High-Affinity DNA Base Analogs as Supramolecular, Nanoscale Promoters of Macroscopic Adhesion

Abstract

Adhesion phenomena are essential to many biological processes and to synthetic adhesives and manufactured coatings and composites. Supramolecular interactions are often implicated in various adhesion mechanisms. Recently, supramolecular building blocks, such as synthetic DNA base-pair mimics, have drawn attention in the context of molecular recognition, self-assembly, and supramolecular polymers. These reversible, hydrogen-bonding interactions have been studied extensively for their adhesive capabilities at the nano- and microscale, however, much less is known about their utility for practical adhesion in macroscopic systems. Herein, we report the preparation and evaluation of supramolecular coupling agents based on high-affinity, high-fidelity quadruple hydrogen-bonding units (e.g., DAN·DeUG, Kassoc = 10(8) M(-1) in chloroform). Macroscopic adhesion between polystyrene films and glass surfaces modified with 2,7-diamidonaphthyridine (DAN) and ureido-7-deazaguanine (DeUG) units was evaluated by mechanical testing. Structure-property relationships indicate that the designed supramolecular interaction at the nanoscale plays a key role in the observed macroscopic adhesive response. Experiments probing reversible adhesion or self-healing properties of bulk samples indicate that significant recovery of initial strength can be realized after failure but that the designed noncovalent interaction does not lead to healing during the process of adhesion loss.

Computational study of the thermodynamic stabilities of hydrogen-bonded complexes in solution

“…Zimmerman and coworkers measured the binding free energy of 3-4 in CHCl 3 solvent by ITC. The 3-4 complex with a DAAD-ADDA H-bonding array was subsequently used to form highly selective nanoscale adhesive agents [7]. Our M06-2X and SMD/cc-pVDZ calculated free energy of association of −11.10 kcal/mol for 3-4 is in excellent agreement with the experimental value of −11.3 kcal/mol in chloroform, which once again demonstrates the reliability of our computational procedures and approximations.…”

Supramolecular network-based self-healing polymer materials

“…To sum up, this is a complicated system that has strong application potential and is worth studying. Anderson et al [46] reported that for supramolecular coupling agents based on high-affinity, high-fidelity quadruple hydrogen-bonding units, the DNA base-pair mimics 2,7-diamidonaphthyridine (DAN) and ureido-7-deazaguanine (DeUG) (Figure 7.7). The DeUG-DAN supramolecular system is a type of enhanced DNA base pair, showing significantly higher stability and affinity than adenine-thymine and guanine-cytosine.…”

“…The DAN-DeUG complex serves as the reversible noncovalent bond between the adhesive and the adherend. Reproduced from Ref [46]. with permission from ACS.…”

Macroscopic Self‐Assembly Based on Complementary Interactions between Nucleobase Pairs

“…[29] More recently, there have been some reports on macroscopic adhesion systems based on various noncovalent interactions, as represented by dynamic covalent bonds, [30,31] ion-ion interactions, [32,33] hydrogen bonds, [34] and so on. [35] Most recently, a DNA-based gel assembly system was developed by using a DNA polymerase-mediated rolling circle amplification (RCA) method on the surface of a gel; [36] alternatively, we have been studying gel assembly by using oligonucleotides.…”