Behaviors of sodium glycochenodeoxycholate and sodium glycoursodeoxycholate in binary mixed micelles of bile salt and nonionic surfactant

✍ Scribed by Y. Takamura; S. Nakagawa; K. Suzuki; K. Takahashi; H. Asano; G. Sugihara; M. Ueno

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 572 KB
• Volume: 7
• Category: Article
• ISSN: 0927-7765
• DOI: 10.1016/0927-7765(96)01304-5

✦ Synopsis

The behavior of sodium glycochenodeoxycholate (NaGCDC) and sodium glycoursodeoxycholate {NaGUDC) in binary mixed micelles consisting of bile salt and octaoxyethylene glycol mono n-decyl ether (CloE8) has been studied on the basis of micellar compositions, polarities of the interior of intramicelles, mean aggregation numbers and ~H NMR measurements. Micellar compositions for both NaGCDC-CloE 8 and NaGUDC C10E8 systems showed a tendency to change from C10E8-rich micelles to bile-salt-rich micelles with an increase on the mole fraction of bile salts from the results of both theoretical calculations using the critical micelle concentration and the micellar polarity. The microenvironment of intramicelles for the NaGCDC CmE8 system was found to be more hydrophobic than that for the NaGUDC C~0E s system. Mean aggregation numbers of mixed micelles for both systems decreased abruptly with an increase in the mole fraction of bile salts in the range of low mole fraction, but those for NaGCDC were larger than those for NaGUDC. Furthermore, from the results of ~H NMR measurements, the motions of the methyl group protons in the 18 position of the molecular structure of NaGCDC were slightly restricted with an increase in the mole fraction of NaGCDC. In contrast, the methyl group protons in the 18 and 19 positions of the molecular structure of NaGUDC became freer with an increase in the mole fraction of NaGUDC.