scholarly journals Enhancement of stripping technique for Copper(II) detection in water sample using N,N’-bis(2-hydroxy-4-methoxyacetophenone)ethylenediamine (BME)

Author(s):  
Syaza Azhari ◽  
Rahmalan Ahamad ◽  
Farediah Ahmad

A highly sensitive, rapid, simple and selective stripping assay for the determination of trace copper(II) is proposed.  The selectivity and sensitivity of the electroanalytical process on a glassy carbon (GC) electrode were enhanced using the newly synthesized Schiff base N,N’-bis(2-hydroxy-4-methoxyacetophenone)ethylenediamine (BME). The methodology is based on the accumulation of copper(II)–BME complex onto the GC electrode, followed by electrochemical oxidation of the adsorbed species. The effect of experimental parameters such as pH, BME concentration, scan rate, accumulation time and accumulation potential on the sensitivity of copper(II) detection were investigated. Under the optimal conditions, BME has successfully enhanced the copper(II) detection using the GC electrode by nearly 95% with detection limit (LOD) of  2.6 ngL−1. The effects of interfering ions such as Cd(II), Zn(II), Fe(II), Cr(III) and Pb(II) were also investigated. The applicability of this technique was illustrated by the determination of copper(II) ion in tap water.________________________________________GRAPHICAL ABSTRACT 

2008 ◽  
Vol 3 ◽  
pp. ACI.S939 ◽  
Author(s):  
J. Rodríguez Flores ◽  
A.M. Contento Salcedo ◽  
L. Muñoz Fernández

Micellar electrokinetic chromatography (MEKC) was investigated for the simultaneous determination of letrozole, imipramine and their metabolites in human urine samples over a concentration range of therapeutic interest. Experimental parameters such as pH of the running electrolyte, sodium dodecylsulphate (SDS) concentration, borate concentration, voltage, etc were investigated. Under optimal conditions of 25 mM SDS, 15 mM borate buffer (pH 9.2), 15% 2-propanol, as background electrolyte; 28 kV and 40 °C, as voltage and cartridge temperature, respectively; resolution between the peaks was greater than 1.7. Before the determination, a solid phase extraction (SPE) procedure with a C18 cartridge was optimized. Good linearity, accuracy, precision, robustness and ruggedness were achieved and detection limits of 12.5 ng/mL for letrozole and its metabolite and 37.5 ng/mL, were obtained for imipramine and their metabolites. Real determinations of these analytes in two patient urines were carried out. Sensitivity achieved in this method is sufficient to perform kinetic studies in humans.


2016 ◽  
Vol 8 (21) ◽  
pp. 4272-4276 ◽  
Author(s):  
Cheng Chen ◽  
Xin Li ◽  
Xia Xie ◽  
Fengxia Chang ◽  
Meixian Li ◽  
...  

A CE-UV method has been developed for the simultaneous separation and sensitive determination of copper(i) and copper(ii) in cell specimens.


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Dariusz Guziejewski ◽  
Agnieszka Nosal-Wiercińska ◽  
Sławomira Skrzypek ◽  
Witold Ciesielski ◽  
Sylwia Smarzewska

The aim of the research was the use of square wave adsorptive stripping voltammetry (SWAdSV) in conjunction with a hanging mercury drop electrode (HMDE) for the determination of nitrothal-isopropyl. It was found that optimal SW technique parameters were frequency, 200 Hz; amplitude, 50 mV; and step potential, 5 mV. Accumulation time and potential were studied to select the optimal conditions in adsorptive stripping voltammetry: 45 s at 0.0 V, respectively. The calibration curve (SWSV) was linear in the nitrothal-isopropyl concentration range from 2.0 × 10−7 to 2.0 × 10−6 mol L−1 with detection limit of 3.46 × 10−8 mol L−1. The repeatability of the method was determined at a nitrothal-isopropyl concentration level equal to 6.0 × 10−7 mol L−1 and expressed as RSD = 5.5% (n=6). The proposed method was successfully validated by studying the recovery of nitrothal-isopropyl in spiked environmental samples.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
F. M. Alshareef ◽  
M. I. Orif ◽  
E. A. Al-Harbi ◽  
M. S. El-Shahawi

The current strategy reports a highly sensitive and selective square wave-cathodic stripping voltammetric protocol for malathion determination. The established method was based on the controlled adsorptive accumulation of malathion in the presence of Cu2+ ions in an aqueous solution of pH 2 onto the hanging mercury dropping electrode (HMDE) and measuring the resulting cathodic peak current of the adsorbed species at −0.42 V versus Ag/AgCl electrode. The low limits of detection (LOD) and quantification (LOQ) of malathion of the assay were estimated to be 3.1 × 10−10 and 1.03 × 10−9 M with a linear dynamic range of 1.03×10−9 – 2.0 × 10−7 M, respectively. The method was satisfactorily applied and validated for malathion determination in environmental samples. The experimental Student texp and Fexp values did not exceed the tabulated ttab (2.78) and Ftab (6.39) at 95% (P = 0.05) confidence (n = 5), confirming the precision and independence on the matrix. The developed sensing platform for the detection of malathion shows superior performance to conventional electrochemical methods. The proposed sensor offered simple, economical, reproducible, and applicable approach for the determination of malathion in environmental samples.


2008 ◽  
Vol 91 (3) ◽  
pp. 542-550 ◽  
Author(s):  
Nahed El-Enany

Abstract A rapid, simple, and highly sensitive second derivative synchronous fluorometric method has been developed for the simultaneous determination of metoclopramide (MT) and pyridoxine (PY) in a binary mixture. The method is based on measurement of the native fluorescence of these drugs at = 80 nm in methanol. The different experimental parameters affecting the native fluorescence of the drugs were carefully studied and optimized. The fluorescence-concentration plots were rectilinear over the ranges of 0.020.4 and 0.12 g/mL for MT and PY, respectively. The limits of detection were 0.003 and 0.007 g/mL and the limits of quantification were 0.008 and 0.02 g/mL for MT and PY, respectively. The proposed method was successfully applied to the determination of MT and PY in synthetic mixtures and in commercial syrup. The results were in good agreement with those obtained with a reported method. The high sensitivity attained by the proposed method allowed the determination of MT in spiked and real human plasma samples. The mean percent recoveries of MT from spiked and real human plasma (n = 3) were 93.72 3.15 and 89.72 2.19, respectively.


2018 ◽  
Vol 42 (4) ◽  
pp. 2590-2604 ◽  
Author(s):  
Seyed Alireza Shahamirifard ◽  
Mehrorang Ghaedi

A selective, accurate and highly sensitive optical chemical sensor (optode) for the simultaneous determination of copper(ii) and cobalt(ii) without any prior separation or purification ion sensing was developed.


2013 ◽  
Vol 295-298 ◽  
pp. 622-625
Author(s):  
Xin Yi Wang ◽  
Wen Dong ◽  
Wei Li Xue ◽  
Shu Hao Wang

A highly sensitive direct competitive fluorescence immunoassay (FIA) was developed for the determination of diethylstilbestrol (DES), based on the antibody coating format using biotin-streptavidin amplification system. In the assay, DES competed with biotinylated goat anti-rabbit IgG for the immobilized antibody, then the streptavidin-FITC was added to link to the biotinylated goat anti-rabbit IgG as a tracer. Under optimal conditions, the assay provided a wide analytical range of 0.001-10000 ng/mL with a detection limit of 2.91×10-4ng/mL (R2=0.9943). This method was then applied to the determination of DES in chicken with satisfactory results


Sign in / Sign up

Export Citation Format

Share Document