Anhydrous octyl-glucoside phase transition from lamellar to isotropic induced by electric and magnetic fields

Abstract

A static deuterium nuclear magnetic resonance (HNMR) technique (magnetic field, B = 7.05 T) was employed to monitor the thermotropic lamellar phase of the anhydrous 1:1 mixture sample of octyl-b-D-glucoside (βOG) and that of partially deuterium labelled at the alpha position on the chain, i.e.,βOG-d In the absence of an electric field, the H NMR spectrum of the mixture gives a typical quadrupolar doublet representing the aligned lamellar phase. Upon heating to beyond the clearing temperature at 112 °C, this splitting converts to a single line expected for an isotropic phase. Simultaneous application of magnetic and electric fields (E = 0.4 MV/m) at 85 °C in the lamellar phase, whose direction was set to be parallel or perpendicular to the magnetic field, resulted in the change of the doublet into a single line and this recovers to the initial doublet with time for both experimental geometries. This implies E- and B-field-induced phase transitions from the lamellar to an isotropic phase and a recovery to the lamellar phase again with time. Moreover, these phase transformations are accompanied by a transient current. A similar observation was made in a computational study when an electric field was applied to a water cluster system. Increasing the field strength distorts the water cluster and weakens its hydrogen bonds leading to a structural breakdown beyond a threshold field-strength. Therefore, we suggest the observed field-induced transition is likely due to a structure change of the βOG lamellar assembly caused by the field effect and not due to Joule heating.

Unveiling the Uniqueness of Crystal Structure and Crystalline Phase Behavior of Anhydrous Octyl β-D-Glucoside Using Aligned Assembly on a Surface

“…Immiscible solutions consisting of high-and low-concentration solutions of β-OGlu have been exploited for membrane protein purification [2]. The glass-transition behavior both in the absence and presence of ice, and the water-cluster-like responsive behavior under magnetic and electric fields have been demonstrated for the LC phases [23,25,26,[28][29][30]. These physical properties of β-OGlu self-assembly must be directly or indirectly related to the specific features of individual β-OGlu interactions with proteins-and/or surrounding the proteins with self-assembling membrane domains-and they may further advance its use.…”

Solution Properties of Alkyl β‐D‐Maltosides

“…However, there are not enough data and messages available to support effectively the application in the field of life and material sciences although there are some available features/parameters including critical micelle concentration (CMC) (Frotscher et al, 2017;Matsuoka et al, 2017;Santonicola et al, 2008), sugar headgroup structure (Ehsan et al, 2016), field-induced phase transition (Hashim et al, 2017), paracellular permeation (Gradauer et al, 2017), and cell metabolism (Smułek et al, 2017). The corresponding fairly accurate and feasible screening should rely heavily on the empirical evidence, exhaustive trial-and-error process and rational thinking, and even intuitive approach.…”

Dry Thermotropic Glycolipid Self-Assembly:A Review

“…However, there are numerous reports on the application of electric field on water clusters also a hydrogen bonded system with many interesting effects of biology importance 95,96 . Assuming that GL is also a form of hydrogen bonded cluster 97 , not too dissimilar from water, electric and magnetic fields have been applied to β-GlcC 8 and the effects were studied using the deuterium nuclear magnetic resonance spectroscopy DNMR 98 . Both dielectric and magnetic susceptibility anisotropies of β-GlcC 8 are negative and it has a weak birefringence 0.05 .…”