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Application of Synchrotron Radiation Technology in Marine Biochemistry and Food Science Studies
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Toshiki Nakano, Masafumi Hidaka
SAXS is an analysis method that obtains structural information, such as the size and shape distribution of a material, by analyzing the scattering vector of X-rays scattered according to the structure of the material when X-rays are irradiated on it.
Factors affecting the preparation of nanocrystals: characterization, surface modifications and toxicity aspects
Published in Expert Opinion on Drug Delivery, 2023
Shirleen Miriam Marques, Lalit Kumar
Small-angle X-ray scattering (SAXS) provides a more statistically reliable estimate of the size of the nanoparticles since the particle size distribution obtained by SAXS is generally estimated over many nanoparticles. In contrast, the size distribution obtained by electron microscopy methods is derived from only a few hundred or thousand particle measurements [159–161]. Li et al. used an in-vitro digestion model together with SAXS to determine the polymorphic transformation of the nanocrystals during the digestion of the nanocrystal-encapsulated liposomes. The study revealed a complete transition of the hydrated drug nanocrystals to a different salt. It was also necessary to determine the solid state of the drug within the liposomes since it could dictate the drug release pattern from the liposomes [162].
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.
Influence of the bispecific antibody IgG subclass on T cell redirection
Published in mAbs, 2019
Stephanie Kapelski, Erna Cleiren, Ricardo M. Attar, Ulrike Philippar, Julien Häsler, Mark L. Chiu
SAXS-data were generated and analyzed at the Illinois Institute of Technology. CD19-targeting parental antibodies in the five generated IgG subclasses (IgG1, IgG2, IgG4, IgG1:2, and IgG4:2) were used as representative model antibodies for structural studies. Samples (250 μL at 12 mg/ml) were purified through a Wyatt SEC Analytical Column (5 μm, 300 Å, 7.8 mm) using an Agilent Infinity II HPLC system. After being eluted from the column, the sample passed through a multiple wavelength UV detector, followed by a DAWN HELEOS II (18 angle research grade light scattering photometer), a Wyatt QELS (Integrated into the multi-angle light scattering detector to perform simultaneous QELS (dynamic light scattering) measurements in the same flow cell or cuvette), an Optilab TrEX (Refractive Index detector for measurement of Differential and Absolute refractive index measurement) and finally to the SAXS flow cell. The beam was attenuated to 23–30% of full intensity, every 3 s for 0.5 s. The Rg value was derived from the SAXS data.58