Micelle Structure in a Deep Eutectic Solvent for the Electrochemical Preparation of Nanomaterials

Nanostructure in Amphiphile-Based Deep Eutectic Solvents

Deep eutectic solvents (DESs) are an emerging class of modern, often "green" solvents with unique properties. Recently, a deep eutectic system based on amphiphilic surfactant N-alkyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (C12 & C14 sulfobetaine) and (1S)-(+)-10-camphor-sulfonic acid in the molar ratio 1:1.5 has been reported. Nanostructuring can be expected in this DES due to the nature of the components. In this work, we have investigated the native nanostructure in the DES comprising C12-C18 alkyl chain sulfobetaines with camphor sulfonic acid and how it interacts with polar and nonpolar species, water and dodecane, respectively, using small angle neutron scattering. By using contrast variation to highlight the relative position of the solvent components and additives, we can resolve the structure of the solvent and how it changes upon interaction with water and dodecane. Scattering from the neat DES shows structures corresponding to the self-assembly of sulfobetaines; the size of the structure increases as the alkyl chain length of the sulfobetaines increases. Water and dodecane interact, respectively, with the hydrophilic and hydrophobic moieties in the DES structure, primarily the sulfobetaine, thereby swelling and solvating the entire structure. The extent of the shift of the peak position, and the swelling, depend on concentration of the additive. The solution phase organization and the interaction of polar and nonpolar species as observed here, have the potential to affect the ordering of inorganic or polymeric materials grown in such solvents, paving new avenues for templating applications.

Electrodeposition of Silver in a Ternary Deep Eutectic Solvent and the Electrochemical Sensing Ability of the Ag-Modified Electrode for Nitrofurazone

The determination of nitrofurazone (NFZ) has received substantial attention because it is a kind of antibiotic drug. Herein, a rapid and low-cost electrochemical sensor for the analysis of NFZ is reported. The method uses Ag-modified electrodes in which different surfactants, hexadecyltrimethylammonium bromide and sodium dodecyl sulfate, in a ternary choline chloride-urea-glycerol deep eutectic solvent were deposited. The physical properties of the solutions with various surfactants are investigated by a conductivity meter, viscometer, and tensiometer. The morphologies and crystallinity of the Ag-modified electrodes were characterized by using scanning electron microscopy, transmission electron microscopy, and powder X-ray diffraction. Electrochemical impedance spectroscopy and CV analyses indicate that the as-prepared Ag-SDS electrode exhibited better performance as a NFZ sensor. The dynamic linear range of NFZ is 0.66-930 μM with a corresponding detection limit of 0.37 μM. The proposed electrochemical sensor was applied to detect NFZ in the aquaculture water sample, and the results showed good recovery in the range from 100.28 to 102.65%.

Bayesian determination of the effect of a deep eutectic solvent on the structure of lipid monolayers

A novel reflectometry analysis method reveals the structure of lipid monolayers at the air-DES interface.