Tag: biomaterials

Nano- and Micro-Patterned S-, H-, and X-PDMS for Cell-Based Applications: Comparison of Wettability, Roughness, and Cell-Derived Parameters

Polydimethylsiloxane (PDMS) is a promising biomaterial for generating artificial extracellular matrix (ECM) like patterned topographies, yet its hydrophobic nature limits its applicability to cell-based approaches.” Although plasma treatment can enhance the wettability of PDMS, the surface is known to recover its hydrophobicity within a few hours after exposure to air. *

To investigate the capability of a novel PDMS-type (X-PDMS) for in vitro based assessment of physiological cell properties, the authors of the article “Nano- and Micro-Patterned S-, H-, and X-PDMS for Cell-Based Applications: Comparison of Wettability, Roughness, and Cell-Derived Parameters” cited here, designed and fabricated plane as well as nano- and micrometer-scaled pillar-patterned growth substrates using the elastomer types S-, H- and X-PDMS, which were fabricated from commercially available components.*

To assess their applicability to cell-based approaches, Marina Scharin-Mehlmann et al., characterized the generated surfaces using water contact angle (WCA) measurement and atomic force microscopy (AFM) as indicators of wettability and roughness, respectively.*

The surface roughness of the samples was determined by Atomic Force Microscopy in tapping mode. For plane and flat pillar patterned PDMS (130 and 190 nm nominal pillar height) surfaces, a standard tapping mode AFM probe ( Pointprobe® NCHR, NanoWorld) was used. For patterned surfaces with pillars of 1,800 nm height tilt compensated high-aspect-ratio AFM probes (AR5T-NCHR, NanoWorld) were used. The scanning area was 50 × 50 μm2, the scanning rate 0.5 Hz. In this scanning area each roughness value (root mean square roughness Rq) was evaluated from five 10 × 10 μm2 areas.*

Figure 5 from “Nano- and Micro-Patterned S-, H-, and X-PDMS for Cell-Based Applications: Comparison of Wettability, Roughness, and Cell-Derived Parameters” by Marina Scharin-Mehlmann et al.: AFM analysis of structured PDMS substrates. (A) Three-dimensional reconstructions of fabricated pillar-structured PDMS substrates recorded by AFM. (B) Mean pillar height of plane S-, H-, and X-PDMS as measured by AFM. All data are significantly different at a significance level of P ≤ 0.001 as evaluated by two-way ANOVA unless otherwise indicated. Color coding of statistical analysis: within group “130 nm,” purple; within group “190 nm,” pink.

Figure 5 from “Nano- and Micro-Patterned S-, H-, and X-PDMS for Cell-Based Applications: Comparison of Wettability, Roughness, and Cell-Derived Parameters” by Marina Scharin-Mehlmann et al.: AFM analysis of structured PDMS substrates. (A) Three-dimensional reconstructions of fabricated pillar-structured PDMS substrates recorded by AFM. (B) Mean pillar height of plane S-, H-, and X-PDMS as measured by AFM. All data are significantly different at a significance level of P ≤ 0.001 as evaluated by two-way ANOVA unless otherwise indicated. Color coding of statistical analysis: within group “130 nm,” purple; within group “190 nm,” pink.

*Marina Scharin-Mehlmann, Aaron Häring, Mathias Rommel, Tobias Dirnecker, Oliver Friedrich, Lothar Frey and Daniel F. Gilbert
Nano- and Micro-Patterned S-, H-, and X-PDMS for Cell-Based Applications: Comparison of Wettability, Roughness, and Cell-Derived Parameters
Frontiers in Bioengineering and Biotechnology. 2018; 6: 51
DOI: 10.3389/fbioe.2018.00051

Please follow this external link to view the full article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5938557/

Open Access: The article «Nano- and Micro-Patterned S-, H-, and X-PDMS for Cell-Based Applications: Comparison of Wettability, Roughness, and Cell-Derived Parameters» by Marina Scharin-Mehlmann, Aaron Häring, Mathias Rommel, Tobias Dirnecker, Oliver Friedrich, Lothar Frey and Daniel F. Gilbert (2018) 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 will flutter in the wind.

So it is the perfect day to 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 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/.

Effective gamma-ray sterilization and characterization of conductive polypyrrole biomaterials

“Conductive polymers, including polypyrrole (PPy), have been extensively explored to fabricate electrically conductive biomaterials for bioelectrodes and tissue engineering scaffolds. For their in vivo uses, a sterilization method without severe impairment of original material properties and performance is necessary. Gamma-ray radiation has been commonly applied for sterilization of medical products because of its simple and uniform sterilization without heat generation.[…]”*

In the article “Effective gamma-ray sterilization and characterization of conductive polypyrrole biomaterials” by Semin Kim et. al cited here, the authors describe the first study on gamma-ray sterilization of PPy bioelectrodes and its effects on their characteristics.

The surface topography and roughness of the PPy and γ-PPy electrodes were analyzed by atomic force microscopy. The experiments were performed using a NanoWorld Pointprobe® NCHR AFM probe. All images were acquired at a 0.3 Hz scan rate in tapping mode.

Figure 2 from “Effective gamma-ray sterilization and characterization of conductive polypyrrole biomaterials”: (a) Atomic force micrographs of PPy and γ-PPy samples irradiated with different doses of gamma-ray. (b) Average roughness (root mean square) of PPy and γ-PPy samples. NanoWorld Pointprobe NCHR AFM probes were used for the imaging.
Figure 2 from “Effective gamma-ray sterilization and characterization of conductive polypyrrole biomaterials”: (a) Atomic force micrographs of PPy and γ-PPy samples irradiated with different doses of gamma-ray. (b) Average roughness (root mean square) of PPy and γ-PPy samples.

*Semin Kim, Jin-Oh Jeong, Sanghun Lee, Jong-Seok Park, Hui-Jeong Gwon, Sung In Jeong, John George Hardy, Youn-Mook Lim, Jae Young Lee
Effective gamma-ray sterilization and characterization of conductive polypyrrole biomaterials
Nature Scientific Reports, volume 8, Article number: 3721 (2018)
DOI: https://doi.org/10.1038/s41598-018-22066-6

Please follow this external link for the full article: https://rdcu.be/bariF

Open Access: The article “Effective gamma-ray sterilization and characterization of conductive polypyrrole biomaterials” by Semin Kim et. al 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/.