Drug‐Induced Micelle‐to‐Vesicle Transition of a Cationic Gemini Surfactant: Potential Applications in Drug Delivery

Abstract

An impetus for the sustained interest in the formation of vesicles is their potential application as efficient drug-delivery systems. A simple approach for ionic surfactants is to add a vesicle-inducing drug of opposite charge. In ionic gemini surfactants (GSs) two molecules are covalently linked by a spacer. Regarding drug delivery, GSs are more attractive candidates than their single-chain counterparts because of their high surface activity and the effect on the physicochemical properties of their solutions caused by changing the length of the spacer and inclusion of heteroatoms therein. Herein, the effect of the (anionic) anti-inflammatory drug diclofenac sodium (DS) on the morphology of aqueous micellar aggregates of gemini surfactant hexamethylene-1,6-bis (dodecyldimethylammonium) dibromide (12-6-12) at 25 °C is reported. Several independent techniques are used to demonstrate drug-induced micelle-to-vesicle transition. These include UV/Vis spectrophotometry, dynamic light scattering, TEM, and small-angle neutron scattering. The micelles are transformed into vesicles with increasing [DS]/[12-6-12] molar ratio; precipitation of the catanionic (DS-GS) complex then occurred, followed by partial resuspension of the weakly anionic precipitate. The stability of some of the prepared vesicles at human body temperature shows their potential use in drug delivery.

Temperature‐Responsive Low Molecular Weight Ionic Liquid Based Gelator: An Approach to Fabricate an Anti‐Cancer Drug‐Loaded Hybrid Ionogel

“…The self-assembly behaviour of CetPySal in aqueous medium was performed using multi technique approach. [32][33][34][35][36]48] Surface active and micellization parameters derived from the surface tension and conductivity measurements are reported in Table 1 and are compared with precursor surfactant CPCl. [48] Plots of surface tension and specific conductivity (k) versus [CetPySal] are shown in Figure 1.…”

“…Our group is engaged in designing various amphiphilic molecules for their tailor made interfacial and micellar properties, ionic liquid based surfactants (ILBS) with better surface active and micellar properties than the traditional surfactants are one of them. [30][31][32][33][34][35][36] Herein we had designed salicylate based IL (Figure 1a), cetylpyridinium salicylate (CetPySal) that show better surface active and micellar properties than its precursor surfactant cetylpyridinium chloride (CPCl) and exhibited temperature responsive gel-to-gel phase transition. The cationic precursors of the CetPySal, CPCl is known for the antiseptic and antibacterial activity as well as have applications in various fields including mouthwashes, toothpastes and in various pharmaceutical formulations among others.…”

Sodium Salicylate Mediated Ionic Liquid Based Catanionic Coacervates as Membrane‐Free Microreactors for the Selective Sequestration of Dyes and Curcumin

“…The experimental SANS data were best fitted to the spherically‐shaped aggregates with the radius smaller than that of the cylindrically‐shaped aggregates and spherically‐shaped aggregates with 200 and 400 mM concentration of the NaSal (Table ). It implies that at higher concentration of the additives, the aggregates get dis‐integrated and the size of the aggregate diminishes with changing the shape of aggregates from cylindrical‐to‐spherical shape aggregates . The measurement of the length of the cylinder was limited by the Q min of the SANS instrument.…”

Can the Isothermal Calorimetric Curve Shapes Suggest the Structural Changes in Micellar Aggregates?

“…It has been experimentally proved that aggregates can adopt different geometrical shapes, e.g., spheroids, rods, disks, ellipsoids. The morphology of micelles is determined by the type and structure of the surfactant, solution components, temperature, and surfactant concentration [30][31][32]. Generally, the tendency to form the simplest spherical micelles is the strongest at the lowest concentrations, above which the self-assembly process starts.…”