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Updated: Jul 6, 2026
05:15
An Aptamer-based Sensor for Unchelated Gadolinium(III)
Published on: January 9, 2017
Extracellular gadolinium contrast agents: differences in stability
1Department of Diagnostic Imaging, Sheffield Teaching Hospitals NHS Foundation Trust, Northern General Hospital, Sheffield S5 7AU, UK. sameh.morcos@sth.nhs.uk
European Journal of Radiology
|March 18, 2008
Summary
Gadolinium contrast agents (Gd-CA) stability impacts nephrogenic systemic fibrosis risk. Stable macrocyclic Gd-CA, unlike less stable linear agents, show no associated NSF cases, highlighting safety differences.
Area of Science:
- Radiology
- Medical Imaging
- Pharmacology
Background:
- Extracellular gadolinium contrast agents (Gd-CA) are crucial for MRI.
- Gd-CA exist as linear or macrocyclic chelates, and ionic or non-ionic preparations.
- Agent structure and ionicity influence Gd-CA stability and safety.
Purpose of the Study:
- To evaluate the relationship between Gd-CA structure, stability, and nephrogenic systemic fibrosis (NSF).
- To compare the stability of different Gd-CA formulations.
- To assess the clinical implications of Gd-CA stability for patient safety.
Main Methods:
- Analysis of stability constants and kinetic measurements for various Gd-CA.
- In vivo assessment of Gd-CA stability.
- Review of clinical data regarding NSF occurrence with different Gd-CA types.
Main Results:
- Ionic-macrocyclic chelates (e.g., Gd-DOTA) are most stable; non-ionic linear chelates (e.g., gadodiamide) are least stable.
- In vivo data confirmed lower stability of non-ionic linear chelates.
- No significant stability difference was found among macrocyclic agents (ionic or non-ionic).
Conclusions:
- Gd-CA stability is a key factor in NSF pathogenesis.
- Low-stability Gd-CA may release free Gd ions, leading to tissue deposition and fibrosis.
- Exclusive use of stable macrocyclic Gd-CA is associated with no observed NSF cases.
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