TY - JOUR
T1 - Generation of a Chiral Giant Micelle
AU - Ito, Thiago H.
AU - Salles, Airton G.
AU - Priebe, Jacks P.
AU - Miranda, Paulo C.M.L.
AU - Morgon, Nelson H.
AU - Danino, Dganit
AU - Mancini, Giovanna
AU - Sabadini, Edvaldo
N1 - Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/8/23
Y1 - 2016/8/23
N2 - Over the past few years, chiral supramolecular assemblies have been successfully used for recognition, sensing and enantioselective transformations. Several approaches are available to control chirality of discrete assemblies (e.g., cages and capsules), but few are efficient in assuring chirality for micellar aggregates. Optically active amino acid-derived surfactants are commonly used to generate chiral spherical micelles. To circumvent this limitation, we benefited from the uniaxial growth of spherical micelles into long cylindrical micelles usually called wormlike or giant micelles, upon the addition of cosolutes. This paper describes the unprecedented formation of chiral giant micelles in aqueous solutions of cetyltrimethylammonium bromide (CTAB) upon increasing addition of enantiopure sodium salt of 1,1′-bi-2-naphthol (Na-binaphtholate) as a cosolute. Depending on the concentrations of CTAB and Na-binaphtholate, chiral gel-like systems are obtained. The transition from spherical to giant micellar structures was probed using rheology, cryo-transmission electron microscopy, polarimetry, and electronic circular dichroism (CD). CD can be effectively used to monitor the incorporation of Na-binaphtholate into the micelle palisade as well as to determine its transition to giant micellar structures. Our approach expands the scope for chirality induction in micellar aggregates bringing the possibility to generate "smart" chiral systems and an alternative asymmetric chiral environment to perform enantioselective transformations.
AB - Over the past few years, chiral supramolecular assemblies have been successfully used for recognition, sensing and enantioselective transformations. Several approaches are available to control chirality of discrete assemblies (e.g., cages and capsules), but few are efficient in assuring chirality for micellar aggregates. Optically active amino acid-derived surfactants are commonly used to generate chiral spherical micelles. To circumvent this limitation, we benefited from the uniaxial growth of spherical micelles into long cylindrical micelles usually called wormlike or giant micelles, upon the addition of cosolutes. This paper describes the unprecedented formation of chiral giant micelles in aqueous solutions of cetyltrimethylammonium bromide (CTAB) upon increasing addition of enantiopure sodium salt of 1,1′-bi-2-naphthol (Na-binaphtholate) as a cosolute. Depending on the concentrations of CTAB and Na-binaphtholate, chiral gel-like systems are obtained. The transition from spherical to giant micellar structures was probed using rheology, cryo-transmission electron microscopy, polarimetry, and electronic circular dichroism (CD). CD can be effectively used to monitor the incorporation of Na-binaphtholate into the micelle palisade as well as to determine its transition to giant micellar structures. Our approach expands the scope for chirality induction in micellar aggregates bringing the possibility to generate "smart" chiral systems and an alternative asymmetric chiral environment to perform enantioselective transformations.
UR - http://www.scopus.com/inward/record.url?scp=84983611728&partnerID=8YFLogxK
U2 - 10.1021/acs.langmuir.6b02367
DO - 10.1021/acs.langmuir.6b02367
M3 - 文章
AN - SCOPUS:84983611728
SN - 0743-7463
VL - 32
SP - 8461
EP - 8466
JO - Langmuir
JF - Langmuir
IS - 33
ER -