scholarly journals Determination of Atropine Sulfate in Human Urines by Capillary Electrophoresis Using Chemical Modified Electrode as Electrochemiluminescence Sensor

2011 ◽  
Vol 2011 ◽  
pp. 1-6
Author(s):  
Min Zhou ◽  
Juan Mi ◽  
Yujie Li ◽  
Huashan Zhang ◽  
Yanjun Fang
Keyword(s):  
Capillary Electrophoresis ◽  
Phosphate Buffer ◽  
Platinum Electrode ◽  
High Sensitivity ◽  
Atropine Sulfate ◽  
Sulfate Concentration ◽  
Electrokinetic Injection ◽  
Relative Standard ◽  
Optimized Conditions

A Ru(bpy)3 2+-based electrochemiluminescence (ECL) detection coupled with capillary electrophoresis (CE) was developed for the determination of atropine sulfate on the basis of an Eu-PB modified platinum electrode as the working electrode. The analyte was injected to separation capillary of 50 cm length (25 μm i.d., 360 μm o.d.) by electrokinetic injection for 10 s at 10 kV. Parameters related to the separation and detection were discussed and optimized. It was proved that 10 mM phosphate buffer at pH 8.0 could achieve the most favorable resolution, and the high sensitivity of detection was obtained by using the detection potential at 1.15 V and 5 mM Ru(bpy)3 2+in 80 mM phosphate buffer at pH 8.0 in the detection reservoir. Under the optimized conditions, the ECL peak area was in proportion to atropine sulfate concentration in the range from 0.08 to 20 μg⋅mL−1with a detection limit of 50 ng⋅mL−1(3σ). The relative standard derivations of migration time and peak area were 0.81 and 3.19%, respectively. The developed method was successfully applied to determine the levels of atropine sulfate in urine samples of patients with recoveries between 90.9 and 98.6%.

Determination of Erythromycin and Haloperidol in Human Urine by Capillary Electrophoresis Online Coupled with Electrochemiluminescence Detection

2011 ◽  
Vol 343-344 ◽  
pp. 764-768 ◽  
Author(s):  
Bi Yang Deng ◽  
Yan Hui Kang ◽  
Lin Qiu Li ◽  
Ai Hong Shi
Keyword(s):  
Capillary Electrophoresis ◽  
Human Urine ◽  
Phosphate Buffer ◽  
Electrokinetic Injection ◽  
Ecl Cell ◽  
Optimized Conditions ◽  
Sensitive Method ◽  
Separation Buffer ◽  
Linear Concentration

This work developed a simple and sensitive method for the simultaneous determination of erythromycin (Ery) and haloperidol (Hal) in human urine by capillary electrophoresis with eletrochemiluminescence detection. Under optimized conditions, such as detection potential at 1.25 V, electrokinetic injection at 10 kV for 6 s, separation voltage at 10 kV, 15 mmol/L separation buffer with pH 6.5, 5 mmol/L Ru(bpy)32+ and 50 mmol/L phosphate buffer with pH 8.0 in the ECL cell, the linear concentration ranges for Ery and Hal were from 0.005 to 0.2 μg/mL and from 0.15 to 6.0 μg/mL, respectively. The detection limits (3σ) for Ery and Hal were 0.002 and 0.06 μg/mL, respectively. When the method was applied to determine Ery and Hal in human urine, the recoveries were 96.5% and 95.1% on an average, respectively.

scholarly journals New Spectrofluorimetric Method with Enhanced Sensitivity for Determination of Paroxetine in Dosage Forms and Plasma

2008 ◽  
Vol 3 ◽  
pp. ACI.S1053 ◽  
Author(s):  
Ibrahim A. Darwish ◽  
Sawsan M. Amer ◽  
Heba H. Abdine ◽  
Lama I. Al-Rayes
Keyword(s):  
High Sensitivity ◽  
Dosage Forms ◽  
Official Method ◽  
Factors Affecting ◽  
Pharmaceutical Tablets ◽  
Enhanced Sensitivity ◽  
Spectrofluorimetric Method ◽  
Relative Standard ◽  
Optimized Conditions

New simple spectrofluorimetric method with enhanced sensitivity has been developed and validated for the determination of the antidepressant paroxetine (PXT) in its dosage forms and plasma. The method was based on nucleophilic substitution reaction of PXT with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole in an alkaline medium (pH 8) to form a highly fluorescent derivative that was measured at 545 nm after excitation at 490 nm. The factors affecting the reaction was carefully studied and optimized. The kinetics of the reaction was investigated, and the reaction mechanism was presented. Under the optimized conditions, linear relationship with good correlation coefficient (0.9993) was found between the fluorescence intensity and PXT concentration in the range of 80-800 ng ml-1. The limits of detection and quantitation for the method were 25 and 77 ng ml-1, respectively. The precision of the method was satisfactory; the values of relative standard deviations did not exceed 3%. The proposed method was successfully applied to the determination of PXT in its pharmaceutical tablets with good accuracy; the recovery values were 100.2 ± 1.61%. The results obtained by the proposed method were comparable with those obtained by the official method. The proposed method is superior to the previously reported spectrofluorimetric method for determination of PXT in terms of its higher sensitivity and wider linear range. The high sensitivity of the method allowed its successful application to the analysis of PXT in spiked human plasma. The proposed method is practical and valuable for its routine application in quality control and clinical laboratories for analysis of PXT.

Electrochemiluminescence Determination of Pethidine by Capillary Electrophoresis Separation

2011 ◽  
Vol 361-363 ◽  
pp. 1914-1917
Author(s):  
Qian Xiang ◽  
Ying Gao ◽  
Feng Hui Xie
Keyword(s):  
Capillary Electrophoresis ◽  
Detection Limit ◽  
Applied Voltage ◽  
Phosphate Buffer ◽  
Determination Method ◽  
Capillary Electrophoresis Separation ◽  
Electrokinetic Injection ◽  
Sensitive Determination ◽  
Electrophoresis Separation

A sensitive determination method for pethidine based on capillary electrophoresis-electrochemiluminescence detection was described. Analysis conditions affecting separation and detection were discussed and optimized in detail. The mixture solution of 5 mmol/L Ru(bpy)32+ and 50 mmol/L phosphate buffer at pH 7.46 were added to the detection reservoir. End-column detection of pethidine was performed. Sensitive electrochemiluminescence detection was obtained at applied voltage of 1.20 V. A baseline separation of pethidine was achieved using a phosphate running buffer at pH 7.46 by electrokinetic injection for 10 s at 10 kV. A detection limit of 5.0×10-8 M (S/N=3) was achieved.

Atomic absorption determination of Hg (II), Cd (II), and As (III) in natural and waste water after preliminary group preconcentration

2019 ◽  
Vol 85 (2) ◽  
pp. 12-16
Author(s):  
I. V. Saunina ◽  
E. N. Gribanov ◽  
E. R. Oskotskaya
Keyword(s):  
Waste Water ◽  
Atomic Absorption ◽  
High Sensitivity ◽  
Distribution Coefficients ◽  
Neutral Medium ◽  
Atomic Absorption Determination ◽  
Absorption Determination ◽  
Relative Standard ◽  
Preliminary Group

The sorption of Hg (II), Cd (II), and As (III) by natural aluminosilicate is studied. It is shown that the mineral absorbs those toxicants in a rather wide pH range, quantitative extraction of analytes being achieved in a neutral or close to neutral medium (pH values range within 7.0 - 8.0; 6.3 - 7.5; 7.4 - 8.5 for Hg (II), As (III), and Cd (II), respectively). The effect of the time of phase contact on the degree of extraction of elements is shown. The sorption capacity of the mineral in optimal conditions of the medium acidity (0.06 mmol/g for mercury, 0.31 mmol/g for cadmium, and 0.52 mmol/g for arsenic) is determined. The distribution coefficients attain values of aboutnX 103-nX 104. A new combined method for determination of Hg (II), Cd (II), and As (III) in natural and waste water is developed and tested. The method consists in a preliminary group sorption concentration of the analytes by aluminosilicate, desorption of the analytes from the surface of the mineral and their subsequent atomic absorption determination. The correctness of the method is verified in analysis of spiked samples. The method is easy to use and exhibits high sensitivity, reproducibility and accuracy of analyte determination. The relative standard deviation does not exceed 0.13. Economic availability and possibility of using domestic sorption materials are the important advantages of the proposed procedure which can be used in the practice of laboratories monitoring the quality and safety of environmental objects.

Selective electromembrane extraction and sensitive colorimetric detection of copper(II)

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Wajid Ali Khan ◽  
Muhammad Balal Arain ◽  
Hashmat Bibi ◽  
Mustafa Tuzen ◽  
Nasrullah Shah ◽  
...  
Keyword(s):  
Applied Voltage ◽  
Colorimetric Detection ◽  
Environmental Water ◽  
Selective Extraction ◽  
Effective Parameters ◽  
Relative Standard ◽  
Electromembrane Extraction ◽  
Optimized Conditions ◽  
Donor Phase

AbstractIn this study, an extremely effective electromembrane extraction (EME) method was developed for the selective extraction of Cu(II) followed by Red-Green-Blue (RGB) detection. The effective parameters optimized for the extraction efficiency of EME include applied voltage, extraction time, supported liquid membrane (SLM) composition, pH of acceptor/donor phases, and stirring rate. Under optimized conditions, Cu(II) was extracted from a 3 mL aqueous donor phase to 8 µL of 100 mM HCl acceptor solution through 1-octanol SLM using an applied voltage of 50 V for 15 min. The proposed method provides a working range of 0.1–0.75 µg·mL−1 with 0.03 µg·mL−1 limit for detection. Finally, the developed technique was applied to different environmental water samples for monitoring environmental pollution. Obtained relative recoveries were within the range of 93–106%. The relative standard deviation (RSD) and enhancement factor (EF) were found to be ≤4.8% and 100 respectively. We hope that this method can be introduced for quantitative determination of Cu(II) as a fast, simple, portable, inexpensive, effective, and precise procedure.

Analysis of Synthetic Antioxidant in Food by Capillary Electrophoresis

2011 ◽  
Vol 361-363 ◽  
pp. 1855-1858 ◽  
Author(s):  
Qian Xiang ◽  
Ying Gao
Keyword(s):  
Capillary Electrophoresis ◽  
Amperometric Detection ◽  
Peak Height ◽  
Butylated Hydroxyanisole ◽  
Applied Potential ◽  
Synthetic Antioxidant ◽  
Separation Potential ◽  
Relative Standard ◽  
Capillary Electrophoretic

A capillary electrophoretic assay for determining synthetic antioxidant butylated hydroxyanisole in food has been developed. The extraction with 70% (v/v) methanol quantitatively extracted synthetic antioxidant. The separation was carried out by CZE using phosphate at a separation potential of 18 kV. Amperometric detection was achieved with an applied potential of 0.60 V. A linear relationship between the peak height and the concentration of the analyte was found in the range 1.8-180 µg/mL for BHA, with correlation coefficient of 0.994. The relative standard deviations of migration time and peak height were 0.19 and 5.3 %, respectively. The method developed was successfully applied for the determination of synthetic antioxidant butylated hydroxyanisole in food. Recovery of butylated hydroxyanisole was 93%.

Preconcentration and Determination of Lead by Solidification of Floated Organic Drop Coupled with Nanodrop Spectrophotometry

2013 ◽  
Vol 829 ◽  
pp. 825-830 ◽  
Author(s):  
Ali Mazloomifar ◽  
Nafiseh Khatibi
Keyword(s):  
Sea Water ◽  
Chelating Agent ◽  
Limit Of Quantification ◽  
Liquid Phase Microextraction ◽  
Relative Standard ◽  
Preconcentration Factor ◽  
Uv Visible ◽  
Optimized Conditions ◽  
Sample Vial

The liquid-phase microextraction based on solidification of floating organic microdrop coupled with UV-visible spectrophotometer for preconcentration and determination of lead in the aqueous samples has been developed. In this technique, 20μL of 1-undecanol containing dithizone as the chelating agent (10-3mol L-1) was transferred to the water samples containing lead ions, and the solution was stirred for 25 min. The sample vial was cooled in an ice bath for 5 min. The solidified extract was transferred into a conical vial where it melted immediately, and then the organic phase was analyzed by Nanodrop spectrophotometer. Factors that influence the extraction and complex formation, such as pH, concentration of dithizone, extraction time, effect of ionic strenght, temperature and stirring rate were optimized. Under the optimized conditions, a preconcentration factor of 356, detection limit of 0.006 μgL-1, limit of quantification 0.018 μgL-1and a good relative standard deviation of 2.1% were obtained. The procedure was applied to sea water, mineral water and well water.

scholarly journals Liquid Chromatographic Determination of Ampicillin Residues in Porcine Muscle Tissue by a Multipenicillin Analytical Method: European Collaborative Study

2002 ◽  
Vol 85 (4) ◽  
pp. 889-900 ◽  
Author(s):  
Eric Verdon ◽  
Pierric Couëdor ◽  
Pierre Maris ◽  
Michel Laurentie ◽  
P Batjoens ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Muscle Tissue ◽  
Phosphate Buffer ◽  
Collaborative Study ◽  
Porcine Muscle ◽  
Relative Standard ◽  
Liquid Chromatographic

Abstract A collaborative study involving 14 laboratories was conducted to determine residues of ampicillin in porcine muscle tissue by using a liquid chromatographic method developed for multipenicillin analysis that can quantitate 8 penicillin compounds (benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, nafcillin, oxacillin, cloxacillin, and dicloxacillin) at trace levels in muscle tissue. This method involves extraction of the penicillins with phosphate buffer, pH 9, followed cleanup and concentration on a C18 solid-phase extraction column and reaction with benzoic anhydride at 50°C and with 1,2,4-triazole and mercury(II) chloride solution, pH 9.0, at 65°C. The derivatized compounds are eluted isocratically on a C8 column with a mobile phase of acetonitrile and phosphate buffer (pH 6; 0.1M) containing sodium thiosulfate and the ion-pair reagent tetrabutylammonium hydrogen sulfate. The penicillins are detected by UV absorption at 325 nm. The limit of detection and the limit of determination (quantitation) of the method were calculated to be approximately 3–5 and 25 μg/kg, respectively, in accordance with the criteria of European Union (EU) Decision No. 93/256/EEC. In this first interlaboratory study, collaborators were instructed to monitor 4 different penicillin compounds (benzylpenicillin, phenoxymethylpenicillin, ampicillin, and amoxicillin) by analyzing 8 blind samples of muscle tissue in triplicate. These samples were prepared from 2 materials containing different concentrations of incurred ampicillin (63.5 μg/kg for material No. 1 and 358.1 μg/kg for material No. 2) and 1 blank material. The repeatability relative standard deviation and the reproducibility relative standard deviation were 10.2 and 17.4%, respectively, for material No. 1 and 7.0 and 16.0%, respectively, for material No. 2. These results demonstrate that the method is suitable for the determination of ampicillin residues in muscle tissue at the EU maximum residue limit (50 μg/kg) and above. However, the identification of positives by this procedure may need additional confirmation by techniques with greater specificity, such as liquid chromatography combined with mass spectrometry, or tandem mass spectrometry. Investigations regarding the basis of interlaboratory testing studies will further demonstrate the suitability of multiresidue methodology for detecting and quantitating other compounds in the family of penicillin antibiotics.

scholarly journals Determination of cyanide in bamboo shoots by microdiffusion combined with ion chromatography–pulsed amperometric detection

2018 ◽  
Vol 5 (4) ◽  
pp. 172128 ◽  
Author(s):  
Ming Ding ◽  
Kailiang Wang
Keyword(s):  
Ion Chromatography ◽  
Limit Of Detection ◽  
Correlation Coefficients ◽  
Amperometric Detection ◽  
High Sensitivity ◽  
Practical Method ◽  
Pulsed Amperometric Detection ◽  
Bamboo Shoots ◽  
Relative Standard

A practical method for the determination of cyanide in bamboo shoots has been developed using microdiffusion preparation integrated with ion chromatography–pulsed amperometric detection (IC-PAD). Cyanide was released from bamboo shoots after Conway cell microdiffusion, and then analysed by IC-PAD. In comparison with the previously reported methods, derivatization and ion-pairing agent addition were not required in this proposed microdiffusion combined with IC-PAD method. The microdiffusion parameters were optimized including hydrolysis systems, temperature, time, and so on. Under the optimum conditions, the linear range of the calibration curve for cyanide was 0.2–200.0 µg kg −1 with satisfactory correlation coefficients of 0.9996 and the limit of detection was 0.2 µg kg −1 ( S/N  = 3). The spiked recovery range was from 92.8 to 98.6%. The intra-day and inter-day relative standard deviations of cyanide were 2.7–14.9% and 3.0–18.3%, respectively. This method was proved to be convenient in operation with high sensitivity, precision and accuracy, and was successfully applied in the determination of cyanide in bamboo shoot samples.

scholarly journals Multiresidue Determination of Fluoroquinolones in Shrimp by Liquid Chromatography-Fluorescence-Mass Spectrometryn

2005 ◽  
Vol 88 (4) ◽  
pp. 1160-1166 ◽  
Author(s):  
Marilyn J Schneider ◽  
Luz Vazquez-Moreno ◽  
Maria del Carmen Bermudez-Almada ◽  
Ramon Barraza Guardado ◽  
Magdalena Ortega-Nieblas
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Standard Deviation ◽  
Phosphate Buffer ◽  
Fluorescence Detector ◽  
Relative Standard ◽  
Product Ions ◽  
Multiresidue Determination ◽  
Shrimp Tissue

Abstract An efficient multiresidue method for analysis of fluoroquinolones in shrimp has been developed in which quantitation by fluorescence and confirmation by Multiple Stage Mass Spectrometry (MSn) is achieved simultaneously. In this method, shrimp tissue is extracted with ammoniacal acetonitrile and the extract is defatted and then evaporated. After dissolution in basic phosphate buffer, fluoroquinolones in the extract are separated by liquid chromatography and quantitated, taking advantage of their intense fluorescence. Eluate from the fluorescence detector enters the MSn, which allows for confirmation by monitoring ratios of 2 prominent product ions in the MS3 or MS2 spectrum. Using this method, 8 fluoroquinolones have been analyzed in shrimp samples fortified at 10, 25, 50, or 100 ppb levels. Recoveries for desethyleneciprofloxacin, norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, orbifloxacin, sarafloxacin, and difloxacin ranged from 75 to 92%, with relative standard deviation values of <6%. The limits of quantitation ranged from 0.1 to 1 ng/g. Enrofloxacin and ciprofloxacin were also successfully determined in enrofloxacin-incurred shrimp using this method.

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