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Inorganic Particulates in Human Lung: Relationship to the Inflammatory Response
Published in William S. Lynn, Inflammatory Cells and Lung Disease, 2019
Victor L. Roggli, J. P. Mastin, John D. Shelburne, Michael Roe, Arnold R. Brody
For many inorganic particulates, elemental composition is not sufficient for complete, accurate mineralogical characterization. In these instances, information about the crystalline structure of the material is required. Two techniques have been used in the study of inorganic particulates to obtain crystallographic data: X-ray diffraction, which is a bulk technique, and selected area electron diffraction, a microanalytical technique which permits analysis of individual microscopic particles and which may be performed on most modern transmission electron microscopes.12, 14 The diffraction of X-rays or electrons as they pass through the sample produces a characteristic pattern which may be recorded on photographic film, and the geometric and dimensional information obtained can then be related to the crystal structure through Bragg’s law. The diffraction patterns for thousands of known standard materials have been catalogued in the A.S.T.M. (American Society for Testing Materials) index. X-ray diffraction and selected area electron diffraction have been used fairly extensively in the study of inorganic particulates extracted from lung tissues.6, 24–30 In addition, X-ray diffraction may be used in the quantitative determination of mineral species (e.g., quartz31 and asbestos32).
Electron Spectroscopy For Chemical Analysis: Applications in the Biomedical Sciences
Published in R. Michael Gendreau, Spectroscopy in the Biomedical Sciences, 1986
Buddy. D. Ratner, Brien. J. McElroy
The X-ray monochromator crystal is used to remove the unwanted satellites and background radiation at the same time improving the width of the desired line. Typically, A1 Kα X-rays are diffracted by a quartz crystal by Bragg’s law:
Neuro-protective effects of nano-formulated hesperetin in a traumatic brain injury model of Danio rerio
Published in Drug and Chemical Toxicology, 2022
Pragyan Paramita, Sai Nivethitha Sethu, Namasivayam Subhapradha, Vijayashree Ragavan, Ramachandran Ilangovan, Anandan Balakrishnan, Narasimhan Srinivasan, Ramachandran Murugesan, Ambigapathi Moorthi
The surface topography and size of the nHST particle was analyzed using scanning electron microscopy (SEM) and dynamic light scattering (DLS) method. The sample was sputter coated onto platinum and the scanning at 25 kV and 40 mA under vacuum for SEM analysis. The particle size distribution of nHST particle was confirmed using particle size analyzer. The principle beyond in particle size measurement is based on measuring time dependent fluctuation of scattering of laser light by the nHST particle. The functional groups present in the HST and nHST particles were determined by FT-IR analysis using KBr press. The spectra were collected over the range of 4000–500 cm−1. The spectrograms of the samples were plotted using OPUS software. XRD patterns for HST and nHST were obtained using a pan-analytical XPERTPRO powder diffractometer with an operational voltage of 40 kV and CuKα radiation (1.54 Å) at room temperature. The samples were analyzed in a continuous mode with 0.01° step size, 1 s stem time and an angular range of 3–40° 2θ. The intensity of the diffracted pattern was calculated using Bragg’s law with the formula: nλ = 2dsinθ.
Analysis of elements secreted by CHO-K1 cells exposed to gamma radiation under different treatments
Published in International Journal of Radiation Biology, 2020
Joanna Czub, Janusz Braziewicz, Aldona Kubala-Kukuś, Andrzej Wójcik
The WD-XRF is the method used to determine the concentration of elements in a tested material (Baedecker 1987). This method was described earlier by Bielecka et al. (2014), Banaś et al. (2019), hence here only a brief description. In the WD-XRF method, similarly as in the TXRF method, a photoelectric effect is used where X-ray fluorescent radiation is emitted from the tested material as a result of inducing it by falling X-ray radiation. Fluorescent radiation is characteristic for a given element being a component of the tested material. Fluorescent radiation emitted here is, in contrast to the TXRF method, recorded in a wavelength dispersion system. In such a fluorescence radiation recording system, an package of analyzing crystals are used which work by reflecting the wavelength radiation that meets the Bragg’s law. The detector system then registers the reflected radiation. Quantitative and qualitative elemental analysis is carried out on the basis of registered fluorescent radiation (Willis and Duncan 2008). The WD-XRF method is a technique that underlies the commercially available AXIOS Max X-ray spectrometer (PANalytical, Netherlands) that was used in this research. This spectrometer is equipped with an X-ray tube (rhodium (Rh) anode, 2.4 kW power) that emits X-ray radiation which falls on the tested material, five analyzing crystals (LiF (200), Ge (111), PE (002), PX1, LiF (220)) that provide radiation analysis over a wide range of wavelengths and a radiation detection system consisting of a flow detector and a scintillation detector (Axios 2019).
Nano-gold displayed anti-inflammatory property via NF-kB pathways by suppressing COX-2 activity
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Mahmood Ahmad Khan, Mohd Jahir Khan
Figure 2(A) shows XRD pattern of AuNGs. The main diffraction peaks 2θ appears at 38°, 44.25°, 64.5° and 77.5° in which Bragg’s law correspond to the planes are (111), (200), (220) and (311), respectively. These peaks are the characteristics and in good agreement with the standard XRD peaks of AuNGs as reported in previous studies (JCPDS-040784) [41,42]. DLS measurements were performed to further investigate size and polydispersity of AuNGs (Figure 2(B)). The hydrodynamic radii of AuNGs was increased slightly due aggregation in the medium and it was recorded ∼20 nm. The shape and size of AuNGs was further examined by TEM as shown in Figure 2(C). TEM images of AuNGs clearly show isolated particles with ∼15 nm in size. The average diameter of AuNGs was calculated by measuring several particles in random fields of TEM view demonstrated that most of the NPs were spherical in shape.