Facial Amphiphilicity-Induced Self-Assembly (FAISA) of Amphiphilic Copolymers

Abstract

Amphiphilic molecules, including macromolecules and small surfactants, inherently self-assemble into a wide variety of nanostructures in selective solvents. However, the sequential structure for synthetic polymers is largely restricted to block copolymers. In this work, we report facial amphiphilicity-induced self-assembly (FAISA) of gradient amphiphilic copolymers. This new approach is demonstrated using facial amphiphilic multicyclic compounds. The facial amphiphilicity of bile acids allows cationic copolymers to form aggregates with different morphologies in aqueous solution. By tuning the compositions of hydrophilic and hydrophobic segments, these copolymers can self-assemble in water to produce spherical, vesicle, and rodlike nanostructures via supramolecular and electrostatic interactions. The hydrophobic interaction from multicyclic hydrocarbon moieties largely dictates the self-assembly process, which can be further modulated by integrating neutral hydrophilic poly(ethylene glycol) in copolymer compositions with additional stimuli such as temperature, charge density, and ionic screening.

Physiology and Physical Chemistry of Bile Acids

“…Moreover, a class of BA-based antibiotics termed Ceragenins have been prepared by covalently attaching amines to BAs, inspired by the molecular structure of squalamine, a naturally occurring aminosterol with potent antimicrobial activity, isolated from shark liver [ 101 , 102 , 103 ]. Similar molecules have been linked as pendants to polymers able to locally cluster the facial amphiphilicity of these cationic steroid antibiotics, thereby enhancing interactions with bacterial membranes [ 104 , 105 , 106 ] ( Figure 3 g–i). To date, BAs are actually used both as precursor and co-agent in drug formulation.…”

Playing construction with the monomer toy box for the synthesis of multi‐stimuli responsive copolymers by reversible deactivation radical polymerization protocols

“…Rahman et al 189 synthesized random and block copolymers of OEGMA and bile acid methacrylic derivatives to explore the effect of hydrophobic interactions, charge density and monomers distribution on aggregation induced by facial amphiphilicity‐induced self‐assembly (FAISA). The Authors also showed that the aggregates respond to temperature and ion screening.…”

Recent Progress in Bile Acid-Based Antimicrobials

“…54−56 Recently, the literature has reported antibacterial polymers bearing quaternary ammonium decorated BA pendants, and these polymeric antibacterials are endowed with durable antibacterial property and hypotoxicity. 36,32,57,58 Some steroid−amino acid conjugates and some bile acid−bioactive molecule conjugates have been reviewed in the applications of medicinal chemistry and material science, 59,60 but there is no specific review to summarize the recent progress in bile acidbased antimicrobials. Herein, this review puts an emphasis on the role of BAs in development of antimicrobials classified by the number of BA units, including unimolecular, oligomeric, and macromolecular antimicrobials.…”

“…In the past decades, through utilizing facial amphiphilic structures of BAs, there have been extensive efforts in the development of bile acid-based antimicrobials in which BA skeletons were conjugated with some positive segments, such as primary amine and quaternary ammonium. For example, Savage and co-workers developed a series of ceragenins to mimic cationic, facial amphiphilic structures of most AMPs by the use of a BA scaffold and appended amine groups. − Recently, the literature has reported antibacterial polymers bearing quaternary ammonium decorated BA pendants, and these polymeric antibacterials are endowed with durable antibacterial property and hypotoxicity. ,,, Some steroid–amino acid conjugates and some bile acid–bioactive molecule conjugates have been reviewed in the applications of medicinal chemistry and material science, , but there is no specific review to summarize the recent progress in bile acid-based antimicrobials. Herein, this review puts an emphasis on the role of BAs in development of antimicrobials classified by the number of BA units, including unimolecular, oligomeric, and macromolecular antimicrobials.…”