Taurocholate and Taurodeoxycholate: Gel Formation and Protonation Constants

Abstract

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.

Solubility and the Solubility Product of Some Calcium(II) Salts of Bile Acids

“…The excess was in any case very limited so that the formation of micellar aggregates was avoided. Few sodium salts of the studied bile acid have been studied, − and some species explained the experimental data satisfactorily. For such bile salts a greater excess of sodium bile salt could be added because, as explained below, the knowledge of the sodium–bile salt system was very useful.…”

“…The influence of the ionic composition of the solution on the behavior of sodium glycocholate and cholate, gel formation, and protonation constants of taurocholate and taurodeoxycholate were investigated.…”

Modified Low Molecular Weight Pure and Engineered Gels: A Review of Strategies towards Their Development

“…Likewise NaDC, other bile salts like sodium salts of lithocholate, taurocholate and taurodeoxycholate also form hydrogels, Antonilli et al [132] . have established the gelation of taurocholate and taurodeoxycholate and also studied their gelation in the presence of salts.…”

“…[130][131] Over the past few decades, the researchers have shown a great interest for the development of bile salts and bile salt derivative-based hydrogels as they are biocompatible, thermally reversible, biodegradable and thus useful in the field of pharmaceutical applications such as drug delivery. [2] Likewise NaDC, other bile salts like sodium salts of lithocholate, taurocholate and taurodeoxycholate also form hydrogels, Antonilli et al [132] have established the gelation of taurocholate and taurodeoxycholate and also studied their gelation in the presence of salts. The gelation in aqueous medium of sodium lithocholate is also studied by Pierre Terech and its co-workers [133] and they have also examined the effect of salts on the morphology of the hydrogels.…”