Application of Synchrotron Radiation Technology in Marine Biochemistry and Food Science Studies
Se-Kwon Kim in Marine Biochemistry, 2023
The structure and distribution of the components, such as protein, lipid, and water, of the edible parts of fish are known to influence food qualities, including texture, stability, freshness, taste, sensory properties, and bacterial contamination (Schoeman et al. 2016; Alasalvar et al. 2011; Nakazawa and Okazaki 2017; Nakano 2019). Therefore, there is a need to develop a nondestructive and noninvasive observation method with which to evaluate and understand the structure and distribution of food components in order to produce high-quality products. Techniques used to observe the inner structure (microstructure) of food require destructive sample preparation or are limited to specific applications, such as electron microscopy and magnetic resonance imaging (MRI) (Schoeman et al. 2016). The applications of SR-based techniques in food science are summarized in Table 2.1. SR-based XRCT is an innovative radiographic imaging technology that enables both the nondestructive and the noninvasive 3D imaging of the microstructure of food at high resolutions (Schoeman et al. 2016). XRCT is known to visualize the content and distribution of muscle, bones, fat, and rind of meat (Miklos et al. 2015; Jensen et al. 2011). SAXS is used to obtain structural information, such as the size and shape distribution, of a material by analyzing the scattering vector of X-rays. One example of food analysis using SAXS is the nanostructure analysis of dairy products. Nanostructure analysis of dairy products (Nasuda et al. 2020), casein (Marchin et al. 2007), and the quality of meat (Hoban et al. 2016) have been conducted using SAXS or ultrasmall-angle XS. Casein micelles, which play a major role in the aggregation process of cheese, are distributed over a relatively wide size range (20‒600 nm in diameter), with an average diameter of approximately 100 nm (Marchin et al. 2007). Although transmission electron microscope (TEM), including cryo-TEM, is necessary to observe the structure of these micelles, samples must be dried and frozen, which is problematic due to the fact that they differ greatly from the original state of the food (Aoki et al. 2017). On the other hand, SAXS can be used at room temperature and pressure to obtain nano-level structural information under conditions close to those of the original food. Using SAXS measurements to analyze cheese, the differences in the chainlike structure of milk fat and the formation of particles of approximately 6‒17 nm, depending on the aging period of the cheese, have been reported (Nasuda et al. 2020). XRCT and SAXS are not unique to SR. It is possible to measure XRCT and SAXS using laboratory-level equipment. We demonstrate the advantages of using SR-based X-rays to measure both SAXS and CT images.
Profiling of drug crystallization in the skin
Published in Expert Opinion on Drug Delivery, 2020
Choon Fu Goh, Ben J. Boyd, Duncan Q. M. Craig, Majella E. Lane
In the present work, we used X-ray scattering or diffraction (XRD) to investigate detection of drug crystals formed in situ in the deeper layers of the skin, after application of preparations with high drug thermodynamic activity. Both small-angle (SAXS) and wide-angle (WAXS) X-ray scattering were used because SAXS and WAXS can be measured at the same time but generate different X-ray scattering profiles depending on the diffraction angles. SAXS is also of particular benefit when examining large structural units (structural features with large repeat distances) in a sample. This is especially useful when studying skin components such as lipid lamellar phases in the SC or collagen in the dermis. On the other hand, substances with smaller structural units such as drug crystals demonstrate diffraction at a larger angle in the WAXS profiles. This unique characteristic should enable detection and differentiation of the X-ray scattering by drug crystals from the skin components.
Updated insight into the characterization of nano-emulsions
Published in Expert Opinion on Drug Delivery, 2023
Xinyue Wang, Halina Anton, Thierry Vandamme, Nicolas Anton
SAXS and small-angle neutron scattering (SANS) are scattering techniques based on the diffraction (normally with an angle between 2° and 5°) of electrons or protons beam due to the difference in electron cloud density between the sample and surrounding medium. Small-angle scattering techniques are useful for studying the structure and interactions of complex fluids and colloids, allowing the determination of form factors: particle size, surface area, and particle shape in concentrated solutions [77–80]. This technique also evidences the structure factor – which allows calculating the interactions in the system.
Small-angle X-ray scattering for the proteomics community: current overview and future potential
Published in Expert Review of Proteomics, 2021
SAXS is a method to gain information on the size and shape of particles, by way of exposing the sample to an X-ray beam and measuring the resulting scattering of X-rays from the sample as a function of scattering angle. SAXS data can provide both complementary and unique information on the behavior of the sample under study. Hence, it is an integral part of a regular structural biology workflow.
Related Knowledge Centers
- Colloid
- Crystallography
- Macromolecule
- Micelle
- Protein
- Liposome
- Small-Angle Neutron Scattering
- X-Ray
- X-Ray Scattering Techniques
- Polymersome