Interactions between Sodium Cholate or Sodium Deoxycholate and Nonionic Surfactant (Tween 20 or Tween 60) in Aqueous Solution

Abstract

Knowledge of physicochemical parameters of mixed micelles is important in order to develop drug delivery systems with required characteristics. Investigated bile salts and Tweens are relatively nontoxic surfactants, extensively studied as biocompatible colloidal drug carriers. The micellization behavior of binary anionic–nonionic surfactant mixtures built of sodium cholate or sodium deoxycholate and one of two Tweens (Tween 20 or Tween 60) was investigated by conductivity and surface tension measurements. The results of the study have been analyzed using Clint’s, Rubingh’s, and Motomura’s theories for mixed binary systems. The determined physicochemical properties, particularly the negative values of the interaction parameter, indicate synergism between the individual surfactants in the mixed micelles. It was noticed that Tween with a longer hydrophobic tail shows stronger interactions with selected bile salts. However, it was found that the more hydrophilic bile salt (sodium cholate) generates the stronger synergism with investigated Tweens.

Conductivity and fluorescence studies on the micellization properties of sodium cholate and sodium deoxycholate in aqueous medium at different temperatures: Effect of selected amino acids

“…The concentration corresponding to these break points has been identified with the critical micelle concentration (CMC) of bile salts and determined as cited in literature [31]. However, it is important to mention that the break points in these plots are not sharp (figure 3), which has been a feature associated with aqueous solutions of bile salts [33,34] and can be attributed to a stepwise micellization process instead of an instantaneous micelle formation process [35]. In a stepwise micellization process, bile salts firstly are known to form the primary micelles due to the hydrophobic interactions between their hydrophobic parts in aqueous solutions.…”

“…After this, the secondary micelles are formed with further increase in bile salts concentration due to the hydrogen bonding among the hydroxyl groups of the primary micelles. In this context, the analysis of literature [33,34,11,1,10,36] reveals that CMC values of bile salts derived from the different methods or even from same method by different researchers are not always comparable. Therefore, it is impossible to define a single CMC value in case of bile salts.…”

Investigations on microstructural changes in pH responsive mixed micelles of Triton X-100 and bile salt

“…Sambhakar et al [44] solubilized an antibiotic drug cefuroxime axetil in micelles of nonionic Spans and stabilized these formulations by NaDC. The micellization of binary mixture of bile salts and nonionic Tweens showed stronger synergism [45,46]. Mixed micellization of TX-100 + bile salts has also been reported [47,48].…”

“…Two important bile salts NaC and NaDC are the most abundant in human body [1] and their solution behaviour in mixed systems with other conventional surfactants have been studied in detail [6,[34][35][36][37][38][39][40][41][42][43][44][45][46][47][48]. Influence of these bile salts on aggregation characteristics of anionic [6, 34], cationic [35][36][37][38][39][40], zwitterionic [16,41] and nonionic surfactants [42][43][44][45][46][47][48] have been reported. Ueno et al [42] studied the physicochemical properties of mixed micelles formed by octaoxyethylene glycol mono n-decyl ether (C 10 E 8 ) and variety of bile salts using 1 H NMR spectroscopy and revealed that the magnitude of interaction mostly depends upon the number and position of -OH groups and the hydrophobicity of bile salt.…”

Thermodynamics of micellisation: Sodium dodecyl sulfate/sodium deoxycholate with polyethylene glycol and model drugs

“…As a comparison, the former generally has a greater CMC value (yet a similar thermodynamic profile) than the latter. Sodium deoxycholate is used in pharmaceutical formulations to solubilise poorly soluble molecules and is known to form micelles and mixed micelle systems such as with Tweens [6]. The aggregation behaviour of NaDC has been reported with CMC values in the range 5.3 to 10.5 [7; 8; 9; 10; 11] with a clear temperature dependence.…”