Selective Formation of Pd-DNA Hybrids Using Tailored Palladium-Mediated Base Pairs: Towards Heteroleptic Pd-DNA...

Area of Science:

• Bioinorganic Chemistry
• Molecular Biology
• Material Science

Background:

• Metal-DNA structures offer unique properties for diverse applications.
• Self-assembly processes are key to creating complex supramolecular architectures.
• Selective metal-base interactions are crucial for designing functional DNA hybrids.

Purpose of the Study:

• To synthesize a palladium-DNA supramolecular structure using a novel [Pd(Aqa)] complex.
• To investigate the self-assembly mechanism and structural characteristics of the resulting Pd-DNA complex.
• To demonstrate the selective binding of the [Pd(Aqa)] complex to cytosine.

Main Methods:

• Self-assembly of single-stranded polydeoxycytidine (dC15) with the [Pd(Aqa)] complex.
• Structural characterization using NMR spectroscopy, circular dichroism, and mass spectrometry.
• Binding affinity studies via isothermal titration calorimetry and theoretical validation using DFT calculations.

Main Results:

• Formation of a Pd-DNA supramolecular structure mimicking a natural double helix.
• Continuous [Pd(Aqa)(C)] units act as palladium-mediated base pairs, forming hydrogen bonds and stacking interactions.
• The [Pd(Aqa)] complex exhibits selective binding to cytosine, distinct from other metal complexes.

Conclusions:

• The study successfully demonstrates the formation of a highly organized Pd-DNA supramolecular structure through self-assembly.
• The [Pd(Aqa)] complex's selective binding to cytosine enables the design of heteroleptic Pd-DNA hybrids.
• These findings advance the fields of bioinorganic chemistry and material science with potential for novel DNA-based materials.