title: Stimuli-responsive supramolecular micellar assemblies of cetylpyridinium chloride with cucurbit[5/7]urils.
abstract: This article demonstrates, for the first time, construction of novel cucurbituril (CB)-adorned supramolecular micellar assemblies of a cationic surfactant, cetylpyridinium chloride (CPC), through noncovalent host-guest interactions. The distinct cation receptor features and cavity dimensions of the CB5 and CB7 homologues assert that the macrocyclic hosts remain complexed with the CPC monomers and take part in the micelle formation, a unique observation in contrast to that of the classical host, β-cyclodextrin. The cooperative contributions of the CB macrocycles in the micelle formation have been documented by the photochemical, surface tension, conductivity, DOSY NMR, and SANS measurements. The contrasting downward and upward shifts in the cmc of the CPC surfactant, respectively, with CB5 and CB7 hosts provide a unique opportunity for the controlled tuning of the micellization region for CPC from 0.57 to 1.6 mM, by using a combination of the macrocyclic hosts. The article also establishes the reversible response of these soft supramolecular micellar structures to thermal-stimuli, which projects their utility for on-demand smart drug-delivery vehicles.
authors.affiliation: Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India. jyotim@barc.gov.in.
authors.forename: Sharmistha Dutta
authors.initials: SD
authors.lastname: Choudhury
authors.forename: Nilotpal
authors.initials: N
authors.lastname: Barooah
authors.forename: Vinod Kumar
authors.initials: VK
authors.lastname: Aswal
authors.forename: Haridas
authors.initials: H
authors.lastname: Pal
authors.forename: Achikanath C
authors.initials: AC
authors.lastname: Bhasikuttan
authors.forename: Jyotirmayee
authors.initials: J
authors.lastname: Mohanty
mesh_terms: D001952:Bridged-Ring Compounds / Q000737:chemistry*; D002594:Cetylpyridinium / Q000737:chemistry*; D007093:Imidazoles / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D033363:Neutron Diffraction; D012492:Salts / Q000737:chemistry; D053838:Scattering, Small Angle; D013500:Surface Tension; D047392:beta-Cyclodextrins / Q000737:chemistry; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils
chemical_list: D001952:Bridged-Ring Compounds; D002594:Cetylpyridinium; D007093:Imidazoles; D008823:Micelles; D012492:Salts; D047392:beta-Cyclodextrins; C523802:cucurbit(5)uril; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils; C456276:cucurbit(7)uril; C031215:betadex