Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Ion-Exchange Chromatography

Ion-Exchange Chromatography

Ion-exchange chromatography, or IEC, is a technique for separating ions based on their affinity for the stationary phase. The stationary phase is a cross-linked polymer resin with covalently attached ionic functional groups. The functional groups can be either positively charged (cation exchangers) or negatively charged (anion exchangers). A cation exchanger consists of a polymeric anion and active cations, while an anion exchanger is a polymeric cation with active anions. The choice of...

Qualitative Analysis

Qualitative Analysis

For solutions containing mixtures of different cations, the identity of each cation can be determined by qualitative analysis. This technique involves a series of selective precipitations with different chemical reagents, each reaction producing a characteristic precipitate for a specific group of cations. Metal ions within a group are further separated by varying the pH, heating the mixture to redissolve a precipitate, or adding other reagents to form complex ions.
For instance, group IV...

Complexometric Titration: Ligands

Complexometric Titration: Ligands

Different monodentate and polydentate ligands are used as complexing agents in complexometric titration reactions. The formation of complexes by mono- and bidentate ligands involves two or more intermediate steps, limiting their use as complexing agents. In comparison, polydentate ligands can form complexes with metal ions in a single-step process, facilitating sharper end points. This means polydentate ligands, such as amino carboxylic acid derivatives, are most commonly employed in...

Complexometric EDTA Titration Curves

Complexometric EDTA Titration Curves

EDTA titration curves determine the free metal ion concentration. The titration curve represents the change in concentration of free metal ions (p function) as a function of the volume of EDTA added. This curve consists of three regions: before, at, and after equivalence points. Excess free metal ions are present before the equivalence point. Equal concentrations of metal ions and EDTA are present at the equivalence point. After the equivalence point, excess EDTA exists. This means slight...

Capillary Electrophoresis: Applications

Capillary Electrophoresis: Applications

Capillary electrophoretic separations offer various modes, each with unique applications. These modes include capillary zone electrophoresis, capillary gel electrophoresis, capillary array electrophoresis, capillary isoelectric focusing, capillary isotachophoresis, micellar electrokinetic chromatography, and capillary electrochromatography.
Capillary zone electrophoresis (CZE) separates ionic components based on their electrophoretic mobility. It has been used to separate proteins, amino acids,...

Complexometric Titration: Overview

Complexometric Titration: Overview

Complexometric titration involves the formation of a complex by reacting a metal ion with one or more ligands. A visual indicator often detects the end point of a complexometric titration. It is added to the metal solution before the titration, forming a stable metal–indicator complex and imparting color to the solution. As the titration approaches the equivalence point, the excess of the added ligand displaces the indicator from the metal–indicator complex, releasing the free indicator. The...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Letter: Potential hazards of HClO4 in heated systems where esters are involved.

Journal of the American Oil Chemists' Society·1974

Same author

Macro and semimicro determination of inorganic bromide by cerium(IV) oxidimetry.

Talanta·1966

See all related articles

Search research articles

Related Experiment Video

Updated: Jun 28, 2026

Purification of Native Complexes for Structural Study Using a Tandem Affinity Tag Method

Purification of Native Complexes for Structural Study Using a Tandem Affinity Tag Method

Published on: July 27, 2016

Calcium complexes determined by polarography.

¹Procter & Gamble Company, 6071 Center Hill Road, Cincinnati, Ohio 45224, U.S.A.

|November 1, 1980

Summary

This summary is machine-generated.

A new d.c. polarographic method accurately measures calcium ion concentrations in solutions. This technique also identifies distinct calcium complexes with common sequestrants like EDTA, NTA, and TP.

More Related Videos

Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone

Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone

Published on: February 23, 2017

Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry

Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry

Published on: October 28, 2014

Related Experiment Videos

Last Updated: Jun 28, 2026

Purification of Native Complexes for Structural Study Using a Tandem Affinity Tag Method

Purification of Native Complexes for Structural Study Using a Tandem Affinity Tag Method

Published on: July 27, 2016

Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone

Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone

Published on: February 23, 2017

Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry

Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry

Published on: October 28, 2014

Area of Science:

Analytical Chemistry
Electrochemistry

Background:

Accurate quantification of calcium ions is crucial in various scientific fields.
Understanding calcium complexation with sequestrants informs environmental and biological studies.

Purpose of the Study:

To develop a novel d.c. polarographic technique for measuring calcium ion concentrations.
To investigate the formation and characteristics of calcium complexes with ethylenediaminetetra-acetic acid (EDTA), nitrilotriacetic acid (NTA), and tripolyphosphate (TP).

Main Methods:

Utilized a d.c. polarographic technique with a dropping mercury electrode.
Applied a potential scan rate of 25 mV/sec for calcium analysis in tetrabutylammonium hydroxide.
Analyzed peak height versus concentration and mole ratio plots to identify calcium species.

Main Results:

Established a linear relationship between the square root of peak height and calcium concentration (0.1-1.0 x 10(-3)M).
Identified distinct calcium complexes: CaEDTA, Ca(3)(NTA)(2), Ca(2)(TP)(3), and Ca(3)TP.
Observed complex formation at high pH, consistent with experimental conditions.

Conclusions:

The developed d.c. polarographic method provides a reliable way to quantify calcium ions.
The study successfully characterized various calcium-sequestrant complexes, offering insights into their stability and interactions.