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Interactional study of triphenylmethane-based cationic dye i.e., basic violet-4 dye (BV) in the mixed-micellar system of two anionic surfactants viz. sodium dodecyl sulfate (NaDS) and sodium stearate (NaS) is encompassed in this manuscript. The composite micelles of nonionic surfactant triton X-100 (TX) served as better colloidal carriers to facilitate aggregation, deep penetration, and stability of dye molecules than single surfactants. The thermodynamics of the micellization was assessed conductometrically, whereas the extent of dye-surfactant interaction was quantified spectroscopically. The nonionic/anionic mixture favored micellization and lowered critical micellar concentration (CMC). Furthermore, it is observed that dye partitioning, binding, and micellization were spontaneous processes. The thermodynamic parameters including entropy, enthalpy, and Gibb's free energy of micellization along with the determination of the CMC, degree of ionization are also explained. The parameters in terms of partition constant, partition coefficient, binding constant, Gibb's free energy of partition, and binding were calculated from differential absorption spectroscopy. The comparative study revealed that NaDS/TX showed superior performance in dye penetration as compared to NaS/TX system. [ABSTRACT FROM AUTHOR]

In this manuscript, a study on interactions of a polymeric derivative of Tributyltin(IV) with [(2-Methylpropanoyl)amino]propanoic acid (TMP) in micellar media is presented. The study was conducted using two surfactants viz. Sodium 2-ethylhexylsulphate (SES) and Cetyltrimethylammonium bromide (CTAB). The solubilization parameters in terms of partition constant (Kc), partition coefficient (Kx), binding constant (Kb), Gibb's free energy of partition (ΔGp), and binding (ΔGb) were investigated by UV–Visible spectrophotometer. The estimation of micellization thermodynamics including entropy (ΔSm), enthalpy (ΔHm), and Gibb's free energy (ΔGm) were determined conductometrically. The compound showed more interaction with the cationic surfactant as compared to anionic participating surfactant due to comparative electrostatic interactions. The partition coefficient (Kx) in the micellar media of CTAB was significantly higher (4.22 × 107) than SES media (1.33 × 105). The Gibb's free energies of partition. Binding and micellization were higher in CTAB as compared to SES. [ABSTRACT FROM AUTHOR]

Physicochemical attributes and solubilization of reactive dyes in single and mixed micellar media are elaborated in this study. The enhanced entrapment of reactive dyes was observed in the mixed-micellar media of cationic surfactant, cetyltrimethylammonium bromide (CTAB) and nonionic surfactant, (Triton X-100) as compared to single-micellar media of CTAB. Two reactive dyes viz. Reactive Black 5 (RB) and Reactive Yellow 145 (RY) were used for this interactional study. The solubilization in terms of partition constant (Kc), partition coefficient (Kx), binding constant (Kb), Gibbs free energies (ΔGp and ΔGb) and the approximate location of dye molecules in the micelles, was assessed by UV–Vis spectroscopy. From the experimental findings, it was concluded that the mixing of CTAB with a nonionic surfactant is recommended to achieve a superior degree of entrapment of dye molecules as compared to the single surfactant. The RB, the magnitude of Kx was 520 × 105 in CTAB media, whereas this value lowered to 195 × 105 in the mixed-micellar system (MMS). A similar trend was observed in RY and the single and MMSs showed respective Kx values of 207 × 105 and 19.7 × 105. The higher negative magnitudes in the case of single surfactant indicated greater partitioning of dyes while the mixed system caused deep penetration of dyes. The lower values of Gibb's free energies of partition and binding were indicative of greater penetration of dyes within the micelles. [ABSTRACT FROM AUTHOR]

The solubilization behavior of hexanuclear copper complex, [Cu6(η1:μ2-C4H10NO)4(η1:η1:μ2-C5H9O2)4(η1:μ1-C5H9O2)2(μ3-OH)2] (1) (where, C4H10NO = N,N-dimethylethanolamine and C5H9O2 = pivalic acid) ionic micellar media has been explored in this study. The interaction of copper cluster under investigation (1) was experimented with an anionic surfactant (sodium lauryl sulfate; SLS) and a cationic surfactant (cetyltrimethyl ammonium bromide; CTAB). Solubilization was observed in aqueous solutions of ionic surfactants at their pre-micellar, micellar and post-micellar concentrations ranges using UV–Visible spectroscopy and electrical conductivity. The thermodynamic attributes of micellization including standard entropy (ΔSmic), enthalpy (ΔHmic) and free energy (ΔGmic) were estimated from electrical conductivity measurements. The negative values of ΔGmic and ΔHmic indicated the stability of micellization, in addition to the enthalpy and entropy-driven nature of the process. Thermodynamic studies demonstrate increases in the CMC of both surfactants due to incorporation of the copper complex in the micelles. Partitioning and binding parameters were revealed by UV–Vis spectroscopy to quantitatively measure the interaction of the copper cluster with the surfactant in terms of partition constant (Kc), partition coefficient (Kx), binding coefficient (Kbind), and free energies of free energy of partition (ΔGpart) and binding (ΔGbind). The presence of cationic CTAB led to greater red-shift in UV–Vis study of 1 as compared to SLS due to stronger ionic interactions. The strong interaction and high solubility have been seen in 1 with CTAB as compared to SLS. Hexanuclear copper complex reveals the strong interaction and high solubilization with CTAB in comparison to SLS due to high degree of dissociation and significant electrostatic interactions with CTAB. [ABSTRACT FROM AUTHOR]

Summary: This manuscript has reported the micellar interaction of cationic triphenylmethane-based dye "Victoria Blue-B (VBB)". The study was conducted using ionic surfactants viz. Cetyltrimethylammonium Bromide (CTAB)] Sodium Dodecyl Sulphate (SDS), and Sodium Docusate (SD). The behavior of dye in micellar media at concentration ranges of the surfactants mentioned above was monitored by UV-vis absorption spectroscopic study. The solubilization parameters to reveal the interaction of cationic dye in micellar media were assessed. The mathematical calculations of partition constant (Kc), partition coefficient (Kx), binding coefficient (Kb), Gibb's free energy for partition (ΔGp) and binding (ΔGb) were derived from UV-Vis absorption data. The presence of anionic surfactants caused more bathochromic shifts in the maximum absorption of the dye, which was indicative of strong interactions as compared to the cationic surfactant. [ABSTRACT FROM AUTHOR]

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