by Keyword: Nanopattern

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Casanellas, Ignasi, Lagunas, Anna, Vida, Yolanda, Pérez-Inestrosa, Ezequiel, Andrades, J. A., Becerra, J., Samitier, Josep, (2020). The Janus role of adhesion in chondrogenesis International Journal of Molecular Sciences 21, (15), 5269

Tackling the first stages of the chondrogenic commitment is essential to drive chondrogenic differentiation to healthy hyaline cartilage and minimize hypertrophy. During chondrogenesis, the extracellular matrix continuously evolves, adapting to the tissue adhesive requirements at each stage. Here, we take advantage of previously developed nanopatterns, in which local surface adhesiveness can be precisely tuned, to investigate its effects on prechondrogenic condensation. Fluorescence live cell imaging, immunostaining, confocal microscopy and PCR analysis are used to follow the condensation process on the nanopatterns. Cell tracking parameters, condensate morphology, cell–cell interactions, mechanotransduction and chondrogenic commitment are evaluated in response to local surface adhesiveness. Results show that only condensates on the nanopatterns of high local surface adhesiveness are stable in culture and able to enter the chondrogenic pathway, thus highlighting the importance of controlling cell–substrate adhesion in the tissue engineering strategies for cartilage repair.

Keywords: Dendrimer, Nanopatterning, RGD, Mesenchymal cell condensation, Cell–cell interactions, YAP, Chondrogenesis

Casanellas, Ignasi, Lagunas, Anna, Vida, Yolanda, Pérez-Inestrosa, Ezequiel, Andrades, José A., Becerra, José, Samitier, Josep, (2019). Matrix nanopatterning regulates mesenchymal differentiation through focal adhesion size and distribution according to cell fate Biomimetics Biomimetic Nanotechnology for Biomedical Applications (NanoBio&Med 2018) , MDPI (Barcelona, Spain) 4, (2), 43

Extracellular matrix remodeling plays a pivotal role during mesenchyme patterning into different lineages. Tension exerted from cell membrane receptors bound to extracellular matrix ligands is transmitted by the cytoskeleton to the cell nucleus inducing gene expression. Here, we used dendrimer-based arginine–glycine–aspartic acid (RGD) uneven nanopatterns, which allow the control of local surface adhesiveness at the nanoscale, to unveil the adhesive requirements of mesenchymal tenogenic and osteogenic commitments. Cell response was found to depend on the tension resulting from cell–substrate interactions, which affects nuclear morphology and is regulated by focal adhesion size and distribution.

Keywords: Arginine–glycine–aspartic acid (RGD), Nanopattern, Mesenchymal stem cells, Tenogenesis, Osteogenesis, Cell nuclei, Focal adhesions

Casanellas, Ignasi, Lagunas, Anna, Tsintzou, Iro, Vida, Yolanda, Collado, Daniel, Pérez-Inestrosa, Ezequiel, Rodríguez-Pereira, Cristina, Magalhaes, Joana, Gorostiza, Pau, Andrades, José A., Becerra, José, Samitier, Josep, (2018). Dendrimer-based uneven nanopatterns to locally control surface adhesiveness: A method to direct chondrogenic differentiation Journal of Visualized Experiments Bioengineering, (131), e56347

Cellular adhesion and differentiation is conditioned by the nanoscale disposition of the extracellular matrix (ECM) components, with local concentrations having a major effect. Here we present a method to obtain large-scale uneven nanopatterns of arginine-glycine-aspartic acid (RGD)-functionalized dendrimers that permit the nanoscale control of local RGD surface density. Nanopatterns are formed by surface adsorption of dendrimers from solutions at different initial concentrations and are characterized by water contact angle (CA), X-ray photoelectron spectroscopy (XPS), and scanning probe microscopy techniques such as scanning tunneling microscopy (STM) and atomic force microscopy (AFM). The local surface density of RGD is measured using AFM images by means of probability contour maps of minimum interparticle distances and then correlated with cell adhesion response and differentiation. The nanopatterning method presented here is a simple procedure that can be scaled up in a straightforward manner to large surface areas. It is thus fully compatible with cell culture protocols and can be applied to other ligands that exert concentration-dependent effects on cells.

Keywords: Bioengineering, Dendrimer, Nanopattern, Arginine-Glycine-Aspartic Acid (RGD), Atomic Force Microscopy (AFM), Cell Adhesion, Mesenchymal Stem Cells (Mscs), Chondrogenesis

Gállego, Isaac, Manning, Brendan, Prades, Joan Daniel, Mir, Mònica, Samitier, Josep, Eritja, Ramon, (2017). DNA-origami-driven lithography for patterning on gold surfaces with sub-10 nm resolution Advanced Materials , 29, 1603233

Gállego, Isaac, Manning, Brendan, Prades, Joan Daniel, Mir, Mónica, Samitier, Josep, Eritja, Ramon, (2017). DNA-Origami-Aided Lithography for Sub-10 Nanometer Pattern Printing Proceedings Eurosensors 2017 , MDPI (Paris, France) 1, (4), 325

We report the first DNA-based origami technique that can print addressable patterns on surfaces with sub-10 nm resolution. Specifically, we have used a two-dimensional DNA origami as a template (DNA origami stamp) to transfer DNA with pre-programmed patterns (DNA ink) on gold surfaces. The DNA ink is composed of thiol-modified staple strands incorporated at specific positions of the DNA origami stamp to create patterns upon thiol-gold bond formation on the surface (DNA ink). The DNA pattern formed is composed of unique oligonucleotide sequences, each of which is individually addressable. As a proof-of-concept, we created a linear pattern of oligonucleotide-modified gold nanoparticles complementary to the DNA ink pattern. We have developed an in silico model to identify key elements in the formation of our DNA origami-driven lithography and nanoparticle patterning as well as simulate more complex nanoparticle patterns on surfaces.

Keywords: DNA nanotechnology, Lithography, Nanopatterning, Gold nanoparticles, Metasurfaces

Caballero, D., Samitier, J., Errachid, A., (2009). Submerged nanocontact printing (SnCP) of thiols Journal of Nanoscience and Nanotechnology , 9, (11), 6478-6482

Biological patterned surfaces having sub-micron scale resolution are of great importance in many fields of life science and biomedicine. Different techniques have been proposed for surface patterning at the nanoscale. However, most of them present some limitations regarding the patterned area size or are time-consuming. Micro/nanocontact printing is the most representative soft lithography-based technique for surface patterning at the nanoscale. Unfortunately, conventional micro/nanocontact printing also suffers from problems such as diffusion and stamp collapsing that limit pattern resolution. To overcome these problems, a simple way of patterning thiols under liquid media using submerged nanocontact printing (SnCP) over large areas (similar to cm(2)) achieving nanosize resolution is presented. The technique is also low cost and any special equipment neither laboratory conditions are required. Nanostructured poly(dimethyl siloxane) stamps are replicated from commercially available digital video disks. SnCP is used to stamp patterns of 200 nm 1-octadecanethiol lines in liquid media, avoiding ink diffusion and stamp collapsing, over large areas on gold substrates compared with conventional procedures. Atomic force microscopy measurements reveal that the patterns have been successfully transferred with high fidelity. This is an easy, direct, effective and low cost methodology for molecule patterning immobilization which is of interest in those areas that require nanoscale structures over large areas, such as tissue engineering or biosensor applications.

Keywords: Submerged Nanocontact Printing, Replica Molding, Nanopatterning, Large Area, Dip-pen nanolithography, High-aspect-ratio, Soft lithography, Submicronscale, Nanoimprint lithography, Thin-film, Surfaces, Fabrication, Proteins, Nanofabrication