Application of scanning electron microscopy and X-ray microanalysis: FE-SEM, ESEM-EDS, and EDS mapping for studying the characteristics of topographical microstructure and elemental mapping of human cardiac calcified deposition

Abstract

To explore the pathogenic mineral formation in a huge cardiolith isolated from the left heart atrium of an 80-year-old male patient, field emission scanning electron microscopy (FE-SEM) was used to analyze the topographic microstructure and perform elemental mapping in a cross-section of the cardiac calcified deposit after dissection. Environmental SEM equipped with an energy dispersive X-ray spectrometer (EDS) was also used to investigate the composition and spatial distribution of elements in the cross-section, and fiberoptic Raman spectroscopy was used to reidentify the chemical composition of designated positions. The results indicated that calcium hydroxyapatite and cholesterol were the main components of the cardiac calculus. The plate-like structures of calcium hydroxyapatite were unevenly spread over the cholesterol of the cardiac calculus. The calcium hydroxyapatite-rich area exhibited higher amounts of C, O, P, and Ca elements as well as trace amounts of N, Na, Mg, and Al, whereas the major concentration of C, minor concentrations of N and O, and trace amounts of P and Ca were observed in the cholesterol-rich area. Hypercholesterolemia associated with calcification of this cardiac calculus was proposed. Both FE-SEM and ESEM energy dispersive X-ray microanalyses were performed directly, for the first time, to provide useful information on the microstructural characteristics and spatial distribution of elements on the surface of human cardiac calculi.

The Comparison between the Osteogenic Differentiation Potential of Clay-Polyacrylonitrile Nanocomposite Scaffold and Graphene-Polyacrylonitrile Scaffold in Human Mesenchymal Stem Cells

“…For evaluation of calcium deposited amount and other elements in the scaffold-seeded stem cells, the samples were examined by scanning electron microscopy (SEM, JSM-7600F; JEOL Ltd., Tokyo, Japan) with energy-dispersive X-ray spectroscopy (EDS) (JEOL Ltd., Tokyo, Japan) to perform EDS mapping at days 7 and 21. EDS can make images known as digital mapping, which are compositional map of the samples [19].…”

Overview about the localization of nanoparticles in tissue and cellular context by different imaging techniques

“…Chemically or cryo-fixed tissue sections are often sputter-coated, i.e., covered with a thin layer of conductive material, for example, gold [ 176 ], to enhance the electrical conductivity of the specimen [ 177 ]. As an alternative, no coating of the specimen is required when working with low-voltage SEM setups [ 178 ]. High resolution SEM with a spatial resolution down to 1.3 nm [ 179 ] provides 3D images of nanoscale materials within biological specimens [ 20 ].…”

ESEM-EDS: In vivo characterization of the Ni hyperaccumulator Noccaea caerulescens

“…Nowadays, direct and rapid analysis of non-conductive and uncoated dry samples as well as fresh hydrated specimens can be performed using the environmental scanning electron microscopy (ESEM) technique, operating in low vacuum or wet modes (Donald, 2003). As a consequence, ESEM microscopy is increasingly exploited in many research fields, especially concerning food, medical and biological applications, with the possibility to carry out also dynamic experiments (Chang et al, 2014;Dudkiewicz et al, 2011;James, 2009;McGregor and Donald, 2010;Muscariello et al, 2005;Sorbo et al, 2008;Stabentheiner et al, 2010). The water vapor environment inside the chamber in wet mode conditions permits to perform in vivo analysis of plant tissues, while maintaining original microstructure and minimizing sample dehydration during the imaging process.…”