Spectroscopic studies of amphotericin B-Cu²+ complexes
Mariusz Gagoś1, Grzegorz Czernel, Daniel M Kamiński
1Department of Biophysics, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland. mariusz.gagos@up.lublin.pl
Summary
This study explores amphotericin B (AmB)-Cu(2+) complexes, revealing that copper ions disaggregate AmB at physiological pH. These findings on AmB-Cu(2+) interactions may have significant medical implications.
Area of Science:
- Biochemistry
- Medicinal Chemistry
- Spectroscopy
Background:
- Amphotericin B (AmB) is a vital antifungal agent.
- Understanding its interaction with metal ions like copper (Cu2+) is crucial for potential therapeutic applications.
Purpose of the Study:
- To investigate the formation and characteristics of amphotericin B-copper (AmB-Cu2+) complexes in aqueous solutions.
- To determine the influence of pH on these complex formations and AmB molecular organization.
Main Methods:
- Utilized electronic absorption, circular dichroism (CD), Raman, and FTIR spectroscopies.
- Analyzed solutions with varying concentrations of AmB and Cu2+ ions across different pH levels.
Main Results:
- Identified the formation of AmB-Cu2+ complexes with 2:1 and 1:1 stoichiometry.
- Observed significant disaggregation of AmB molecular structure at physiological pH upon complex formation.
- Spectroscopic data confirmed structural changes in AmB due to Cu2+ interaction.
Conclusions:
- Amphotericin B-copper (AmB-Cu2+) complex formation alters AmB's molecular organization, notably causing disaggregation at physiological pH.
- These pH-dependent interactions and structural changes hold potential significance for the medical application of AmB.
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