It remains a challenging task to control the functional group display at the inner or outer surface of a vesicle at will. We have recently solved this classical problem by H-bonding functional group attached π-Amphiphiles. Basically, driven by the motivation to form extended H-bonding, both A-1 and A-2 undergo unidirectional orientation and furthermore the propensity of the H-bonded chain to remain at the inner wall ensures display of the functional group attached to the H-bonded arm at the inner wall while the functional group attached with the other arm are displayed at the outer surface. This has been tested with a series of unsymmetric bolaamphiphiles having different anionic head groups. Subsequent studies demonstrate the possibilities of precisely tuning the size and surface charge density of such vesicles by systematic variation of the structure of the ionic head groups which was reflected in their ability to inhibit the enzymatic activity of ChT. Most recently, H-bonding regulated functional group display has also been verified by the glycol-cluster effect exhibited by sugar-functionalized similar π-amphiphiles. Hydrazide containing bolaamphiphile produces unsymmetric membrane leading to effective display of the sugar moieties at the vesicular surface which enables much efficient binding with ConA compared to control molecule lacking any H-bonding group. Interestingly when the hydrazide group was replaced by amide, the amphiphile revealed cylindrical micellar structure which showed even better multivalent effect for interaction with biological targets owing to the more adaptable nature of cylindrical structure than vesicle. Very recently we have explored such directional assembly with cationic derivatives and shown strong impact in their antimicrobial activity. We also have used such self-assembly motifs for protein assembly, supramolecular protein-polymer conjugation and stimuli responsive activity tuning. Highlights of these results will be described in the presentation.

H-bonding regulated directional supramolecular assembly and functional biomaterial

ACS Fall 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.