scholarly journals Complex Activity and Sensor Potential toward Metal Ions in Environmental Water Samples of N-Phthalimide Azo-Azomethine Dyes

Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 5885
Author(s):  
Stela Georgieva ◽  
Artem Bezfamilnyi ◽  
Anton Georgiev ◽  
Marian Varbanov

Herein, the spectral and electrochemical characterizations of three different substituted N-phthalimide azo-azomethine (NAA) dyes (L) containing an o-hydroxy group and their NAA-M(II) chelates [M(II): Cu, Ni, Co, Pb] were reported by using UV–Vis and fluorescence spectroscopy and potentiometric and voltamperometric techniques. The pK value of the dyes as well as the stoichiometry and stability of the NAA-metal chelates were studied, and the stoichiometry was found to be mostly 1:2 (ML2) with high complex stability constant values. The sensor activity of N-phthalimide azo-azomethine derivatives toward pH and metal ions has been also investigated and tested for indicator application in acid–base analysis and detection of Cu(II) ions in real samples of surface river water using voltamperometric detection. The results showed that one of the ligands possesses the highest electrochemical response upon binding to copper ions and could be successfully used in the analysis of copper in water at a concentration range of the analyte from 3.7 × 10−7 to 5.0 × 10−6 mol L−1, with analytical characteristics of the method being Sr = 1.5%, LOD = 3.58 µg L−1 and LOQ =11.9 µg L−1

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1099
Author(s):  
Sheng-Chun Hung ◽  
Chih-Cheng Lu ◽  
Yu-Ting Wu

The optical characteristics of copper ion detection, such as the photometric absorbance of specific wavelengths, exhibit significant intensity change upon incident light into the aqueous solutions with different concentrations of metal ions due to the electron transition in the orbit. In this study, we developed a low-cost, small-size and fast-response photoelectric sensing prototype as an optic sensor for copper (Cu) ions detection by utilizing the principle of optical absorption. We quantified the change of optical absorbance from infra-red (IR) light emitting diodes (LEDs) upon different concentrations of copper ions and the transmitted optical signals were transferred to the corresponding output voltage through a phototransistor and circuit integrated in the photoelectric sensing system. The optic sensor for copper (Cu) ions demonstrated not only excellent specificity with other metal ions such as cadmium (Cd), nickel (Ni), iron (Fe) and chloride (Cl) ions in the same aqueous solution but also satisfactory linearity and reproducibility. The sensitivity of the preliminary sensing system for copper ions was 29 mV/ppm from 0 to 1000 ppm. In addition, significant ion-selective characteristics and anti-interference capability were also observed in the experiments by the proposed approach.


2012 ◽  
Vol 200-202 ◽  
pp. 426-432 ◽  
Author(s):  
S.A. Nabi ◽  
A.S. Raeissi ◽  
Mohammad Shahadat ◽  
Rani Bushra ◽  
Amjad Mumtaz Khan

1974 ◽  
Vol 27 (5) ◽  
pp. 955 ◽  
Author(s):  
AG MacKay ◽  
JF Boas ◽  
GJ Troup

The preparations and magnetic and spectral properties of one ytterbium and two gadolinium phthalocyanines are described and comparisons made with previous studies. The susceptibility of all three compounds followed a Curie-Weiss law, with � small, and the magnetic moments were typical for trivalent rare-earth compounds with little or no coupling between the metal ions. The e.p.r. signals observed were due to the metal ions. Structures proposed are Cl(pc)YbCl,2H2O (where pc = C32H16N8) for ytterbium, and (pc)Gd(pc)H and an associated anionic form for gadolinium. Both gadolinium materials are stable under certain solution conditions, although the anionic material tends to decompose and is difficult to obtain from solution. A polymeric form of phthalonitrile (m.p. 306�C) was isolated during purification. A simple acid-base equilibrium is proposed for the gadolinium compounds but it is complicated by the separation procedures and by the nature and purity of the solvent.


2015 ◽  
Vol 15 (1) ◽  
pp. 61-66
Author(s):  
Ranjan Nepal ◽  
Raja Ram Pradhananga

Lead oxide-graphite composite electrode for pH measurement had been fabricated with different percentage of PbO2 in the composite. The proportions of lead oxide affected the sensitivity of the electrode. The electrode composed of 50% lead oxide and 50% graphite gave reproducible result and behaved in Nernstian manner with a potential gradient of -58.8±0.3 mV per unit change in pH. Metal ions such as iron (II), iron (III) and lead (II) interfered in the measurement of pH, while silver (I), copper (II), oxidizing agents such as dichromate and permanganate do not interfere. In absence of interfering ion, the lead oxide-graphite composite electrode could be used for the measurement of pH from 2 to 11. This electrode can also be used as an indicator electrode for acid base titrations. Low cost, quick response, easy to fabricate are some of the advantages of the lead oxide-graphite composite electrode. This electrode is also found to be sensitive to Pb2+ -ions and can be used as a Pb2+-ion sensor up to 10-4M.DOI: http://dx.doi.org/10.3126/njst.v15i1.12015  Nepal Journal of Science and TechnologyVol. 15, No.1 (2014) 61-66


Micromachines ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1380
Author(s):  
Binfeng Yin ◽  
Xinhua Wan ◽  
Changcheng Qian ◽  
A. S. M. Muhtasim Fuad Sohan ◽  
Teng Zhou ◽  
...  

Metal ions in high concentrations can pollute the marine environment. Human activities and industrial pollution are the causes of Cu2+ contamination. Here, we report our discovery of an enzyme method-based microfluidic that can be used to rapidly detect Cu2+ in seawater. In this method, Cu2+ is reduced to Cu+ to inhibit horseradish peroxidase (HRP) activity, which then results in the color distortion of the reaction solution. The chip provides both naked eye and spectrophotometer modalities. Cu2+ concentrations have an ideal linear relationship, with absorbance values ranging from 3.91 nM to 256 μM. The proposed enzyme method-based microfluidic chip detects Cu2+ with a limit of detection (LOD) of 0.87 nM. Other common metal ions do not affect the operation of the chip. The successful detection of Cu2+ was achieved using three real seawater samples, verifying the ability of the chip in practical applications. Furthermore, the chip realizes the functions of two AND gates in series and has potential practical implementations in biochemical detection and biological computing.


2021 ◽  
Vol 2129 (1) ◽  
pp. 012010
Author(s):  
B Haryanto ◽  
S E Saragih ◽  
R Tambun ◽  
H Harahap ◽  
K Manik ◽  
...  

Abstract Carbon charcoal was made from rambutan rods and used as an adsorbent. A gram 70/100 mesh size of adsorbent was then used to adsorb 100 ml of copper ion solution with a 70 ppm concentration. In this investigation, the batch procedure was used without shaking (naturally). The charcoal carbon rambutan ability to remove the copper ion was measured by AAS. The percentage result was 48,135% or about 33,694 ppm. SEM and EDX instrument analysis have applied to confirm the presence of copper ions on the adsorbent surface. The copper ion was found at a concentration of 0.09 percent of the total weight. The carbon charcoal adsorbent in rambutan rods has the ability to purify the water contaminated by metal ions.


Sign in / Sign up

Export Citation Format

Share Document