On the Composition of Sodium Taurodeoxycholate Micellar Solutions

Bottari, Emilio; Festa, Maria Rosa

doi:10.1021/la950616f

Cited by 43 publications

(70 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The same gel formation is favoured by high bile salt and hydrogen ion concentration. This conclusion agrees well with experiments carried out in previous researches 12,13 . The gel formation takes place more easily in TDC than in TC solutions.…”

Section: Resultssupporting

confidence: 94%

“…From the protonation constants of the two investigated bile salts, it can be deduced that their protonation to form the corresponding acid takes place only at high hydrogen ion concentration (-log c H ≤ 2). Previously, it was found that the formation of protonated micellar species started at lower c H both for TDC (-log c H ≤ 7.5) and for TC (-log c H ≤ 4), respectively 12,13 .…”

Section: Resultsmentioning

confidence: 97%

“…This result agrees well with that obtained under the same experimental conditions in previously papers. Previously 12,13 , by employing as ionic medium (0.100, 0.200, 0.300, 0.400. 0.500 and 0.750 mol dm -3 ) N(CH 3 ) 4 Cl, gel formation was never observed.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Taurocholate and Taurodeoxycholate: Gel Formation and Protonation Constants

2006

Self Cite

View full text Add to dashboard Cite

Taurocholate (TC) and taurodeoxycholate (TDC) in aqueous solutions, in the presence of sodium and hydrogen ions can give micellar products, even differently protonated. This phenomenon is investigated in this paper to explain whether the assumption of hydrogen ions is to attribute to the micellar aggregates, or to the protonation of taurocholate and taurodeoxycholate, respectively.In the course of this research, often the formation of gel occurred immediately after the mixture of the reagents (sodium, hydrogen ions and anions of bile acids) or after some time, depending on the concentrations of the reagents. No author mentions this evidence, but experiments carried out in the presence of gel are not reproducible because the investigated solutions cannot be considered in real equilibrium.The protonation study was performed by means of electromotive force measurements of a galvanic cell involving a glass electrode, at 25°C and 1.00 mol dm‐3 NaCl, as ionic medium. The obtained protonation constants had the following values: log k1 = 0.07 ± 0.02 for TC and log k'1 = 1.60 ± 0.03 for TDC.

show abstract

Section: Resultssupporting

confidence: 94%

Section: Resultsmentioning

confidence: 97%

See 1 more Smart Citation

Taurocholate and Taurodeoxycholate: Gel Formation and Protonation Constants

2006

Self Cite

View full text Add to dashboard Cite

show abstract

“…An earlier investigation on solutions of NaTDC (Bottari and Festa, 1996) was carried out at 25 C and in N(CH 3 ) 4 Cl medium at seven different concentrations: 0.100, 0.200, 0.300, 0.400, 0.500, 0.600 and 0.750 mol dm À 3 . The results obtained at 0.500 mol dm À 3 were useful for taking into account the formation of aggregates between sodium and TDC, without calcium(II).…”

Section: Introductionmentioning

confidence: 99%

An investigation on calcium taurodeoxycholate micellar aggregates

Antonilli

Bottari

Festa

et al. 2010

Chemical Speciation & Bioavailability

Self Cite

View full text Add to dashboard Cite

The formation of micellar aggregates in the presence of calcium(II) ions in solutions containing sodium and taurodeoxycholate ions and their composition at 25 C and in 0.5 mol dm À 3 N(CH 3 ) 4 Cl as constant ionic medium was studied. The study was carried out by means of two different procedures. In the first one, solid calcium oxalate was equilibrated with taurodeoxycholate, sodium and hydrogen ions and the free concentration of sodium and hydrogen ions was determined. After filtration, the calcium(II) (by atomic absorption spectrophotometry) and oxalate concentration were also determined. In the second approach, hydrogen and sodium ions free concentrations were obtained by electromotive force measurements carried out in solutions containing taurodeoxycholate. The results of both procedures could be explained by assuming the presence of aggregates of different composition with the participation of sodium, calcium(II) and taurodeoxycholate ions, depending on the concentration of the reagents. Protonated species were even present in appreciable concentrations. All the found species have taurodeoxycholate aggregation numbers in multiples of three. A mechanism for the micellar aggregates containing calcium and sodium is proposed. Sodium taurodeoxycholate in the presence of calcium(II) forms larger aggregates than does taurocholate in the presence of calcium(II); the building block of the former is a trimer whereas the latter system has lower aggregation numbers and its building block is a dimer or an octamer.

show abstract

“…The behaviour of anions of some salts of dihydroxycholanic bile acids, like deoxycholate (DC -) (Bottari et al 1985;1989), glycodeoxycholate (GDC -) (Bottari and Festa, 1993) and taurodeoxycholate (TDC -) (Bottari and Festa, 1996) was studied previously.…”

Section: Introductionmentioning

confidence: 99%