Structure of sodium and rubidium taurodeoxycholate micellar aggregates and their interaction complexes with bilirubin-IX.alpha.

New Concepts in Bilirubin and Jaundice: Report of the Third International Bilirubin Workshop, April 6–8, 1995, Trieste, Italy

“…26 When pH was varied, there was no precipitation below pH 6.8, but there was formation of Ca(HB) 2 at pH 7.1 fibers (elongated aggregates) of the Na / and Rb / salts of various bile acids. [41][42][43][44][45][46] The results, supported by potential and of CaB at pH 8.2 or higher. These findings were compatible with successive ionization of the two -COOH groups be-energy calculations, point to elongated helical structures for the bile salt aggregates, with the nonpolar groups at the petween pH 7.0 and 8.5.…”

Acid Dissociation Constants of Bilirubin and Related Carboxylic Acid Compounds in Bile Salt Solutions

“…Assuming that micellar solubilization of the compounds in this study occurs by hydrophobic interaction with the non-polar faces of the bile salts, the microenvironments provided by TC and TDC would not be expected to differ greatly. It is known, however, that the size and shape of the micelles formed by these two species are different (35,36). Based on the relative polarities of the two bile salts, it can be predicted that the observed pK a values should be higher in TDC solution than in TC solution.…”

Micellar electrokinetic chromatography of tri aza aromatic ligand compounds of iron (II): Influence of bile salt type on enantiomeric separation

“…Not only do the different bile salts form micelles with different structures but the structure of any one bile salt micelle is strongly dependent on environmental conditions such as temperature, ionic strength and pH. The micelles are believed to be helical in nature and may be inside-out with the hydroxy groups oriented towards the center of the helical structure [28][29][30]. This is in contrast to at least some of the dihydroxy bile salts that appear to have a repeating trimeric subunit [26,27].…”