Physico-chemical investigation of asymmetrical peptidolipidyl-cyclodextrins.
A new class of amphiphilic peptidolipidyl-cyclodextrins is reported. The derivatives are chiral due to the presence of an L-leucine in the spacer arm that links a saccharide moiety and a grafted, saturated hydrocarbon chain. Self-assembly properties of the peptidolipidyl-cyclodextrins are characterized by quasi-elastic light scattering, turbidity and UV-visible absorption measurements. NMR experiments give insight into the intermolecular dipolar interactions as a function of temperature and concentration. N-dodecyl-N alpha-(6 I-amidosuccinyl-6 1-deoxy-cyclomaltoheptaose)-L-leucine (1) is poorly soluble in aqueous media. N-dodecyl-N(alpha)-(6 I-amidosuccinyl-6 I-deoxy-2 I,3 I-di-O-methyl-hexakis-(2 II-VII,3 II-VII,6 II-VII-tri-O-methyl)-cyclomaltoheptaose)-L-leucine (2) is found to be more soluble and self-assembles into stable supramolecular colloidal aggregates with nanometric dimensions above a critical aggregation concentration (CAC). It has a propensity for solubilization of hydrophobic species revealing a micellar-like behavior, which is compared to that of the non-ionic detergent octyl glucoside. On the contrary, compound 1 precipitates in a crystalline phase beyond its water solubility limit, and it does not display any solubilizing capacity. The observed behavior corroborates at the molecular level with the NMR results.
Angelova
Angelina
A
CNRS UMR8612 Physico-chimie, Pharmacotechnie, Biopharmacie, Equipe Physico-chimie des Systèmes Polyphasés, Université Paris Sud, Châtenay-Malabry Cedex, F-92290 France.
Fajolles
Christophe
C
Hocquelet
Céline
C
Djedaïni-Pilard
Florence
F
Lesieur
Sylviane
S
Bonnet
Véronique
V
Perly
Bruno
B
Lebas
Geneviève
G
Mauclaire
Laurent
L
D000042:Absorption; D003102:Colloids / Q000737:chemistry; D003505:Cyclodextrins / Q000737:chemistry*; D003902:Detergents / Q000737:chemistry*; D005960:Glucosides / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D007930:Leucine / Q000031:analogs & derivatives; D008055:Lipids / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D009391:Nephelometry and Turbidimetry; D010455:Peptides / Q000737:chemistry*; D012542:Scattering, Radiation; D012995:Solubility; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D014867:Water / Q000737:chemistry
D003102:Colloids; D003505:Cyclodextrins; D003902:Detergents; D005960:Glucosides; D008055:Lipids; D008823:Micelles; D010455:Peptides; D014867:Water; C018619:octyl-beta-D-glucoside; D007930:Leucine