Leyla Azarsa ◽  
Mansoureh Rakhshanipour
Keyword(s):  
Zinc Oxide ◽  
Water Samples ◽  
Zinc Oxide Nanoparticles ◽  
Solid Phase ◽  
Oxide Nanoparticles ◽  
Flame Ionization ◽  
Relative Standard ◽  
Dispersive Liquid Liquid Microextraction ◽  
Liquid Microextraction

In this study, chitosan–zinc oxide nanoparticles were used as an adsorbent matrix for solid-phase extraction and combined with dispersive liquid–liquid microextraction (SPE–DLLME) for determination of benzene, toluene, ethylbenzene, and xylene isomers (BTEX) in water samples. The eluent of SPE was used as the dispersive solvent of the DLLME for further purification and enrichment of the BTEX prior to gas chromatography-flame ionization detector analysis. The effect of variables, including amount of adsorbent, sample and eluent flow rate, type and volume of extraction and dispersive solvent, salt concentration, and extraction time, was investigated and they were optimized. Under the optimum conditions, good linearity for all BTEX with determination coefficients in the range of 0.9993 < r2 < 0.9997, suitable precision (1.4 % < RSD <1.9 %; where RSD refers to relative standard deviation), and low detection limits (0.5–1.1 µg L–1) were achieved. The current chitosan–zinc oxide nanoparticles SPE–DLLME procedure combines the advantages of SPE and DLLME, and was applied for determination of BTEX in water samples and acceptable recoveries were obtained.

scholarly journals Extraction and Determination of Oxymatrine Pesticide in Environmental Sample and in its Formulation using High-Performance Liquid Chromatography

2020 ◽  
Vol 8 (2) ◽  
pp. 1-7
Author(s):  
Ihsan M. Shaheed ◽  
Saadiyah A. Dhahir
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Water Samples ◽  
High Performance ◽  
Limit Of Detection ◽  
Limit Of Quantification ◽  
Chromatography Method ◽  
Relative Standard ◽  
Dispersive Liquid Liquid Microextraction

The quinolizindine alkaloid compound, oxymatrine pesticide, was analysis in the river water samples collected from different agriculture areas in the Iraqi city of Kerbala and also in its formulation using developed reverse-phase high-performance liquid chromatography method. Acetonitrile:methanol (60:40 v/v) was chosen as mobile phase at pH (7.0), flow rate 0.5 mL/min, and 20 µL as volume injection. Modified ecological-friendly method, dispersive liquid-liquid microextraction, was used for the extraction of oxymatrine from water samples. Linearity study was constructed from 0.1 to 70 μg/mL at λmax 205 nm. The limit of detection and limit of quantification were 0.025 and 0.082 μg/mL, respectively, and the relative standard deviation (RSD) % was 0.518%. Three spiked levels of concentration (20.0, 40.0, and 70.0 μg/mL) were used for the validation method. The percentage recovery for the three spiked samples was ranged between 98.743 and 99.432 and the RSD% was between 0.051 and 0.202%, the formulation studies of oxymatrine between 99.487 and 99.798, and the RSD% was ranged from 0.045 to 0.057%. The developed method can be used accurately and selectively for the determination of oxymatrine in environmental samples and in the formulation.

Dispersive Liquid-Liquid Microextraction Coupled with Gas Chromatography for the Determination of Orthochlorophenol in Environmental Water Samples

2012 ◽  
Vol 518-523 ◽  
pp. 1379-1382
Author(s):  
Ying Chun Yang ◽  
Qian Sun ◽  
Chong Shu Yi ◽  
Zhi Xiang Ye ◽  
Li Mo
Keyword(s):  
Gas Chromatography ◽  
Water Samples ◽  
Environmental Water ◽  
Environmental Water Samples ◽  
Extraction Solvent ◽  
Salt Addition ◽  
Relative Standard ◽  
Dispersive Liquid Liquid Microextraction ◽  
Liquid Microextraction

A rapid and effective method, the dispersive liquid-liquid microextraction(DLLME) with gas chromatography, has been developed for the extraction and determination of OCP in environmental water samples. The factors relevant to the efficiency of DLLME were investigated and optimized. Under the optimum conditions, such as 150μL of dichloromethane as extraction solvent, 1.2 mL acetone as dispersive agent, 8 minutes extraction time, and without salt addition, the linear response of this method was in the range of 0.5～5000μg L−1 (r = 0.9981), the relative standard deviation (RSD) for 500μg L−1 and 1000μg L−1 of OCP was 5.2% and 12.6% (n = 6), respectively. The detection limit (3σ) was 0.08 μg L−1. The developed method was successfully applied to the determination of trace amount of OCP in three kinds of real environmental water samples, the spiked recoveries were in the range of 87.4%～108.0%.

scholarly journals Vortex-assisted liquid–liquid microextraction combined with spectrophotometry for the determination of trace nitrite in water samples

2017 ◽  
Vol 17 (5) ◽  
pp. 1225-1231 ◽  
Author(s):  
Yang Jiao ◽  
Jianping Yu ◽  
Yaling Yang
Keyword(s):  
Organic Solvent ◽  
Water Samples ◽  
Limit Of Detection ◽  
Environmental Water ◽  
Cationic Dye ◽  
Optimum Conditions ◽  
Relative Standard ◽  
Optimized Conditions ◽  
Liquid Microextraction

A vortex-assisted liquid–liquid microextraction (VALLME) method using isooctanol as extractant followed by spectrophotometry was developed for the extraction and determination of trace nitrite in water samples. The method is based on selective ion-pairing complex (I3− MG+) formation of triiodideanion I3− with cationic dye malachite green (MG) at pH 3.0, and its subsequent extraction in an organic solvent. The extracted organic solvent-rich phase is diluted with methanol, and its absorbance is measured against an analyte blank at 630 nm. The variables affecting VALLME efficiency were investigated, and a set of optimized conditions was obtained. Under the optimum conditions, the linear range of nitrite was from 1.0 to 100 ng mL−1. The relative standard deviations (n = 10) were 2.1–3.9% and the limit of detection was 0.5 ng mL−1 and was successfully applied to the determination of nitrite in environmental water.

Ultrasonic-Assistant Dispersive Liquid-Liquid Microextraction Based on Solidification of Floating Organic Droplet Method for Quick Determination of Polycyclic Aromatic Hydrocarbons in Soils

2012 ◽  
Vol 190-191 ◽  
pp. 603-608 ◽  
Author(s):  
Chen Zhang ◽  
Long Jiang ◽  
Chong Meng ◽  
Xiao Peng Li ◽  
Yu Li
Keyword(s):  
Limit Of Detection ◽  
Soil Samples ◽  
Relative Standard ◽  
Polycyclic Aromatic ◽  
Ultrasound Assisted ◽  
Dispersive Liquid Liquid Microextraction ◽  
Liquid Microextraction ◽  
Quick Determination ◽  
Hydrocarbons In Soils

An ultrasound-assisted dispersive liquid-liquid micro-extraction method based on solidification of floating organic drop (UAE/DLLME/SFO) was established for the determination of PAHs in soils. Dichloromethane was used as solvent for the analytes in the soil by ultrasonic assistant extraction (UAE), the solvent was purified and concentrated by silica gel column chromatography and nitrogen flowing concentrator, respectively. The recoveries of the method were in the range 46.22-101.86%, and the relative standard deviations (RSD) were 3.03-7.80%. The linear range was 0.02-0.4mg/kg（0.02-0.5mg/kg）, and the limit of detection (LOD) was 0.17-29.13µg/kg. The method was applied to the real soil samples around wells of an oilfield; the relative recoveries of the ANY, ANA, FLU, PHE, ANT, FLT, PYR, BaA were 47.12-116.96%, while the recoveries of NAP, CHR, BbF, BkF, BaP, DBA, BPE, IPY were 17.75-63.29%.

scholarly journals Determination of three phenoxyacid herbicides in environmental water samples by the application of dispersive liquid-liquid microextraction coupled with micellar electrokinetic chromatography

2013 ◽  
Vol 11 (3) ◽  
pp. 394-403 ◽  
Author(s):  
Yanling Ma ◽  
Yingying Wen ◽  
Jinhua Li ◽  
Hua Wang ◽  
Yangjun Ding ◽  
...  
Keyword(s):  
Water Samples ◽  
Micellar Electrokinetic Chromatography ◽  
Background Electrolyte ◽  
Environmental Water ◽  
Environmental Water Samples ◽  
Electrokinetic Chromatography ◽  
Relative Standard ◽  
Dispersive Liquid Liquid Microextraction ◽  
Liquid Microextraction

AbstractAbstract An efficient method based on dispersive liquid-liquid microextraction coupled with micellar electrokinetic chromatography has been developed for determination of three phenoxyacid herbicides (PAs) of 2,4-dichlorophenoxybutyric acid (2,4-DB), dicamba and 2,4-dichlorophenoxyacetic acid (2,4-D), in environmental water samples. The types and volumes of extracting and dispersing solvents, ionic strength, extraction and centrifugation time and centrifugation speed were investigated. Successful separation of the three PAs was achieved within 7 min, by using the background electrolyte solution consisting of 10 mmol L−1 sodium tetraborate, 25 mmol L−1 sodium dodecyl sulfate and 15% (v/v) methanol, at pH 9.75. Excellent analytical performances were attained, such as good linear relationships (R ≥0.9993) between peak area and concentration for each PAs from 10–1000 ng mL−1, limits of detection of 1.56–1.91 ng mL−1, and intra-day precisions at two spiked levels in terms of migration time and peak area within the range of 0.22–0.42% and 3.88–6.39%, respectively. Enrichment factors of 2,4-DB, dicamba and 2,4-D were 180, 151 and 216, respectively. The method recoveries obtained at fortified 20.0, 50.0 and 100.0 ng mL−1 for lake, river and reservoir water samples varied from 67.91 to 119.07% with the relative standard deviation of 1.47–6.89%. Graphical abstract

Sign in / Sign up

Export Citation Format

Share Document