Related Experiment Video
Updated: Apr 14, 2026

A Technical Guide for Performing Spectroscopic Measurements on Metal-Organic Frameworks
Published on: April 28, 2023
[Studies on the interaction between malanin and metal ions by fluorescence spectra methods]
Abstract:
A novel protein with anti-tumor activities named malanin was isolated and purified from an endemic plant in Yunnan and Guangxi provinces. Effects of copper ion, silver ion and calcium ion on malanin and apo-malanin fluorescence spectra were studied. The results showed that copper ion leads to obvious statistic quenching of malanin and apo-malanin fluorescence. The dissociation constant of them from malanin and apo-malanin were about 2.37 X 10(-4) and 2.66 X 10(-4) mol · L(-1), respectively. The silver ion did not have quenching action on malanin fluorescence, but it had statistic quenching effect on apo-malanin fluorescence, and its dissociation constant was 2.37 X 10(-4) mol · L(-1). Calcium ion did not have quenching action on malanin and apo-malanin fluorescence. It plays an important role in keeping malanin natural conformation.
More Related Videos
Related Concept Videos
Colors and Magnetism
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...
Variables Affecting Phosphorescence and Fluorescence
Complexometric Titration: Overview
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...
Interaction of EM Radiation with Matter: Spectroscopy
Photoluminescence: Applications

