Organic mixed ionic-electronic conductors have emerged as a key material for the development of bioelectronic devices due to their soft mechanical properties, biocompatibility, and high volumetric capacitance. In particular, PEDOT:PSS has become a choice material because it is highly conductive, easily processible, and commercially available. However, PEDOT:PSS is dispersible in water, leading to delamination of films when exposed to biological environments.
View Article and Find Full Text PDFScalable electronic brain implants with long-term stability and low biological perturbation are crucial technologies for high-quality brain-machine interfaces that can seamlessly access delicate and hard-to-reach regions of the brain. Here, we created "NeuroRoots," a biomimetic multi-channel implant with similar dimensions (7 m wide and 1.5 m thick), mechanical compliance, and spatial distribution as axons in the brain.
View Article and Find Full Text PDFSafe and long-term electrical stimulation of neurons requires charge injection without damaging the electrode and tissue. A common strategy to diminish adverse effects includes the modification of electrodes with materials that increases the charge injection capacity. Due to its high capacitance, the conducting polymer PEDOT:PSS is a promising coating material; however, the neural stimulation performance in terms of stability and safety remains largely unexplored.
View Article and Find Full Text PDFTransparent microelectrode arrays enable simultaneous electrical recording and optical imaging of neuronal networks in the brain. Electrodes made of the conducting polymer poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT:PSS) are transparent; however, device fabrication necessitates specific processes to avoid deterioration of the organic material. Here, we present an innovative fabrication scheme for a neural probe that consists of transparent PEDOT:PSS electrodes and demonstrate its compatibility with 2-photon microscopy.
View Article and Find Full Text PDFGlioblastoma is difficult to eradicate with standard oncology therapies due to its high degree of invasiveness. Bioelectric treatments based on pulsed electric fields (PEFs) are promising for the improvement of treatment efficiency. However, they rely on rigid electrodes that cause acute and chronic damage, especially in soft tissues such as the brain.
View Article and Find Full Text PDFGlioblastoma Multiforme is a highly lethal form of brain cancer, resistant to traditional therapeutic approaches and oftentimes hardly resectable. The application of pulsed electric fields (PEF) is gaining prominence as a highly effective approach for combating malignant tumors. However, PEF application at high voltages can generate reactive oxygen species through electrochemical events at electrodes, which can greatly affect intracellular processes and damage healthy cells.
View Article and Find Full Text PDFObjective: Monitoring of impedance changes during electroporation-based treatments can be used to study the biological response and provide feedback regarding treatment progression. However, seamless integration of the sensing electrodes with the setup can be challenging and high impedance sensing electrodes limit the recording sensitivity as well as the spatial resolution. Here, we present an all-in-one microchip containing stimulation electrodes, as well as an array of low impedance, micro-scale sensing electrodes for highly sensitive impedance monitoring.
View Article and Find Full Text PDFThe combination of Ca ions and electroporation has gained attention as potential alternative to electrochemotherapy. Ca is an important component of the cell membrane repair system and its presence directly influences the dynamics of the pore cycle after electroporation which can be exploited for cancer therapies. Here, the influence of Ca concentration is investigated on small molecule electrotransfer and release of Calcein from 4T1, MX-1, B16F10, U87 cancer cells after cell exposure to microsecond electric pulses.
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