Aromatic micelles: toward a third-generation of micelles

Abstract

Micelles are useful and widely applied molecular assemblies, formed from amphiphilic molecules, in water. The majority of amphiphiles possess an alkyl chain as the hydrophobic part. Amphiphiles bearing hydrophilic and hydrophobic polymer chains generate so-called polymeric micelles in water. This review focuses on the recent progress of “aromatic micelles”, formed from bent polyaromatic/aromatic amphiphiles, for the development of third-generation micelles. Thanks to multiple host-guest interactions, e.g. , the hydrophobic effect and π-π/CH-π interactions, the present micelles display wide-ranging uptake abilities toward various hydrophobic compounds in water. In addition to such host functions, new stimuli-responsive aromatic micelles with pH, light, and redox switches, aromatic oligomer micelles, saccharide-coated aromatic micelles, and related cycloalkane-based micelles were recently developed by our group.

Solution-state mechanochromic luminescence of Pt(ii)-complexes displayed within micellar aromatic capsules

“…As compared with previously reported derivatives with polyaromatic panels ( e.g. , anthracene, acridine, and phenothiazine), 12,13 PBA is transparent in the visible range ( λ > 300 nm), which is beneficial for photo-active guest molecules. Notably, an efficient coencapsulation with additives (Fig.…”

Self-Assembly Study of Block Copolypeptoids in Response to pH and Temperature Stimulation

“…Generally, for amphiphilic block copolymers in water, the hydrophobic block aggregates, and the hydrophilic block remains soluble, allowing it to form micelles. Upon increasing hydrophobicity or concentration, individual micelles coalesce into larger aggregates [ 32 ]. In this study, the block copolypeptoids experienced a transition from free molecules and micelles to big aggregates in response to temperature and pH change ( Figure 5 ).…”

Facile access to pyridinium-based bent aromatic amphiphiles: nonionic surface modification of nanocarbons in water

“…In addition, water-solubilization of graphitic carbon nitride and subsequent deposition onto a filter was achieved through a simple filtration protocol. We hope that the facile access and high modularity of PA - R will promote the wide-spread application of aromatic micelles, an emergent new class of soft molecular host compounds [ 14 – 15 30 – 31 ].…”

“…We here report pyridinium-based, bent aromatic amphiphiles PA-R, featuring a pyridinium salt (Py-R + •Cl − ) as the key motif, capable of providing both a cationic hydrophilic hinge and a variety of nonionic side-chains (i.e., CH 3 and CH 2 CH 2 (OCH 2 CH 2 ) 2 -Y (Y = OCH 3 , OH, and imidazole); Figure 1b). The present amphiphile is originated from bent aromatic amphiphile AA [12,13], composed of two anthracene panels linked by a m-phenylene spacer with two cationic sidechains, which assembles into an aqueous ≈2 nm-sized aromatic micelle with broad host functions [14][15][16][17][18][19][20][21]. Replacement of the m-phenylene unit with an N-functionalized pyridinium core reduces the synthetic steps from 6 to 2-4, while at the same time enabling the use of various nonionic side-chains.…”