An ionic liquid-based surfactant with ester functionality self-aggregates in an aqueous medium and forms ionogels at 8.80% (w/v) concentration at physiological pH. The ionogel exhibited a remarkable change in its appearance with temperature from fibrillar opaque to transparent because of the dynamic changes within its supramolecular structure. This gel-to-gel phase transition occurs below the melting point of the solid ionic liquid. The ionogels were investigated using turbidity, differential scanning calorimetry, scanning electron microscopy (SEM), field emission SEM (FE-SEM), inverted microscopy, transmission electron microscopy imaging, Fourier transform infrared spectroscopy, and rheological measurements. The fibrillar opaque ionogel and transparent ionogel were studied for their ability to absorb dyes (methyl orange and crystal violet) and to encapsulate drugs (diclofenac sodium and imatinib mesylate).

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The motivation for designing low-molecular-weight gelators with selfhealing characteristics originates from elegant examples in biology such as vines of the genus Aristolochia whose internal secondary growth exhibits rapid self-healing in their stems. In the present work, we had explored the stimuli-responsive dual gelation characteristics for the ester-functionalized surfactant (4-(2-(hexadecyloxy)-2-oxoethyl)-4methylmorpholin-4-ium bromide, C 16 EMorphBr) in aqueous medium at 7.20% (w/v) critical gel concentration and pH 7.4. The hydrogel provides an excellent platform to study dynamic phase behavior within a supramolecular network as it exhibits transformation from a fibrillar opaque hydrogel to a transparent hydrogel upon heating. Molecular interactions, arrangement within the supramolecular framework, and mechanical properties of the hydrogels were characterized using Fourier transform infrared, small-angle neutron scattering, rheological analysis, and tensile strength and cyclic loading−unloading tests. The fibrillar opaque gel has been characterized for its morphology using scanning electron microscopy, field emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. The self-sustained, self-healable porous fibrillar opaque xerogel was further explored for selectively absorbing anionic dyes and for its load-bearing characteristics. We conclude a perspective on designing a new-age gelator that can open entirely new avenues in environmental protection and wearable "smart" devices.

Limitations associated with the traditional cancer therapies prompt the scientific community to develop an effective, safer, smarter and targeted drug carriers that improve the efficiency of the drug carrier, reduce the adverse effects of the drug on the healthy cells, and helps in preventing the cancer recurrences. This research aims to design a stimuli-responsive, self-healable, adhesive, and injectable polymeric hydrogel with ester functionalized ionic liquid (ILs) as one of the additives to improve the efficiency of the anti-cancer drug in encapsulation and localized delivery. The designed polymeric hydrogel responds to intracellular biological stimuli (e.g. acidic pH of cancerous cells and temperature), change the morphology through changing the shape and size of the gelator within the hydrogel matrix and release the encapsulated doxorubicin (DOX) at the tumor site efficiently. Molecular interactions, gel morphology, and mechanical strength of the hydrogel were characterized through various analytical techniques, including small angle neutron scattering (SANS). Adhesive properties of the polymeric hydrogel were measured by lap-shear strength tests and biocompatibility and cellular drug uptake study on human breast cancer (MCF-7) and human cervical carcinoma cells (HeLa). The in-vitro cytotoxicity and drug release study showed that the hybrid hydrogel is more effective at killing the cancerous cells, and the targeted release of the DOX occurred at intracellular acidic pH. The polymeric hydrogel provides an efficient therapeutic approach for the encapsulation and release of the drug. Overall, the study offers a proof of 2 | P a g e concept to test the feasibility of the hydrogel system whether the hydrogel formulation helped or hindered the total cellular DOX trafficking.

Conceptualising gelators with stimuli responsiveness is advantageous to design smart materials for emerging technologies. These gelators, if are surface active and made up of active pharmaceutical ingredients, can (i) exhibit an interesting pharmaceutical profile, (ii) be useful in drug formulations and (iii) exert direct effects on cell membranes. Herein, cetylpyridinium salicylate (CetPySal) that offers higher surface activity than its precursor surfactant, cetpylpyridinium chloride (CPCl), was synthesised. CetPySal forms a temperature‐responsive ionogel at a critical gelation concentration that changes its physical appearance with temperature, i. e. opaque to transparent, owing to its structural arrangement within its supramolecular framework, that are characterized through spectrometric, calorimetric, scattering and microscopic techniques. The viscoelastic nature of the ionogels was studied through dynamic rheological measurements and the interactions that governs the phase transition were studied through FTIR spectroscopy. The hybrid pharmaceutical ionogels was successfully constructed through encapsulation of the chemotherapeutic drug imatinib mesylate within the ionogel matrix. The sustained release of the drug was investigated from this hybrid ionogel matrix. These results suggest that this new thermo‐responsive ionogel may be used to improve sustained release of drugs and open up new avenues as low‐cost gelators for biomedical applications.

Stable vesicular aggregate is the primary requisite to transport and deliver the biological and pharmaceutical standards. The serendipitous discovery of nonlipid vesicles made with the nonlipid building blocks, such as ionic liquid based surfactants (ILBSs) proved to be advantageous over others. In a quest to achieve stable, more rigid and hydrophobic vesicles from ILBSs, here we have investigated the lipid (cholesterol) induced unilamellar vesicle formation in the aqueous functionalized and nonfunctionalized ILBSs. The vesicles show outstanding stability with time, temperature and dilution with water. Spectroscopic (turbidity, steady state absorbance and fluorescence), scattering (dynamic light scattering) and microscopic (transmission electron microscopy) techniques were used to characterize the vesicles. The hydration behavior and rigidity associated with the vesicular bilayer on transforming from micellar assembly was characterized through steady state absorbance and fluorescence techniques. The unilamellar vesicles derived are compared with the conventional surfactant, i. e. cetyltrimethyl ammonium bromide.[a] Dr.

Surfactant-mediated coacervates are termed as the new age microreactors for their ability to spontaneously sequester the molecules with varied polarities and functionalities. Efforts to emulate this applicability of coacervates through synthetic control of surfactant structures are finding success; however, there is little understanding of how to translate these changes into tailor-made properties. Herein, we designed 3-methyl-1-(octyloxycarbonylmethyl)imidazolium bromide (C 8 EMeImBr), an ester-functionalized ionic liquid-based surfactant, which shows better surface active properties than the nonfunctionalized and conventional cationic surfactant and forms complex coacervates over the broad range of concentration with sodium salicylate (NaSal). Mono- and divalent cations as well as ionic strength, viscosity, and time-dependent stability of the coacervates had also been addressed in order to study whether these coacervates could work as microreactors to encapsulate various molecules. The anionic charged complex coacervates with sponge morphology and honey comb-like interior show good efficiency to sequester cationic dyes from water because of electrostatic and hydrophobic interactions and good encapsulation efficiency for curcumin owing to their high surface area. Results suggest that ionic liquid-based coacervates studied here could be exploited as a novel low-cost, effective, and environmentally benign alternative to sequester dyes from the contaminated water and their recovery.

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