Understanding the mechanisms underlying cell-surface interaction is of fundamental importance for the rational design of scaffolds aiming at tissue engineering,tissue repair and neural regeneration applications.Here,w...Understanding the mechanisms underlying cell-surface interaction is of fundamental importance for the rational design of scaffolds aiming at tissue engineering,tissue repair and neural regeneration applications.Here,we examined patterns of neuroblastoma cells cultured in three-dimensional polymeric scaffolds obtained by two-photon lithography.Because of the intrinsic resolution of the technique,the micrometric cylinders composing the scaffold have a lateral step size of^200 nm,a surface roughness of around 20 nm,and large values of fractal dimension approaching 2.7.We found that cells in the scaffold assemble into separate groups with many elements per group.After cell wiring,we found that resulting networks exhibit high clustering,small path lengths,and small-world characteristics.These values of the topological characteristics of the network can potentially enhance the quality,quantity and density of information transported in the network compared to equivalent random graphs of the same size.This is one of the first direct observations of cells developing into 3D small-world networks in an artificial matrix.展开更多
Microelectrode arrays(MEAs)have enabled investigation of cellular networks at sub-millisecond temporal resolution.However,current MEAs are limited by the large electrode footprint since reducing the electrode’s geome...Microelectrode arrays(MEAs)have enabled investigation of cellular networks at sub-millisecond temporal resolution.However,current MEAs are limited by the large electrode footprint since reducing the electrode’s geometric area to sub-cellular dimensions leads to a significant increase in impedance thus affecting its recording capabilities.We report a breakthrough ultra-microelectrodes platform by leveraging the outstanding surface-to-volume ratio of nanowire-templated out-of-plane synthesized three-dimensional fuzzy graphene(NT-3DFG).The enormous surface area of NT-3DFG leads to 140-fold reduction in electrode impedance compared to bare Au microelectrodes,thus enabling scaling down the geometric size by 625-fold to ca.2µm×2µm.The out-of-plane morphology of NT-3DFG leads to a tight seal with the cell membrane thus enabling recording of electrical signals with high signal-to-noise ratio(SNR)of>6.This work highlights the possibility to push the limits of the conventional MEA technology to enable electrophysiological investigation at sub-cellular level without the need of any surface coatings.This presented approach would greatly impact our basic understanding of signal transduction within a single cell as well as complex cellular assemblies.展开更多
文摘Understanding the mechanisms underlying cell-surface interaction is of fundamental importance for the rational design of scaffolds aiming at tissue engineering,tissue repair and neural regeneration applications.Here,we examined patterns of neuroblastoma cells cultured in three-dimensional polymeric scaffolds obtained by two-photon lithography.Because of the intrinsic resolution of the technique,the micrometric cylinders composing the scaffold have a lateral step size of^200 nm,a surface roughness of around 20 nm,and large values of fractal dimension approaching 2.7.We found that cells in the scaffold assemble into separate groups with many elements per group.After cell wiring,we found that resulting networks exhibit high clustering,small path lengths,and small-world characteristics.These values of the topological characteristics of the network can potentially enhance the quality,quantity and density of information transported in the network compared to equivalent random graphs of the same size.This is one of the first direct observations of cells developing into 3D small-world networks in an artificial matrix.
基金T.C.-K.acknowledges funding support from the National Science Foundation under Award No.CBET1552833 and the Office of Naval Research under Award No.N000141712368.J.B.and A.W F.acknowledge financial support from the Dowd Fellowship from the College of Engineering at Carnegie Mellon University.L.M.and F.S.acknowledge Valentina Mollo for ssthe preparation of SEM/FIB samples.We also acknowledge support from the Department of Materials Science and Engineering Materials Characterization Facility(MCF-677785).
文摘Microelectrode arrays(MEAs)have enabled investigation of cellular networks at sub-millisecond temporal resolution.However,current MEAs are limited by the large electrode footprint since reducing the electrode’s geometric area to sub-cellular dimensions leads to a significant increase in impedance thus affecting its recording capabilities.We report a breakthrough ultra-microelectrodes platform by leveraging the outstanding surface-to-volume ratio of nanowire-templated out-of-plane synthesized three-dimensional fuzzy graphene(NT-3DFG).The enormous surface area of NT-3DFG leads to 140-fold reduction in electrode impedance compared to bare Au microelectrodes,thus enabling scaling down the geometric size by 625-fold to ca.2µm×2µm.The out-of-plane morphology of NT-3DFG leads to a tight seal with the cell membrane thus enabling recording of electrical signals with high signal-to-noise ratio(SNR)of>6.This work highlights the possibility to push the limits of the conventional MEA technology to enable electrophysiological investigation at sub-cellular level without the need of any surface coatings.This presented approach would greatly impact our basic understanding of signal transduction within a single cell as well as complex cellular assemblies.
