scholarly journals Removal of copper from Octopus vulgaris haemocyanin. Preparation of the half-apo and apo derivatives

1984 ◽  
Vol 221 (3) ◽  
pp. 911-914 ◽  
Author(s):  
M Beltramini ◽  
F Ricchelli ◽  
A Piazzesi ◽  
A Barel ◽  
B Salvato

The two copper ions bound in the active site of Octopus vulgaris haemocyanin can be removed by cyanide. The two metal ions react with the ligand sequentially. In this paper the preparation of Octopus half-apo-haemocyanin, containing at the active site a single copper ion, is described. Moreover, the conditions to obtain Octopus apo-haemocyanin, containing less than 3% of copper still bound, are given.

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.


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.


BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 8369-8383
Author(s):  
Qi An ◽  
Mei-Ling Han ◽  
Lu-Sen Bian ◽  
Zhi-Chao Han ◽  
Ning Han ◽  
...  

Submerged fermentation with single or mixed metal ions as inducers was used for laccase production from white rot fungi. Mixed metal ions were used for the first time as inducers for Pleurotus ostreatus and Flammulina velutipes to enhance laccase activity. The maximum laccase activity from P. ostreatus in basal media, metal ion media 1 containing copper ion, metal ion media 2 containing manganese ion, metal ion media 3 containing manganese and copper ions, metal ion media 4 containing ferrous ion, metal ion media 5 containing manganese and ferrous ions, metal ion media 6 containing ferrous and copper ions, and metal ion media 7 containing manganese, copper and ferrous ions were, respectively, approximately 21.5-fold, 4.7-fold, 14.9-fold, 16.9-fold, 4.0-fold, 11.0-fold, 12.7-fold, and 24.8-fold higher than that from F. velutipes. The combination of copper and manganese ions as inducers was superior to that of a single copper ion or manganese ion. The maximum laccase activity of P. ostreatus rose in media containing manganese and copper ions. The single copper ion as the inducer for enhancing laccase activity was more suitable for F. velutipes. These findings are helpful in selecting the appropriate single metal ion or mixed metal ions to enhance laccase activity.


1997 ◽  
Vol 492 ◽  
Author(s):  
Richard J. Blint

AbstractCopper ions exchanged into the zeolite, ZSM-5, are known to catalyze the reduction of NO to N2 in the oxidizing environment of lean automotive exhaust, but do require trace hydrocarbons. The interface of this catalyst provides a locally reducing environment even when the surrounding exhaust has molecular oxygen concentrations as high as 10%. The mechanism of this reduction is still unclear; however, structure calculations of the active sites and dynamics simulations of species diffusion within the zeolite pores provide insight into the mechanism of reduction. One active site is proposed to be Cu++ ionically bound to a bridge oxygen in a nonsymmetric site within a zeolitic pore. Another proposed site has the copper ion centrally (symmetrically) bound within a six member zeolitic ring. Evidence suggests that the copper ions cycle between Cu++ and Cu+ during the reduction of NO to N2. The nonsymmetric copper ions are shown here to be hydrated ions attached to the Brønsted acid sites in the zeolite. The calculations here show a four member, first hydration shell for Cu++ and a first shell of 2–3 oxygens for the Cu+ ion. An examination of the pore size in ZSM-5 indicates sufficient room for a first and second hydration shell for most of the possible acid sites. The conclusion that the copper ions are typically hydrated suggests that the catalytic mechanism may have much in common with homogeneous catalysis which is sometimes termed heterogenized homogeneous catalysis.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Y. Shimizu ◽  
I. Hirasawa

Reactive crystallization designed to separate nickel or copper ion from effluents has been advanced for applying to actual industrial wastewater containing impurities. In the primary reaction of this method, metal sulfate solution reacts with sodium carbonate solution in a semibatch crystallizer. In the present study, during the process of nickel or copper ions incorporation, inhibitory effect on seed growth of impurities, like cobalt, manganese, zinc, and borate and phosphate ions, was investigated. Through the 8-hour reactive crystallization, obtained particles’ characters and metals removal efficient were examined. Considering analyses data on metal component ratio in produced crystals, metal ions initial uptake rate was found to be different by the kind of seeds and impurities. And the centrifugation was performed against obtained crystals aimed for examining target metal purity improvement. The results indicated that copper components can incorporate and remove other metal ions easily. In addition, when the anions are used as impurities, depending on the kind of anions, the effect of damaging the surface of seeds or producing many fine particles has been confirmed.


Micromachines ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1468
Author(s):  
Yuekun Wang ◽  
Yuhao Xu ◽  
Jinhua Jiang ◽  
Yang Li ◽  
Jianhua Tong ◽  
...  

In this study, an ultramicro interdigital electrode array chip (UIEA) was designed and fabricated by using Micro-Electro-Mechanical systems (MEMS) technology, and a portable detection system, using the chip for determination of heavy-metal ions in water, was developed. The working electrode of the UIEA was modified with gold nanoparticles by electrodeposition. The detection sensitivity of the UIEA chip for copper ions was 0.0138 μA·L·μg−1, with the linear range of 0–400 μg/L and the detection limit of 18.89 μg/L (3σ), which was better than that of the compared columnar glassy carbon electrode. The results of the interference experiment verified that the UIEA chip has a certain anti-interference ability against common heavy-metal ions in water, such as Pb2+, Zn2+, and Mg2+ ions. The standard addition method was used to investigate the performance of the developed s ystem for copper ion determination in real water. The recovery range from 87.5% to 94.7% was achieved.


2009 ◽  
Vol 6 (1) ◽  
pp. 161-168 ◽  
Author(s):  
Tariq S. Najim ◽  
Nazik J. Elais ◽  
Alya A. Dawood

In this study, pine fruit was used as solid adsorbent for removal of ferrous and copper ions from aqueous solutions through batch equilibrium technique. The influence of contact time, pH of the solution and initial concentration of metal ions on adsorbed amount of metal ions were investigated. 90 minutes of adsorption time was found sufficient to reach equilibrium for ferrous ion and 120 minutes for copper ion. Adsorption of metal ions were pH dependent and the results indicate the optimum pH for the removal of Fe+2was found to be 5.0 and that of Cu+2was 7.0, the highest adsorption capacity was found to be 4.8 and 14.1 mg of metal ion per gram of adsorbent at initial concentration of 22.22 mg/L and 57.6 mg/L of ferrous and copper ions respectively and would be higher with higher initial concentration. Ferrous ion was removed by 96.3 - 97.3% and copper ion by 94.1-96% along the whole range of initial concentrations. Isotherm studies showed that the data were best fitted to the Freundlich isotherm model. The kinetic data corresponded well with the pseudo-second order equation, suggesting that the adsorption process is presumably a chemisorption.


2016 ◽  
Vol 45 (18) ◽  
pp. 7665-7671 ◽  
Author(s):  
Shanshan Guo ◽  
Shousi Lu ◽  
Pingxiang Xu ◽  
Yi Ma ◽  
Liang Zhao ◽  
...  

We report a biomimetic method to synthesize needle-like calcium phosphate (CaP) using carbon dots (CDs) and sodium carboxymethylcellulose as dual templates. The CaP/CDs were capable of cell labeling and selective detection of copper ions in drinking water.


2012 ◽  
Vol 24 (05) ◽  
pp. 453-459 ◽  
Author(s):  
Shenhsiung Lin ◽  
Chia-Chen Chang ◽  
Chii-Wann Lin

Heavy metals greatly influence animal physiology, even at small doses. Among these metals, the copper ion is of great concern due to its effects on humans and wide applications in industry. Compared to atomic absorption spectroscopy and inductively coupled plasma-mass spectrometry, which destroy the samples that are analyzed, optical techniques do not decompose the analyte and have become a popular field of recent research. In this paper, we combined a novel optical detector that did not require sample-labeling, called surface plasmon resonance (SPR), with chitosan to detect copper ions by modifying the functional groups of chitosan through pH modification. Compared to other optical detectors, the SPR system was relatively fast and involved fewer experimental confounding factors. The three-dimensional structure of chitosan was used to obtain lower detection limits. Moreover, modification of the chitosan functional groups resulted in efficient regeneration by controlling the pH. A detection limit of 0.1 μM was obtained (linear range: 0.5–10 μM, R2 = 0.976), and the specificity was certified by comparing the copper ion with six other ions. Additionally, we successfully regenerated the SPR chips by modifying the functional groups. In conclusion, the chitosan–SPR system detected copper ions with improved detection limits using a quick and simple regeneration method.


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