Manganese Chelate MRI Contrast Agent Kinetic Stability
Solution Overview
Problem
Current manganese (II) chelate compounds for MRI applications lack sufficient kinetic stability and transmetallation inertness, leading to potential toxicity and reduced effectiveness as contrast agents compared to gadolinium-based chelates.
Innovation Solution
Development of a manganese (II) chelate compound with specific structural modifications, including hydroxy groups and a non-coordinating amide linker, which enhances kinetic stability and resist dissociation in the presence of competing metal ions, thereby improving its retention and performance as an MRI contrast agent.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If manganese (II) chelate compounds are used as MRI contrast agents, then they offer an alternative to gadolinium-based agents, but they lack sufficient kinetic stability and transmetallation inertness leading to potential toxicity
Solution Approach 1:
The patent modifies the chelate structure by changing parameters such as adding hydroxy groups at specific positions (R1 = hydroxyalkyl), adjusting the linker structure (L = -(CH2)m-CO-NH-C1-6 hydroxyalkyl where m = 2-5), and optimizing the number of hydroxy groups (at least two hydroxy groups required). These parameter changes enhance the kinetic stability and transmetallation inertness of the manganese (II) chelate, preventing manganese ion release and associated toxicity while maintaining MRI contrast agent functionality.
2Reliability
If the chelate structure is modified to improve kinetic stability, then transmetallation inertness is enhanced, but the structural complexity increases
Solution Approach 1:
The patent applies local quality by introducing specific functional groups (hydroxy groups) at particular positions (R1, R2, R3, R4) of the chelate structure rather than uniformly modifying the entire molecule. The hydroxyalkyl groups are strategically placed on the aromatic rings and linker, providing localized enhancement of kinetic stability and transmetallation inertness while minimizing overall structural complexity. This selective modification approach allows the chelate to maintain its fundamental architecture while achieving improved performance.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The modified manganese (II) chelate compounds demonstrate improved kinetic stability and transmetallation inertness, offering a more effective and safer alternative to gadolinium-based agents, with enhanced retention and imaging capabilities.
Implementation Method 1
They work by effecting the T1, T2 and/or T2* relaxation time and thereby influence the contrast in the images. It is known that the T1, T2 and/or T2* relaxation times can be optimized for a chelated paramagnetic contrast agents by structural modification.
Data Source
AI summary
The invention provides compounds of formula (I) suitable for use as contrast agents in magnetic resonance imaging (MRI). The compounds of the present invention are manganese (II) complexes having advantageous properties as compared with similar known compounds.