Structural Characterization of Perpendicularly Aligned Submicrometer-Thick Synthetic Glycolipid Polycrystalline Films Using Conventional X-ray Diffraction

Abstract

Abstract:The structural analysis of the synthetic glycolipid crystalline phase has been performed during the past few decades; however, it has not been sufficiently understood in terms of both static and dynamic aspects. We have recently shown that grazing incidence X-ray diffraction (GIXD) affords better information than conventional powder X-ray diffraction (PXRD) for the crystal structure analysis of octyl β-D-galactoside (MOβGal) using sub-micrometer-thick crystalline films and a two-dimensional detector, together with a synchrotron radiation source. However, access to this technique is not universal because of the limited machine time at the required synchrotron radiation sources. Herein, we employed XRD analysis on MOβGal hemihydrate crystalline films using commercial X-ray sources instead of synchrotron radiation sources to extend the availability of the methodology. We investigated some technical aspects of the methodology, such as incident angle and radiation time, using MOβGal polycrystalline films with different thicknesses in order to obtain sufficient reciprocal data for identifying the lattice constants with conventional X-ray sources. Complementary uses of GIXD with a two-dimensional detector, with much higher incident angles than the total reflection angle using a NANO-Viewer system and out-of-plane and in-plane measurements using SmartLab, enabled us to determine the complete lattice parameters for the MOβGal hemihydrate crystalline film.

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

“…Hence, we considered two possibilities: (i) If β-OGlu forms a crystal structure possessing the commonly reported lattice-constant relation a (≈ bilayer thickness) >> c > b, then there are at least two kinds of crystals. (ii) If β-OGlu forms an unusual crystal possessing the specific lattice-constant condition a ≈ c ≈ bilayer thickness, as recently reported for the β-OGal hemihydrate crystal [36,37], then a unique single-crystal-type structure must exist. A PXRD profile of a modulated structure of a biomembrane composite produces several diffraction patterns for a single LC arrangement [39,40].…”

“…Recently, an exclusive example from among the vast repertoire of crystal structures has been claimed for octyl β-D-galactoside (β-OGal) hemihydrate, an analogue compound of β-OGlu. The crystal structure and phase behavior have been studied effectively by grazing-incidence, wide-angle, X-ray-diffraction (GI-WAXD) analysis [36,37]. By employing GI-WAXD analysis with a two-dimensional detector (2D-GI-WAXD) and using a highly aligned, polycrystalline, sub-µm-thick, glycolipid film assembled on a substrate, the crystal structure of β-OGal hemihydrate was shown to have an intermediated ribbon-type crystal structure; this could not have been determined using single-crystal structural analysis.…”

Thermal Behavior of Anhydrous Ascorbic Acid 6‐Palmitate with Trace of Decomposition

“…The use of perpendicularly aligned sample films and a two-dimensional detector for the GI-WAXD analysis afforded in-depth insights into the phase behaviors of amphiphilic lipids in their bulk states. [20][21][22]…”

Self-organisation and characterisation of hierarchical structures in trimethyl β-cyclodextrin nano-films

“…The use of synchrotron radiation can readily overcome the difficulties caused by the low power of conventional X-ray sources. 52 In each case, the appropriate adaptation or combination of these various X-ray analytical techniques can deepen our understanding of molecular assembly and organisation behaviours not only for amorphous samples but also for crystalline samples. Therefore, we applied XRR ( Fig.…”