title: Determination of critical micellar concentrations of cholic acid and its keto derivatives.
abstract: The critical micellar concentration (CMC) values of keto derivatives of cholic acid (3alpha,12alpha-dihydroxy-7-oxo-5beta-cholanoic acid, 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanoic acid, 12alpha-hydroxy-3,7-dioxo-5beta-cholanoic acid, 3alpha-hydroxy-7,12-dioxo-5beta-cholanoic acid, 3,7,12-triketo-5beta-cholanoic acid) and cholic acid itself, were determined. Replacement of hydroxyl groups in cholic acid molecule with keto groups yields the derivatives whose CMC values increase with increase in the number of keto groups introduced. The CMCs of derivatives with the same number of keto groups but at different positions do not differ significantly. The relationship between the number of keto groups in the molecule of cholic acid keto derivatives and CMC value can be described by the following equation: CMC=43 number of keto groups+14.667. The effect of NaCl concentration on CMC increases with increase in the number of keto groups.
authors.affiliation: Department of Pharmacy, Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000 Novi Sad, Serbia.
authors.forename: Mihalj
authors.initials: M
authors.lastname: Posa
authors.forename: Slavko
authors.initials: S
authors.lastname: Kevresan
authors.forename: Momir
authors.initials: M
authors.lastname: Mikov
authors.forename: Vera
authors.initials: V
authors.lastname: Cirin-Novta
authors.forename: Costel
authors.initials: C
authors.lastname: Sârbu
authors.forename: Ksenija
authors.initials: K
authors.lastname: Kuhajda
mesh_terms: D019826:Cholic Acid / Q000032:analysis* / Q000737:chemistry; D002793:Cholic Acids / Q000032:analysis / Q000737:chemistry; D004396:Coloring Agents; D003685:Dehydrocholic Acid / Q000032:analysis / Q000737:chemistry; D008027:Light; D008823:Micelles; D012542:Scattering, Radiation; D012995:Solubility; D013050:Spectrometry, Fluorescence; D013194:Staining and Labeling; D014867:Water
chemical_list: D002793:Cholic Acids; D004396:Coloring Agents; D008823:Micelles; D014867:Water; D019826:Cholic Acid; D003685:Dehydrocholic Acid; C007036:cholanic acid