Control of spatial cell attachment on carbon nanofiber patterns on polycarbonate urethane-7

<p><b>Copyright information:</b></p><p>Taken from "Control of spatial cell attachment on carbon nanofiber patterns on polycarbonate urethane"</p><p></p><p>International Journal of Nanomedicine 2006;1(3):361-365.</p><p>Published online Jan 2006</p><p>PMCID:PMC2426804.</p><p>© 2006 Dove Medical Press Limited. All rights reserved</p

Control of spatial cell attachment on carbon nanofiber patterns on polycarbonate urethane-0

<p><b>Copyright information:</b></p><p>Taken from "Control of spatial cell attachment on carbon nanofiber patterns on polycarbonate urethane"</p><p></p><p>International Journal of Nanomedicine 2006;1(3):361-365.</p><p>Published online Jan 2006</p><p>PMCID:PMC2426804.</p><p>© 2006 Dove Medical Press Limited. All rights reserved</p

Control of spatial cell attachment on carbon nanofiber patterns on polycarbonate urethane-1

<p><b>Copyright information:</b></p><p>Taken from "Control of spatial cell attachment on carbon nanofiber patterns on polycarbonate urethane"</p><p></p><p>International Journal of Nanomedicine 2006;1(3):361-365.</p><p>Published online Jan 2006</p><p>PMCID:PMC2426804.</p><p>© 2006 Dove Medical Press Limited. All rights reserved</p

Non-selective endothelial cell (RAEC) adhesion to PCU compared with CNF regions

Bar = 10 μm.<p><b>Copyright information:</b></p><p>Taken from "Control of spatial cell attachment on carbon nanofiber patterns on polycarbonate urethane"</p><p></p><p>International Journal of Nanomedicine 2006;1(3):361-365.</p><p>Published online Jan 2006</p><p>PMCID:PMC2426804.</p><p>© 2006 Dove Medical Press Limited. All rights reserved</p

Analysis of Osteoblast Differentiation on Polymer Thin Films Embedded with Carbon Nanotubes

<div><p>Osteoblast differentiation can be modulated by variations in order of nanoscale topography. Biopolymers embedded with carbon nanotubes can cause various orders of roughness at the nanoscale and can be used to investigate the dynamics of extracellular matrix interaction with cells. In this study, clear relationship between the response of osteoblasts to integrin receptor activation, their phenotype, and transcription of certain genes on polymer composites embedded with carbon nanotubes was demonstrated. We generated an ultrathin nanocomposite film embedded with carbon nanotubes and observed improved adhesion of pre-osteoblasts, with a subsequent increase in their proliferation. The expression of genes encoding integrin subunits α₅, α_v, β₁, and β₃ was significantly upregulated at the early of time-point when cells initially attached to the carbon nanotube/polymer composite. The advantage of ultrathin nanocomposite film for pre-osteoblasts was demonstrated by staining for the cytoskeletal protein vinculin and cell nuclei. The expression of essential transcription factors for osteoblastogenesis, such as Runx2 and Sp7 transcription factor 7 (known as osterix), was upregulated after 7 days. Consequently, the expression of genes that determine osteoblast phenotype, such as alkaline phosphatase, type I collagen, and osteocalcin, was accelerated on carbon nanotube embedded polymer matrix after 14 days. In conclusion, the ultrathin nanocomposite film generated various orders of nanoscale topography that triggered processes related to osteoblast bone formation.</p></div

Pre-osteoblast proliferation, integrin activation, cytoskeletal organization, and focal adhesion on PCU and CNT/PCU composites.

<p>(a) Actin cytoskeleton (green) and focal adhesions (red) of pre-osteoblasts grown on the PCU (a, d), 10% CNT/PCU (b, e), and 50% CNT/PCU (c, f) surfaces after 24 hrs. (g) Fold change of mRNA expression levels of α_1, α₂, α_5, and α_v integrin and of (h) β₁ and β₃ integrin in pre-osteoblasts grown on the PCU (orange), 10% CNT/PCU (gray), and 50% CNT/PCU (dark gray) surfaces were assessed by qPCR after 24 hrs in culture. (i) Fold change of pre-osteoblast cell proliferation on CNT/PCU composites compared with that on the pure PCU surface after 24 hrs. All data represent the mean ± SEM (<i>n</i> = 3). *<i>p</i> < 0.05, **<i>p</i> < 0.01, ***<i>p</i> < 0.001 <i>vs</i>. control (PCU) and ^###<i>p</i> < 0.001 <i>vs</i>. CNT/PCU composites.</p

Transcriptional and phenotype gene expression of osteoblasts on PCU and CNT/PCU composites.

<p>The mRNA levels of (a) <i>Sp7</i> and <i>Runx2</i> at 7 days and (b) <i>Ibsp</i>, <i>Alpl</i>, <i>Col1</i>, <i>Spp1</i>, and <i>Bglap</i> after 14 days in osteoblasts grown on the PCU (orange) and CNT/PCU composite surfaces (gray for 10% CNT and dark gray for 50% of CNT in PCU) were determined by qPCR. (c) Dominant biomarkers of osteoblast responses (short and long term). All data represent the mean ± SEM (<i>n</i> = 3). *<i>p</i> < 0.05, **<i>p</i> < 0.01, ***<i>p</i> < 0.001 <i>vs</i>. control (PCU).</p

Fabrication, surface transparency, and surface morphology of CNT/PCU composite thin film.

<p>(a) A schematic showing the fabrication of a CNT/PCU composite thin film using spin casting techniques. (b) Transparency of PCU, 10% CNT/PCU, and 50% CNT/PCU. The CNT/PCU composites were made transparent under visible and optical microscopy. (c). Nanoscale surface topography of PCU, 10% CNT/PCU, and 50% CNT/PCU, as determined by AFM. An increase in the presence of nanostructures corresponded with increasing levels of CNTs embedded in PCU.</p

Thickness, roughness, and contact angle of CNT/PCU composites.

<p>(a) The film thickness was 60 nm for CNT/PCU. The thickness of the pure PCU surface was around 100 nm (data not shown). (b) Roughness (RMS) analysis of PCU (orange) and CNT/PCU composites (gray for 10% CNT and dark gray for 50% of CNT in PCU) showed increased nanoscale roughness as the quantity of CNTs embedded in PCU increased. (d) Goniometry revealed increase in contact angle with increase of CNT amount in PCU matrix. All data represent the mean ± SEM (<i>n</i> = 3). *<i>p</i> < 0.05, **<i>p</i> < 0.01, and ***<i>p</i> < 0.001 <i>vs</i>. control (PCU).</p

Interaction forces between carbon nanofiber (CNF) and polycarbonate urethane (PCU) without (a and b) and with (c and d) fibronectin-coated tips

<p><b>Copyright information:</b></p><p>Taken from "Selective adhesion and mineral deposition by osteoblasts on carbon nanofiber patterns"</p><p></p><p>International Journal of Nanomedicine 2006;1(1):65-72.</p><p>Published online Jan 2006</p><p>PMCID:PMC2426764.</p><p>© 2006 Dove Medical Press Limited. All rights reserved</p