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Designing 'smart' nano carriers with high drug loading capacities and stimuli-responsive drug release behavior is crucial as they boost therapeutic efficiency while reducing side effects in patients and thereby ameliorate the limitations of traditional drug carriers. In this study, we created a ZIF-8 coated pH-responsive catanionic vesicular nano-aggregated drug delivery platform with high doxorubicin (DOX) loading capacity. The vesicular nano-aggregates were designed through synergistic interaction between the bile salt, sodium deoxycholate (NaDC), with a biocompatible ester-functionalized ionic liquid-based surfactant (ILBS), 4-methyl-4-(2-(dodecyloxy)carbonylmethyl)morpholin-4-ium bromide (C12EMorphBr). A composited drug nano-carrier was produced by coating zeolitic imidazolate framework (ZIF-8) on the surface of drug-loaded catanionic vesicular nano aggregates (DOX loaded NaDC/C12EMorphBr@ZIF-8). The study demonstrates that the ZIF-8 shell, as opposed to the catanionic vesicular system, prevents DOX leakage from the core–shell nanocomposites in response to acidic stimulation. The size of these nanocomposites was characterized using DLS, while their morphology and crystallography were examined using SEM, EDS, and XRD. These comprehensive characterizations solidify the DOX-loaded nanocomposite's integrity, affirming the successful coating of ZIF-8 on the surface of the vesicles (NaDC/C12EMorphBr). The DOX loaded NaDC/C12EMorphBr@ZIF-8 nanocomposites effectively prevented DOX leakage and early release, resulting in targeted drug delivery to the intended site. Furthermore, The DOX-loaded nanocomposite was effective in killing MCF-07 cells, with an IC50 value of 4.35 ± 0.5 μg ml−1. This effort aims to maximize the combined and independent performance of the vesicular system and coated nanocomposites. [ABSTRACT FROM AUTHOR]

The micellization of choline-based anionic surface-active ionic liquids (SAILs) having lauroyl sarcosinate [Sar]−, dodecylsulfate [DS]−, and deoxycholate [Doc]− as counter-ions was investigated in an aqueous medium. Density functional theory (DFT) was employed to investigate the net interactional energy (Enet), extent of non-covalent interactions, and band gap of the choline-based SAILs. The critical micelle concentration (cmc) along with various parameters related to the surface adsorption, counter-ion binding (β), and polarity of the cores of the micelles were deduced employing surface tension measurements, conductometric titrations and fluorescence spectroscopy, respectively. A dynamic light scattering (DLS) system equipped with zeta-potential measurement set-up and small-angle neutron scattering (SANS) were used to predict the size, zeta-potential, and morphology, respectively, of the formed micelles. Thermodynamic parameters such as standard Gibb's free energy and standard enthalpy change of micellization were calculated using isothermal titration calorimetry (ITC). Upon comparing with sodium salt analogues, it was established that the micellization was predominantly governed by the extent of hydration of [Cho]+, the head groups of the respective anions, and the degree of counter-ion binding (β). Considering the concentration dependence of the enzyme–SAIL interactions, aqueous solutions of the synthesized SAILs at two different concentrations (below and above the cmc) were utilized as the medium for testing the enzymatic activity of cellulase. The activity of cellulase was found to be ∼7- to ∼13-fold higher compared to that observed in buffers in monomeric solutions of the SAILs and followed the order: [Cho][Sar] > [Cho][DS] > [Cho][Doc]. In the micellar solution, a ∼4- to 5-fold increase in enzymatic activity was observed. [ABSTRACT FROM AUTHOR]

The evolution of phase behavior and interactions in anionic silica nanoparticles (Ludox HS40), surfactants [non-ionic decaethylene glycol mono-dodecyl ether (C12E10) and anionic sodium dodecyl sulfate (SDS)], and nanoparticle–surfactant solutions in the presence of salt (NaCl) has been studied using small-angle neutron scattering and dynamic light scattering. In an anionic silica nanoparticle solution (1 wt. %), the phase behavior is controlled by salt concentrations (0–1 M) through screening electrostatic interactions. In the case of 1 wt. % surfactant solutions, the anionic SDS surfactant micelles show significant growth upon adding salt, whereas non-ionic surfactant C12E10 micelles remain spherical until a high salt concentration (1 M). In the mixed system of HS40–C12E10, a transition from a highly stable transparent phase to a two-phase turbid system is observed with a small amount of salt addition CS* (∼0.06 M). The single transparent phase of this system corresponds to sterically stabilized micelles-decorated nanoparticles. For the turbid phase, the results are understood in terms of depletion attraction induced by non-adsorption of C12E10 micelles, which explains the appearance of turbidity at a much lower concentration of salt. In the mixed system of similarly charged nanoparticles and micelles (HS40-SDS), the phase behavior is governed by no physical interaction between the components, and salt screens the repulsive interaction among nanoparticles. These results are further utilized to tune multicomponent interactions and phase behavior of nanoparticles with a mixed C12E10-SDS surfactant system in the presence of salt. The mixed surfactants provide tuning of nanoparticle–micelle as well as micelle–micelle interactions to dictate the phase behavior of a nanoparticle–surfactant solution. In these systems, the effective potential can be described by double-Yukawa potential taking account of attractive and repulsive parts at low and intermediate salt concentrations (CS*), the aggregation of nanoparticles is characterized by fractal aggregates. [ABSTRACT FROM AUTHOR]