Adsorption of SARS-CoV-2 Spike Protein S1 at Oxide Surfaces Studied by High-Speed Atomic Force Microscopy

The ongoing coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents a serious threat to the health of millions of people. Respiratory viruses such as SARS-CoV-2 can be transmitted via airborne and fomite routes. The latter requires virion adsorption at abiotic surfaces and most likely involves the SARS-CoV-2 spike protein subunit 1 (S1), which is the outermost point of its envelope. Understanding S1 spike protein interaction with fomite surfaces thus represents an important milestone on the road to fighting the spread of COVID-19.*

In the article “Adsorption of SARS-CoV-2 Spike Protein S1 at Oxide Surfaces Studied by High-Speed Atomic Force Microscopy “ Yang Xin, Guido Grundmeier and Adrian Keller describe how high-speed atomic force microscopy (HS-AFM) is used to monitor the adsorption of the SARS-CoV-2 spike protein S1 at Al2O3(0001) and TiO2(100) surfaces in situ. *

NanoWorld Ultra-Short Cantilevers of the USC-F0.3-k0.3 AFM probe type were used for the high-speed atomic force microscopy. *

Figure 2 from Yang Xin et al Adsorption of SARS-CoV-2 Spike Protein S1 at Oxide Surfaces Studied by High-Speed Atomic Force Microscopy HS-AFM images (1 × 1 μm2) of SARS-CoV-2 spike protein S1 in 10 mM Tris (pH 7.5) adsorbed to a) an Al2O3(0001) and b) a TiO2(100) surface recorded at different time points as indicated. Height scales are 5 nm for the clean substrate surfaces at 0 s and 12 nm for the protein covered surfaces at later time points. Below the HS-AFM images, the corresponding height distribution functions are depicted. The vertical lines in the plots represent the height thresholds applied in the statistical analyses. NanoWorld Ultra-Short Cantilevers of the USC-F0.3-k0.3 AFM probe type were used for the high-speed atomic force microscopy.
Figure 2 from Yang Xin et al Adsorption of SARS-CoV-2 Spike Protein S1 at Oxide Surfaces Studied by High-Speed Atomic Force Microscopy
HS-AFM images (1 × 1 μm2) of SARS-CoV-2 spike protein S1 in 10 mM Tris (pH 7.5) adsorbed to a) an Al2O3(0001) and b) a TiO2(100) surface recorded at different time points as indicated. Height scales are 5 nm for the clean substrate surfaces at 0 s and 12 nm for the protein covered surfaces at later time points. Below the HS-AFM images, the corresponding height distribution functions are depicted. The vertical lines in the plots represent the height thresholds applied in the statistical analyses.

*Yang Xin, Guido Grundmeier, Adrian Keller
Adsorption of SARS-CoV-2 Spike Protein S1 at Oxide Surfaces Studied by High-Speed Atomic Force Microscopy
Advanced NanoBioMed Research, Volume 1, Issue 2, February 2021, 2000024
DOI: https://doi.org/10.1002/anbr.202000024

Open Access : The article “Adsorption of SARS-CoV-2 Spike Protein S1 at Oxide Surfaces Studied by High-Speed Atomic Force Microscopy” by Yang Xin, Guido Grundmeier and Adrian Keller is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/.

Influence of B/N co-doping on electrical and photoluminescence properties of CVD grown homoepitaxial diamond films

Boron doped diamond (BDD) has great potential in electrical, and electrochemical sensing applications. The growth parameters, substrates, and synthesis method play a vital role in the preparation of semiconducting BDD to metallic BDD. Doping of other elements along with boron (B) into diamond demonstrated improved efficacy of B doping and exceptional properties.*

In the article “Influence of B/N co-doping on electrical and photoluminescence properties of CVD grown homoepitaxial diamond films” Srinivasu Kunuku, Mateusz Ficek, Aleksandra Wieloszynska, Magdalena Tamulewicz-Szwajkowska, Krzysztof Gajewski, Miroslaw Sawczak, Aneta Lewkowicz, Jacek Ryl, Tedor Gotszalk and Robert Bogdanowicz describe how B and nitrogen (N) co-doped diamond has been synthesized on single crystalline diamond (SCD) IIa and SCD Ib substrates in a microwave plasma-assisted chemical vapor deposition process.*

The surface topography of the CVD diamond layers was investigated using atomic force microscopy (AFM), and Kelvin probe force microscopy (KPFM) was employed to measure the contact potential difference (CPD) to calculate the work function of these CVD diamond layers.*

Atomic force microscopy topography depicted the flat and smooth surface with low surface roughness for low B doping, whereas surface features like hillock structures and un-epitaxial diamond crystals with high surface roughness were observed for high B doping concentrations. KPFM measurements revealed that the work function (4.74–4.94 eV) has not varied significantly for CVD diamond synthesized with different B/C concentrations.*

NanoWorld ARROW-EFM conductive platinumirdidium5 coated AFM probes with a typical spring constant of 2.8 N/m and a typical resonant frequency of 75 kHz were used.*

Figure 2 from “Influence of B/N co-doping on electrical and photoluminescence properties of CVD grown homoepitaxial diamond films “ by Srinivasu Kunuku et al: AFM topography of B/N co-doped CVD diamond on (with fixed N/C = 0.02) SCD IIa; (a) B/C ∼ 2500 ppm (b) B/C ∼ 5000 ppm (c) B/C ∼ 7500 ppm, and KPFM CPD images of B/N co-doped CVD diamond (with fixed N/C = 0.02) on SCD IIa; (d) B/C ∼ 2500 ppm (e) B/C ∼ 5000 ppm (f) B/C ∼ 7500 ppm. NanoWorld Arrow-EFM platinumiridium coated AFM probes were used for the KPFM and surface topography measurements.
Figure 2 from “Influence of B/N co-doping on electrical and photoluminescence properties of CVD grown homoepitaxial diamond films “ by Srinivasu Kunuku et al:
AFM topography of B/N co-doped CVD diamond on (with fixed N/C = 0.02) SCD IIa; (a) B/C ∼ 2500 ppm (b) B/C ∼ 5000 ppm (c) B/C ∼ 7500 ppm, and KPFM CPD images of B/N co-doped CVD diamond (with fixed N/C = 0.02) on SCD IIa; (d) B/C ∼ 2500 ppm (e) B/C ∼ 5000 ppm (f) B/C ∼ 7500 ppm.

*Srinivasu Kunuku, Mateusz Ficek, Aleksandra Wieloszynska, Magdalena Tamulewicz-Szwajkowska, Krzysztof Gajewski, Miroslaw Sawczak, Aneta Lewkowicz, Jacek Ryl, Tedor Gotszalk and Robert Bogdanowicz
Influence of B/N co-doping on electrical and photoluminescence properties of CVD grown homoepitaxial diamond films
Nanotechnology (2022),  33 125603
DOI: https://doi.org/10.1088/1361-6528/ac4130

Please follow this external link to read the full article: https://doi.org/10.1088/1361-6528/ac4130

Open Access The article “Influence of B/N co-doping on electrical and photoluminescence properties of CVD grown homoepitaxial diamond films” by Srinivasu Kunuku, Mateusz Ficek, Aleksandra Wieloszynska, Magdalena Tamulewicz-Szwajkowska, Krzysztof Gajewski, Miroslaw Sawczak, Aneta Lewkowicz, Jacek Ryl, Tedor Gotszalk and Robert Bogdanowicz is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

Piezoelectricity of green carp scales

Today is Children’s Day in Japan and many mulit-colored carp-shaped koinobori streamers are fluttering in the wind.

So it is the perfect day to repost and share the publication “Piezoelectricity of green carp scales” by Y. Jiang et al. with you.

Piezoelectricity takes part in multiple important functions and processes in biomaterials often vital to the survival of organisms. In their publication , “Piezoelectricity of green carp scales” Y. Jiang et al. investigate the piezoelectric properties of fish scales of green carp by directly examining their morphology at nanometer levels. From the clear distinctions between the composition of the inner and outer surfaces of the scales that could be found, the authors identified the piezoelectricity to originate from the presence of hydroxyapatite which only exists on the surface of the fish scales.*

koinobori - carp streamers on children's day in Matsumoto Japan
koinobori – carp streamers on children’s day in Matsumoto Japan

These findings reveal a different mechanism of how green carp are sensitive to their surroundings and should be helpful to studies related to the electromechanical properties of marine life and the development of bio-inspired materials. As easily accessible natural polymers, fish scales can be employed as highly sensitive piezoelectric materials in high sensitive and high speed devices as well as be exploited for invasive diagnostics and other biomedical implications.*

For the harmonic responses of both 1st order and 2nd order described in this publication, NanoWorld Arrow-CONTPt AFM probes were used.

FIG. 6 from “Piezoelectricity of green carp scales “ by H. Y. Jiang et al.: First and second harmonic responses of (a) domain I and (b) domain IV. The straight line fitting for the amplitude of first harmonic response of (c) domain I and (d) domain IV by applying a series of bias. NanoWorld Arrow-CONTPt AFM probes were used.
FIG. 6 from “Piezoelectricity of green carp scales “ by H. Y. Jiang et al.: First and second harmonic responses of (a) domain I and (b) domain IV. The straight line fitting for the amplitude of first harmonic response of (c) domain I and (d) domain IV by applying a series of bias.

*Y. Jiang, F. Yen, C. W. Huang, R. B. Mei, and L. Chen
Piezoelectricity of green carp scales
AIP Advances 7, 045215 (2017)
DOI: https://doi.org/10.1063/1.4979503

Please follow this external link to access the full article: https://aip.scitation.org/doi/full/10.1063/1.4979503

Open Access The article “Piezoelectricity of green carp scales” by Y. Jiang, F. Yen, C. W. Huang, R. B. Mei and L. Chen is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.