Related Experiment Video
Updated: Jun 5, 2026
12:52
Iridium(III) Luminescent Probe for Detection of the Malarial Protein Biomarker Histidine Rich Protein-II
Published on: July 7, 2015
Hg(II) selective complexation by chromoionophoric calix[4]arene derivative
Mansoor Ahmed Qazi1, Imdadullah Qureshi, Shahabuddin Memon
1National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080, Pakistan.
Journal of Fluorescence
|January 12, 2011
Summary
This study explores the selective complexation of mercury(II) ions by a specific calix[4]arene derivative. The compound shows a strong preference for mercury(II) over other transition metals, forming a 1:1 complex.
Area of Science:
- Coordination Chemistry
- Supramolecular Chemistry
- Analytical Chemistry
Background:
- Calix[4]arene derivatives are known for their host-guest complexation abilities.
- Selective metal ion detection is crucial for environmental monitoring and biological studies.
- Mercury(II) poses significant environmental and health risks, necessitating sensitive detection methods.
Purpose of the Study:
- To investigate the selective complexation behavior of 5,11,17,23-tetrakis[(N,N-dimethylamino)methyl]-25,26,27,28-tetrahydroxycalix[4]arene (4) towards Hg(II).
- To evaluate the binding affinity of compound 4 for various transition metal ions.
- To determine the stoichiometry of the complex formed between compound 4 and Hg(II).
Main Methods:
- UV-visible spectroscopy to study complex formation and binding affinities.
- Fluorescence spectroscopy to assess the interaction between the calix[4]arene and metal ions.
- Job's plot analysis to determine the complex stoichiometry.
- Fourier-transform infrared (FT-IR) spectroscopy to confirm complexation.
Main Results:
- Compound 4 exhibits a pronounced selectivity for Hg(II) complexation, even in the presence of competing metal ions like Cd(II), Co(II), Cu(II), Ni(II), Pb(II), and Zn(II).
- Spectroscopic investigations confirm the formation of a stable 1:1 host-guest complex between Hg(II) and compound 4.
- FT-IR analysis provides supporting evidence for the complexation of Hg(II) by the calix[4]arene derivative.
Conclusions:
- The synthesized calix[4]arene derivative (4) demonstrates excellent selectivity and affinity for Hg(II) ions.
- The findings suggest potential applications of compound 4 in the selective detection or removal of mercury(II) from complex matrices.
- The study highlights the utility of spectroscopic techniques in characterizing metal-ligand interactions.
More Related Videos
07:54Analysis of AtHIRD11 Intrinsic Disorder and Binding Towards Metal Ions by Capillary Gel Electrophoresis and Affinity Capillary Electrophoresis
Published on: August 22, 2018
12:27Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Related Concept Videos
00:56Extraction: Advanced Methods
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is formed in...
01:19Complexation Equilibria: The Chelate Effect
In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
03:45Formation of Complex Ions
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
03:02Colors and Magnetism
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
00:43Complexometric 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...
01:09Ion-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...