ATP-responsive Mn(II)-based T₁ contrast agent for MRI.

Area of Science:

• Biochemistry
• Medical Imaging
• Materials Science

Background:

• Adenosine triphosphate (ATP) is a crucial biomarker in biological processes.
• Developing targeted contrast agents for magnetic resonance imaging (MRI) remains a significant challenge.
• Existing MRI contrast agents lack specificity for biological analytes like ATP.

Purpose of the Study:

• To synthesize and characterize a novel manganese(II) chelate, MnLDPA-Zn2, for ATP-responsive MRI.
• To evaluate the relaxivity of MnLDPA-Zn2 and its response to ATP binding.
• To explore its potential as a T1 contrast agent for selective ATP detection.

Main Methods:

• Synthesis of a diacetylpyridylcarbohydrazide-based manganese(II) chelate incorporating dipicolylamine/zinc(II) arms.
• Relaxivity measurements of the synthesized compound in the presence and absence of various phosphate species.
• Characterization of the compound's binding affinity and selectivity for ATP.

Main Results:

• The novel MnLDPA-Zn2 chelate was successfully synthesized.
• The compound exhibited significantly enhanced relaxivity (r1 = 11.52 mM⁻¹ s⁻¹) upon selective binding to ATP.
• Demonstrated superior selectivity for ATP over other phosphate molecules, including ADP and inorganic phosphate.

Conclusions:

• MnLDPA-Zn2 is a promising ATP-responsive MRI T1 contrast agent.
• Its selective ATP binding and enhanced relaxivity offer potential for targeted biological imaging.
• This development opens new avenues for non-invasive monitoring of ATP-related biological processes using MRI.