Growth Mechanism of Cluster-Assembled Surfaces: From Submonolayer to Thin-Film Regime

Borghi, Francesca; Podestà, Alessandro; Piazzoni, Claudio; Milani, Paolo

doi:10.1103/physrevapplied.9.044016

Cited by 52 publications

(91 citation statements)

References 77 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The observation of such size effect in WF measurements, is an addtitional confirmation that that NS films synthetized with the SCBD grow without coalescence retaining the memory of the small size of their gas-phase precursors. [47][48][49][50][51] As a consequence of this "memory effect" SCBD allows to exploit quantum confinement to synthetize samples with a remarkably high WF and a low stoichiometry without any sputtering process or additional heating treatment.…”

Section: The Work Functionmentioning

confidence: 99%

Interplay among work function, electronic structure and stoichiometry in nanostructured VO_x films

D׳Elia

Cepek

Simone

et al. 2020

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

The work function is the parameter of greatest interest in many technological applications involving charge exchange mechanisms at the interface. The possibility to produce samples with a controlled work function is then particularly interesting, albeit challenging. We synthetized nanostructured vanadium oxides films by a room temperature Supersonic Cluster Beam Deposition method, obtaining samples with tunable stoichiometry and work function (3.7-7 eV). We present an investigation of the electronic structure of several vanadium oxides films as a function of the oxygen content via in-situ Auger, valence-band photoemission spectroscopy and work function measurements.The experiments probed the partial 3d density of states, highlighting the presence of strong V3d-O2p and V3d-V4s hybridization which influence 3d occupation. We show how controlling the stoichiometry of the sample implies a control over work function, and that the access to nanoscale quantum confinement can be exploited to increase the work function of the sample relative to the bulk analogue. In general, the knowledge of the interplay among work function, electronic structure, and stoichiometry is strategic to match nanostructured oxides to their target applications.

show abstract

Section: The Work Functionmentioning

confidence: 99%

Interplay among work function, electronic structure and stoichiometry in nanostructured VO_x films

D׳Elia

Cepek

Simone

et al. 2020

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…The surface profiles of nanostructured zirconia films are characterised by peaks and valleys (see Figure 4c), defining a complex random pattern of nanoscale features, whose dimensions and spatial distribution resemble those found in natural ECM topographies 5,6 . The specific surface area, the rms roughness, the average lateral dimensions of the largest morphological features (the correlation length ξ), as well as the interfacial porosity of the films typically increase with film thickness 59,60,89 . The interfacial open pores, delimited and defined by the surface asperities 44 , can accommodate proteins (including fibronectin) and nutrients 31,[89][90][91][92] ; asperities evolve in height, area, and surface charge density 81 .…”

Section: Cell Culture and Preparation For The Force Spectroscopy Expementioning

confidence: 99%

“…60, 120, 240 s, accordingly. During the contact time, the Z-piezo position was kept constant using the Z closed-loop feedback mode.…”

mentioning

confidence: 94%

Adhesion force spectroscopy with nanostructured colloidal probes reveals nanotopography-dependent early mechanotransductive interactions at the cell membrane level

Chighizola

Previdi

Dini

et al. 2020

Preprint

View full text Add to dashboard Cite

Mechanosensing, the ability of cells to perceive and interpret the microenvironmental biophysical cues (such as the nanotopography), impacts strongly on cellular behaviour through mechanotransductive processes and signalling. These events are predominantly mediated by integrins, the principal cellular adhesion receptors located at the cell/extracellular matrix (ECM) interface.Because of the typical piconewton force range and nanometre length scale of mechanotransductive interactions, achieving a detailed understanding of the spatiotemporal dynamics occurring at the cell/microenvironment interface is challenging; sophisticated interdisciplinary methodologies are required. Moreover, an accurate control over the nanotopographical features of the microenvironment is essential, in order to systematically investigate and precisely assess the influence of the different nanotopographical motifs on the mechanotransductive process.In this framework, we were able to study and quantify the impact of microenvironmental nanotopography on early cellular adhesion events by means of adhesion force spectroscopy based on innovative colloidal probes mimicking the nanotopography of natural ECMs.These probes provided the opportunity to detect nanotopography-specific modulations of the molecular force loading dynamics and integrin clustering at the level of single binding events, in the critical time window of nascent adhesion formation. Following this approach, we found that the nanotopographical features are responsible for an excessive force loading in single adhesion sites after 20 -60 s of interaction, causing a drop in the number of adhesion sites. However, by manganese treatment we demonstrated that the availability of activated integrins is a critical regulatory factor for these nanotopography-dependent dynamics. KEYWORDSMechanosensing, mechanotransduction, mechanobiology, cell adhesion, nanotopography, nanostructured materials, cell microenvironment, extracellular matrix, atomic force microscopy, colloidal probes, adhesion force spectroscopy, integrin binding, adhesion complexes.Production of Poly-L-lysine -coated CPs. Also for reference purposes, CPs were coated with poly-L-lysine (PLL). PLL is a poly-amino acid routinely used to facilitate protein absorption and the attachment of cells to solid surfaces in biological applications, including our previous experiments with PC12 cells 44,64 . For the PLL coating, the probes were incubated with a 0.1% (w/v) PLL solution (Sigma-Aldrich) at room temperature for 30 min, and washed thoroughly afterwards with milliQ water several times before the measurements.

show abstract

“…with disordered yet controlled topographical features based on the assembling of zirconia nanoparticles, produced in the gas phase and accelerated in a supersonic expansion, on flat substrates (23). This bottom-up assembling technique produces nanostructured films with a nanoscale topography accurately controlled in a reproducible manner (23), (24), (26), (27).…”

Section: Micropattern Fabricationmentioning

confidence: 99%

Neuronal Cells Confinement by Micropatterned Cluster-Assembled Dots with Mechanotransductive Nanotopography

Schulte

Lamanna

Moro

et al. 2018

Preprint

Self Cite

View full text Add to dashboard Cite

The in vitro fabrication of neural networks able to simulate brain circuits and to maintain their native connectivity is of strategic importance to gain a deep understanding of neural circuit physiology and brain natural computational algorithm(s). This would also enable a wide-range of applications including the development of efficient brain-on-chip devices or brain-computer interfaces. Chemical and mechanotransductive cues cooperate to promote proper development and functioning of neural networks. Since the 80's, controlled growth of mammalian neuronal cells on micrometric patterned chemical cues with the development of synaptic connections and electrical activity has been reported, however the role of mechanotransductive signaling on the growth/organization of neural networks has not been investigated so far. Here we report the fabrication and characterization of patterned substrates for neuronal culture with a controlled structure both at the nano-and microscale suitable for the selective adhesion of neuronal cells. Nanostructured micrometric dots were patterned on passivated cell-repellent glass substrates by supersonic cluster beam deposition of zirconia nanoparticles through stencil masks. Cluster-assembled nanostructured zirconia surfaces are characterized by nanotopographical features that can direct the maturation of neural networks by mechanotransductive signaling. Our approach produces a controlled microscale pattern of adhesive areas with predetermined nanoscale morphology. We have validated these micropatterned substrates using a neuronal cell line (PC12 cells) and cultured hippocampal neurons. While cells have been uniformly plated on the substrates, they adhered only on the nanostructured zirconia regions, remaining effectively confined inside the nanostructured dots on which they were found to grow, move and differentiate.

show abstract

Growth Mechanism of Cluster-Assembled Surfaces: From Submonolayer to Thin-Film Regime

Cited by 52 publications

References 77 publications

Interplay among work function, electronic structure and stoichiometry in nanostructured VO_x films

Interplay among work function, electronic structure and stoichiometry in nanostructured VO_x films

Adhesion force spectroscopy with nanostructured colloidal probes reveals nanotopography-dependent early mechanotransductive interactions at the cell membrane level

Neuronal Cells Confinement by Micropatterned Cluster-Assembled Dots with Mechanotransductive Nanotopography

Contact Info

Product

Resources

About

Growth Mechanism of Cluster-Assembled Surfaces: From Submonolayer to Thin-Film Regime

Cited by 52 publications

References 77 publications

Interplay among work function, electronic structure and stoichiometry in nanostructured VOx films

Interplay among work function, electronic structure and stoichiometry in nanostructured VOx films

Adhesion force spectroscopy with nanostructured colloidal probes reveals nanotopography-dependent early mechanotransductive interactions at the cell membrane level

Neuronal Cells Confinement by Micropatterned Cluster-Assembled Dots with Mechanotransductive Nanotopography

Contact Info

Product

Resources

About

Interplay among work function, electronic structure and stoichiometry in nanostructured VO_x films

Interplay among work function, electronic structure and stoichiometry in nanostructured VO_x films