Hydrogen-Bonding-Regulated Supramolecular Nanostructures and Impact on Multivalent Binding

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Biomaterials

Background:

• Bolaamphiphiles are molecules with hydrophilic groups at both ends of a hydrophobic chain.
• Hydrogen bonding plays a crucial role in directing self-assembly and molecular recognition.
• Multivalent binding involves the simultaneous interaction of multiple binding sites.

Purpose of the Study:

• To investigate the self-assembly behavior of novel naphthalene diimide (NDI)-based bolaamphiphiles.
• To explore the influence of hydrogen-bonding groups on nanostructure formation.
• To evaluate the multivalent binding properties of the formed nanostructures with concanavalin A (ConA).

Main Methods:

• Synthesis of two bolaamphiphiles, NDI-1 and NDI-2, differing in their hydrogen-bonding groups (hydrazide vs. amide).
• Characterization of self-assembled nanostructures (vesicles, cylindrical micelles, spherical micelles) using appropriate techniques.
• Assessment of multivalent binding affinity with ConA.

Main Results:

• NDI-1 formed vesicles, while NDI-2 formed cylindrical micelles due to differences in hydrogen-bonding groups.
• Both NDI-1 and NDI-2 exhibited head-to-head stacking and array formation of glucose moieties.
• The cylindrical micelles of NDI-2 demonstrated superior multivalent binding with ConA compared to NDI-1 vesicles.
• A control amphiphile without a hydrogen-bonding group formed spherical micelles with negligible binding.

Conclusions:

• Hydrogen-bonding groups are critical in dictating the self-assembly pathway and resulting nanostructures of bolaamphiphiles.
• The adaptive cylindrical micelle structure facilitates enhanced multivalent interactions.
• These findings highlight the potential of rationally designed bolaamphiphiles for applications in molecular recognition and biomaterials.