Related Experiment Video
Updated: Dec 16, 2025

IridiumIII Luminescent Probe for Detection of the Malarial Protein Biomarker Histidine Rich Protein-II
Published on: July 7, 2015
Dye/metal ion-based chemosensing ensemble towards l-histidine and l-lysine determination in water via different
Hossein Tavallali1, Omid Espergham1, Gohar Deilamy-Rad1
1Department of Chemistry, Payame Noor University, 19395-4697, Tehran, Islamic Republic of Iran.
Abstract:
In this study, a novel simple type of label-free, ultra-sensitive, and highly selective UV-Vis absorption and naked-eye detection of histidine (His) and lysine (Lys) using a dye/metal ion ensemble is developed. The outcoming high sensitivity and selectivity for histidine and lysine were attained by changing the metal ions. The indicator is released due to its displacement from the murexide (Mure)/Cu2+ complex by histidine and the change in absorbance may be due to the further complexation of lysine with the additional coordination sites present in the zinc atom of Mure/Zn2+ complex. The label-free chemosensor provided sensitive and selective detection of l-histidine and l-lysine with detection limits of 9.1 and 9.4 nmol L-1, respectively. The protocol especially offers high selectivity for the determination of His and Lys among amino acids found in human urine samples. Furthermore, INHIBIT and NAND molecular logic gates were obtained using chemical inputs and UV-Vis absorbance signal output.
More Related Videos
Related Concept Videos
Complexometric Titration: Ligands
Effects of EDTA on End-Point Detection Methods
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a...
Complexometric Titration: Overview
High-Performance Liquid Chromatography: Types of Detectors
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Labeling DNA Probes
Radioisotopes, fluorophores, or small molecule binding partners like biotin or digoxigenin, are the most widely used reporter tags for labeling DNA probes. These labels can be attached to the probe DNA molecule via...

