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Brauweiler-Reuters, E.

Publications and source records attributed to Brauweiler-Reuters, E..

2 recordsLinked to original sources

Hierarchical dendrite-inspired organic bioelectronic interfaces for neuronal integration

Brain-machine interfaces rely on intimate electrical communication between living neurons and artificial materials, yet conventional electrode architectures remain structurally different to neuronal tissue, limiting stable cell-electrode coupling and long-term recording. Although conducting polymers and microstructured interfaces have individually improved the electrochemical and biological properties of neural electrodes, integrating neuromimetic architecture with electrically active organic materials to direct neuron-electrode interactions has remained challenging. Here we engineer dendrite-inspired organic microelectrodes by programming the self-assembly of conducting polymer fibers directly on microelectrode arrays. By controlling the electrodeposition process, we generate hierarchical architectures that emulate key stages of dendritic development while preserving the relevant electrochemical properties of conducting polymers. These bioinspired interfaces promote nanoscale membrane conformability, reduce the neuron-electrode cleft, and induce localized membrane engulfment of the electrode structures. The enhanced structural integration is accompanied by increased synaptic protein expression and neuronal excitability within mature primary cortical networks. Furthermore, the dendritic electrodes enable localized laser-assisted optoporation, providing transient intracellular electrophysiological access while maintaining extracellular recording functionality.

neuroscience↗

Correlating surface plasmon resonance microscopy of living and fixated cells with electron microscopy allows for investigation of potential preparation artifacts

AO_SCPLOWBSTRACTC_SCPLOWThe investigation of the cell-substrate interface is of great importance for a broad spectrum of areas such as biomedical engineering, brain-chip interfacing and fundamental research. Due to its unique resolution and the prevalence of instruments, electron microscopy (EM) is used as one of the standard techniques for the analysis of the cell-substrate interface. However, possible artifacts that might be introduced by the required sample preparation have been the subject of speculation for decades. Due to recent advances in Surface plasmon resonance microscopy (SPRM), the technique now offers a label-free alternative for the interface characterization with nanometer resolution in axial direction. In contrast to EM, SPRM studies do not require fixation and can therefore be performed on living cells. Here, we present a workflow that allows us to quantify the impact of chemical fixation on the cell-substrate interface. These measurements confirmed that chemical fixation preserved the average cell-substrate distances in the majority of studied cells. Furthermore, we were able to correlate the SPRM measurements with EM images of the cell-substrate interface of the exact same cells allowing us to identify regions with good agreement between the two methods and reveal artifacts introduced during further sample preparation.

biophysics↗