Identifying Nanotoxicity at the Cellular Level Using Electron Microscopy
Suresh C. Pillai, Yvonne Lang in Toxicity of Nanomaterials, 2019
SEM and TEM are the key enabling technologies that provide adequate resolution for nanoparticle visualisation. Although the chemical nature and subsequent electron contrast of specific nanoparticles may restrict visualisation to higher atomic number particles, elemental analysis techniques such as energy dispersive spectroscopy or electron energy loss spectroscopy provide data on the distribution of particles of low atomic number. It is important to consider the small volume of tissue that can be imaged via EM, in particular typical TEM section thickness of 50–70 nm. The use of three-dimensional reconstruction techniques such as ET and the SBF sectioning methods have greatly expanded imaging potential and offer new possibilities in the field of intracellular nanoparticle localisation research (Denk and Horstmann, 2004). A caveat on these approaches is that, despite providing detailed ultrastructure, they are time-consuming and result in huge datasets on limited sample sizes, which rightly raises concerns regarding sampling bias.
A ‘Biomaterial Cookbook’: Biochemically Patterned Substrate to Promote and Control Vascularisation in Vitro and in Vivo
Harishkumar Madhyastha, Durgesh Nandini Chauhan in Nanopharmaceuticals in Regenerative Medicine, 2022
Myriad analytical techniques are now available for supporting the development of biomaterial scaffolds. Techniques for probing the chemistry in bulk include gel permeation or gas chromatography, Fourier transform infrared and Raman spectroscopy, nuclear magnetic resonance (Pradhan, Rajamani, Agrawal, Dash, & Samal, 2017), whereas the analysis of surface chemistry employs time of flight secondary ionisation mass spectrometry, X-ray photoelectron spectroscopy, matrix-assisted laser desorption electrospray ionisation time of flight and infrared matrix-assisted laser desorption electrospray ionisation mass spectrometry, and energy-dispersive X-ray spectroscopy (Kingshott, Andersson, McArthur, & Griesser, 2011). Bulk morphological properties are probed via dynamic light scattering, X-ray and neutron scattering, X-ray diffraction (Bose & Bandyopadhyay, 2013), and scanning confocal fluorescence microscopy, whereas surface topology is typically probed high-resolution of scanning and transmission electron microscopy (SEM and TEM) and laser scanning microscopy (Merrett, Cornelius, McClung, Unsworth, & Sheardown, 2002). Currently, cell response is evaluated via immunohistochemical staining, SEM imaging, and gene expression assays to evaluate cell viability, proliferation, differentiation, and angiogenic activity (Łopacińska et al., 2012). The collective work suggests promise for 3D engineered hydrogels with controlled heterogeneity and controlled cell behaviour.
IBS™ bioresorbable scaffold by Lifetech
Yoshinobu Onuma, Patrick W.J.C. Serruys in Bioresorbable Scaffolds, 2017
Accordingly, the possible corrosion products of iron scaffold in vivo are Fe3O4 and Fe2O3 (in original strut position), Fe3(PO4)2, and FeOOH (both precipitated in tissue round struts). The theoretical analysis above has been verified by tests of the explanted in vivo specimen of IBS using energy dispersive spectrometer (EDS), X-ray photoelectron-spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM), infrared spectrometer (IR spectrometer), and Raman photography.
Sageretia thea (Osbeck.) modulated biosynthesis of NiO nanoparticles and their in vitro pharmacognostic, antioxidant and cytotoxic potential
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Ali Talha Khalil, Muhammad Ovais, Ikram Ullah, Muhammad Ali, Zabta Khan Shinwari, Dilawar Hassan, Malik Maaza
For the detection of any other surface interface-bounded compounds, ATR-FTIR over the spectral range (4000 cm−1 to 400 cm−1) was carried out as indicated in Figure 4(A). The strong absorption observed at ∼418 cm−1 is attributed to the Ni-O vibration in stretching mode [8] while the broad absorption band observed nearly at 3300 cm−1 can be attributed to the adhered –OH functional groups. The FTIR spectrum was consistent with XRD results as no impurities are indicated. To further confirm nickel oxide nanoparticles, Raman spectrum was recorded in the spectral range of 0 cm−1 to 2000 cm−1 as indicated in Figure 4(B). Generally, Raman spectra from NiO have contributions from one phonon LO and TO modes, two phonon excitation and one, two and four magnon excitations. In a case where NiO is anti-ferromagnetically ordered or defect rich, then a significant increase in one phonon scattering [8]. Various characteristic Raman peaks can be observed positioned at ∼390 cm−1 (1 P), ∼652 cm−1 (2 P), ∼771 cm−1 (2 P), ∼1064 cm−1 (2 P) and ∼1660 cm−1 (2 M). These peaks are consistent with the earlier reported Raman spectra [38]. Figure 5 presents the EDS spectra to investigate the elemental components of the sample. Energy-dispersive spectroscopy was carried out for the elemental analysis. Peaks from “Ni” and “O” are evident confirming Ni-O in the sample, while peak indicating “C” is attributed to the grid support.
Scanning electron microscopy in analysis of urinary stones
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2019
Martin Racek, Jaroslav Racek, Ivana Hupáková
Chemical characteristics of materials including kidney stones can be also achieved with X-ray spectroscopy analytical methods. The use of these methods requires primary irradiation of the sample, which leads to ejection of electrons from the sample atoms. The resulting unstable state leads to an effect where the hole is filled by an electron from a higher orbital. The difference of the energy is balanced by a release of a photon with energy/wavelength characteristic for a given element. The characteristic X-rays emission can be reached in various ways, which is determinative for each method. The sample may be irradiated by high-energy protons (PIXE [47,48]), high-energy electrons (coupled with SEM, [29,35,38]) or primary X-rays (XRF [47–50]). The emitted X-rays can then be characterized based on their energy (energy-dispersive spectroscopy [EDS]) or wavelength (wavelength-dispersive spectroscopy [WDS]).
Green synthesis of silver nanoparticles using transgenic Nicotiana tabacum callus culture expressing silicatein gene from marine sponge Latrunculia oparinae
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Yuri N. Shkryl, Galina N. Veremeichik, Dmitriy G. Kamenev, Tatiana Y. Gorpenchenko, Yulia A. Yugay, Dmitriy V. Mashtalyar, Aleksander V. Nepomnyaschiy, Tatiana V. Avramenko, Aleksandr A. Karabtsov, Vladimir V. Ivanov, Victor P. Bulgakov, Sergey V. Gnedenkov, Yury N. Kulchin, Yury N. Zhuravlev
The morphology of the synthesized silver nanoparticles was characterized by scanning electron microscopy (SEM) using Hitachi S-5500 (Japan) at the accelerating voltage of 2.0 kV. The local energy-dispersive spectroscopy (EDS) data were obtained on a Thermo Scientific (USA) spectrometer. Purified nanoparticles were also characterized using an atomic-force microscopy (AFM) using a Pacific Nanotechnology, Inc. Nano-DST (USA). A small volume of sample was spread on a well-cleaned glass cover slip surface mounted on the AFM stub and was dried in vacuum at room temperature. Images were obtained in tapping mode using a silicon probe cantilever of 225 μm length, resonance frequency 145–230 kHz, spring constant 20–95 N/m. Hydrodynamic diameter and zeta potential of the obtained nanoparticles were measured by nanoparticle tracking analysis (NTA) using a Nanosight NS500 system (NanoSight, UK) following the manufacturer’s instructions. Samples were diluted with water to obtain approximately 20 particles per image before being analysed with the NTA system. The measurements were made at room temperature and 60 s capture of video clips of particle movement under Brownian motion. The captured videos (10 videos per sample) were then processed and analysed by NTA analytical software version 2.2. For zeta potential estimation, the script for video recording and analysis designed by the manufacturer was employed.
Related Knowledge Centers
- Elemental Analysis
- X-Ray
- Atom
- Emission Spectrum
- Spectroscopy
- Moseley'S Law
- X-Ray Detector
- Electron Microscope
- Scanning Electron Microscope
- Scanning Transmission Electron Microscopy