A fluoride selective water-soluble anion receptor based on a 1,2-phenylenediacetic acid and calcium ion dimer

2019 ◽  
Vol 43 (34) ◽  
pp. 13690-13695
Author(s):  
Dae Hyup Sohn ◽  
Nayeon Kim ◽  
Soonmin Jang ◽  
Jongmin Kang
Keyword(s):  
Calcium Ions ◽  
Calcium Ion ◽  
Water Soluble ◽  
Anion Receptor ◽  
Fluoride Ions

The dimeric receptor 1 from 1,2-phenylenediacetic acid and calcium ions recognized fluoride ions almost exclusively in 100% water.

Lowest aqueous picomolar fluoride ions and in vivo aluminum toxicity detection by an aluminum(iii) binding chemosensor

2021 ◽  
Author(s):  
Monojit Das ◽  
Debdeep Maity ◽  
Tusar Kanta Acharya ◽  
Sudip Sau ◽  
Chandan Giri ◽  
...  
Keyword(s):  
Detection Limit ◽  
Aluminum Toxicity ◽  
Biological Systems ◽  
Water Soluble ◽  
Fluoride Ions ◽  
Toxicity Effect

A water-soluble PET-based chemosensor is developed which can detect Al(iii) and F− ions up to nano- and picomolar (lowest detection so far) detection limit, respectively, also utilized to establish aluminum-toxicity effect in biological systems.

Efficient sensing of fluoride ions in water using a novel water soluble self-assembled supramolecular sensor based on pillar[5]arene

RSC Advances ◽  
2016 ◽  
Vol 6 (113) ◽  
pp. 111928-111933 ◽  
Author(s):  
Qi Lin ◽  
Feng Zheng ◽  
Lu Liu ◽  
Peng-Peng Mao ◽  
You-Ming Zhang ◽  
...  
Keyword(s):  
High Selectivity ◽  
Water Soluble ◽  
Fluoride Ions ◽  
Competitive Coordination ◽  
Self Assembled

By rationally introducing competitive coordination, the supramolecular sensors could reversibly sense Fe3+ and F− in water with high selectivity and sensitivity.

scholarly journals Magneto-sensitive hybrid nanocomposites of water-soluble sodium alginate cross-linked with calcium ions and maghemite

2018 ◽  
Vol 12 (5) ◽  
pp. 452-461 ◽  
Author(s):  
V. V. Spiridonov ◽  
I. G. Panova ◽  
L. A. Makarova ◽  
S. B. Zezin ◽  
A. A. Novakova ◽  
...  
Keyword(s):  
Sodium Alginate ◽  
Calcium Ions ◽  
Water Soluble ◽  
Hybrid Nanocomposites

scholarly journals THE EFFECT OF LACTIC ACID AND ARTIFICIAL SALIVA SOLUTION IMMERSION TO THE RELEASE OF CALCIUM IONS ON BIOACTIVE RESIN

2021 ◽  
Vol 6 (2) ◽  
pp. 190
Author(s):  
Dewi Puspitasari ◽  
Nurah Tajjalia ◽  
Diana Wibowo ◽  
Agung Satria Wardhana
Keyword(s):  
Lactic Acid ◽  
Acid Solution ◽  
Calcium Ions ◽  
Calcium Ion ◽  
Artificial Saliva ◽  
Distilled Water ◽  
Acid Condition ◽  
Ion Release ◽  
Lactic Acid Solution ◽  
Solution Increase

Background: Bioactive resin can release calcium ions when contact with solution media, even in acid condition. In the oral cavity, pH may change into acid condition due to the metabolic results of Streptococcus mutans. The bacteria metabolize carbohydrates into organic acids, one of which is lactic acid. Purpose: Analyze the effect of lactic acid solution and artificial saliva on the number of the release of calcium ions of bioactive resin. Methods: Forty-two specimens (diameter 15 mm x thickness 1 mm; n= 7/group fabricated with Activa™ Bioactive Restorative (Pulpdent). The specimens that meet the criteria were divided into 6 groups. The specimen was immersed for 1 and 7 days in the incubator at 37oC. The number of calcium ion release is measured using titration method. Results: Two Way Anova test and Post Hoc Bonferonni test showed there were significant differences among all group for lactic acid 1 day (4.040 ± 0.360) µg, artificial saliva 1 day (0.640 ± 0.338) µg, distilled water 1 day (1.040 ± 0.504) µg, lactic acid 7 days (5.400 ± 0.312), artificial saliva 7 days (1.640 ± 0.215) µg, distilled water 7 days (3.520± 0.356 µg). Conclusion: There was an influence of lactic acid and artificial saliva on the number of calcium ion releases of bioactive resin. Immersion of bioactive resin in the lactic acid solution increase the calcium ion releases and artificial saliva decrease the calcium ion release compared to distilled water. Keywords: artificial saliva, bioactive resin, calcium ion release, lactic acid

HIGH AFFINITY CALCIUM BINDING TO DOMAINES OF PROTEIN C THAT ARE HOMOLOGUS TO THE EPIDERMAL GROWTH FACTOR

1987 ◽  
Author(s):  
A KÖhlin ◽  
J Stenflo
Keyword(s):  
Calcium Ions ◽  
Calcium Ion ◽  
Calcium Binding ◽  
Plasma Proteins ◽  
Metal Ion ◽  
Protein C ◽  
Protein S ◽  
Protein Z ◽  
High Affinity ◽  
Epidermal Growth

In addition to γ-carboxyglutamic acid (Gla)-dependent calcium binding all of the vitamin K-dependent plasma proteins, except prothrombin, have one or two high affinity calcium binding sites that do not require the Gla residues. A common denominator among these proteins (factors IX, X, protein C, protein Z and protein S) is that they have domaines that are homologus to the epidermal growth factor (EGF) precursor. In factors VII,IX,X, protein C and in protein Z the aminoterminal of two EGF homology regions contain one residue of β-hydroxyaspartic acid (Hya) whereas in protein S the aminoterminal EGF homology region contains Hya and the three following contain one β-hydroxyasparagine residue each.In an attempt to elucidate the role of the EGF homology regions in the Gla independent calcium binding we have isolated a tryptic fragment (residue 44-138) from the light chain of human protein C. The fragment was isolated using a monoclonal antibody that recognizes a calcium ion stabilized epitope that is expressed both in intact protein C and in protein C lacking the Gla domaine.The antibody bound the isolated EGF homology region in the presence of calcium ions but not in EDTA containing buffer. A calcium ion titration showed half maximal binding at approximately 200 μM Ca2+. The metal ion induced conformational change in the isolated fragment was also studied with affinity purified rabbit antibodies against Gla domainless protein C. Antibodies that bound in the presence of calcium ions and that could be eluted with EDTA recognized the metal ion induced conformational change in the isolated EGF homology domain. Our results suggest that one or both of the EGF homology regions are involved in the Gla-independent high affinity calcium binding in the vitamin K-dependent plasma proteins.

scholarly journals Probing the Role of Divalent Metal Ions in a Bacterial Psychrophilic Metalloprotease: Binding Studies of an Enzyme in the Crystalline State by X-Ray Crystallography

2003 ◽  
Vol 185 (14) ◽  
pp. 4195-4203 ◽  
Author(s):  
Stephanie Ravaud ◽  
Patrice Gouet ◽  
Richard Haser ◽  
Nushin Aghajari
Keyword(s):  
Metal Ions ◽  
Calcium Ions ◽  
Calcium Ion ◽  
Crystalline State ◽  
Zinc Ion ◽  
Binding Studies ◽  
X Ray ◽  
X Ray Crystallography ◽  
Catalytic Zinc

ABSTRACT The psychrophilic alkaline metalloprotease (PAP) produced by a Pseudomonas bacterium isolated in Antarctica belongs to the clan of metzincins, for which a zinc ion is essential for catalytic activity. Binding studies in the crystalline state have been performed by X-ray crystallography in order to improve the understanding of the role of the zinc and calcium ions bound to this protease. Cocrystallization and soaking experiments with EDTA in a concentration range from 1 to 85 mM have resulted in five three-dimensional structures with a distinct number of metal ions occupying the ion-binding sites. Evolution of the structural changes observed in the vicinity of each cation-binding site has been studied as a function of the concentration of EDTA, as well as of time, in the presence of the chelator. Among others, we have found that the catalytic zinc ion was the first ion to be chelated, ahead of a weakly bound calcium ion (Ca 700) exclusive to the psychrophilic enzyme. Upon removal of the catalytic zinc ion, the side chains of the active-site residues His-173, His-179 and Tyr-209 shifted ∼4, 1.0, and 1.6 Å, respectively. Our studies confirm and also explain the sensitivity of PAP toward moderate EDTA concentrations and propose distinct roles for the calcium ions. A new crystal form of native PAP validates our previous predictions regarding the adaptation of this enzyme to cold environments as well as the proteolytic domain calcium ion being exclusive for PAP independent of crystallization conditions.

Electrochemical Properties of Multi-Wall Carbon Nanotubes as a Novel Negative Electrode for Calcium Secondary Batteries

2016 ◽  
Vol 859 ◽  
pp. 75-78
Author(s):  
Chang Hee Lee ◽  
Chang Su Kim ◽  
Yun Taek Jeong ◽  
Jun Hwan Kim ◽  
Soon Ki Jeong ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Electrochemical Performance ◽  
Calcium Ions ◽  
Calcium Ion ◽  
Ethylene Carbonate ◽  
Negative Electrode ◽  
X Ray Diffraction ◽  
X Ray ◽  
Multi Wall Carbon Nanotubes ◽  
Discharge Capacities

We investigated the electrochemical behavior and properties of multi-wall carbon nanotubes (MWCNTs) as a novel negative electrode for calcium ion batteries during charging and discharging. The second charge and discharge capacities were ~63 and ~43 mAh g–1 in propylene carbonate-based electrolyte and ~86 and ~60 mAh g–1 in ethylene carbonate-based electrolyte, respectively. X-ray diffraction analysis results showed that the inter-layer distance of the MWCNTs was increased after charging, indicating that calcium ions were intercalated into the MWCNT graphitic sheets during the charging. The electrochemical performance of the MWCNT electrode was improved by using ball milling to introduce defects.

Binding of calcium ions to bovine αsl-casein and precipitability of the protein–calcium ion complexes

1980 ◽  
Vol 47 (1) ◽  
pp. 113-122 ◽  
Author(s):  
Douglas G. Dalgleish ◽  
Thomas G. Parker
Keyword(s):  
Ionic Strength ◽  
Calcium Ions ◽  
Calcium Ion ◽  
Calcium Binding ◽  
Calcium Concentration ◽  
Binding Constants ◽  
Substitution Effects ◽  
Binding Isotherms ◽  
Decreasing Ph ◽  
Increasing Temperature

SummaryBinding isotherms for the calcium ion–αsl-casein system have been measured, as functions of ionic strength, temperature, and pH, and the isotherms have been analysed in terms of binding constants modified by substitution effects. The results demonstrate that the strength of binding is increased with increasing temperature and decreased by increasing ionic strength or decreasing pH, all of which may be explained semi-quantitatively. Parallel studies on the precipitability of the αsl-casein–Ca2+ complexes showed that there is considerable variation in the extent of calcium binding required to initiate precipitation of the protein, and in the calcium concentration necessary to achieve the required extent of ligand binding.

scholarly journals ADENOSINE TRIPHOSPHATE-LINKED CONCENTRATION OF CALCIUM IONS IN A PARTICULATE FRACTION OF RABBIT MUSCLE

1962 ◽  
Vol 14 (3) ◽  
pp. 389-400 ◽  
Author(s):  
Setsuro Ebashi ◽  
Fritz Lipmann
Keyword(s):  
Skeletal Muscle ◽  
Endoplasmic Reticulum ◽  
Electron Micrographs ◽  
Calcium Ions ◽  
Calcium Ion ◽  
Membrane Fraction ◽  
Ion Concentration ◽  
Rabbit Muscle ◽  
Differential Centrifugation ◽  
Calcium Ion Concentration

ATPase and ATP-dependent calcium ion concentration was studied with a membrane fraction isolated from homogenized rabbit skeletal muscle by differential centrifugation. Electron micrographs of the fraction indicate that it consists mainly of resealed tubules and vesicles of the endoplasmic reticulum. The up-to-1400-fold concentration of calcium in this fraction might be explained by proposing the existence of an energy-requiring system for the transport of calcium ions into the tubules or vesicles.

scholarly journals Calcium ions and cell fusion. Effects of chemical fusogens on the permeability of erythrocytes to calcium and other ions

1979 ◽  
Vol 182 (2) ◽  
pp. 555-563 ◽  
Author(s):  
A M J Blow ◽  
G M Botham ◽  
J A Lucy
Keyword(s):  
Cell Fusion ◽  
Calcium Ions ◽  
Biological Membranes ◽  
Human Erythrocytes ◽  
Water Soluble ◽  
Chemically Induced

1. Fusogenic and non-fusogenic chemicals were tesetd for their ability to allow 45Ca2+ and 3H2O to enter hen and human erythrocytes. 2. The ratio of 45Ca2+/3H2O in treated cells to that in untreated cells is referred to as the entry ratio. 3. Within 1 min at 37 degrees C both water-soluble and lipid-soluble fusogens increased the value of the entry ratio, which reached maximum values in 5–10 min. 4. Values of the entry ratio in the range of 4–12 were found under conditions that led to cell fusion. 5. Closely related but non-fusogenic chemicals did not significantly alter the entry ratio. 6. The entry ratios for 86Rb+, 22Na+ and 35SO42- were also significantly increased by both lipid-soluble and water-soluble fusogens, though the increases were not as large as those for 45Ca2+. 7. It is suggested that fusogenic compounds increase the permeability of biological membranes to ions, and that an increase in the concentration of intracellular Ca2+ initiates or facilitates events that lead to the chemically induced fusion of erythrocytes.

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