Electronic transducers of neuronal cellular activity are important devices in neuroscience and neurology. Organic field-effect transistors (OFETs) offer tailored surface chemistry, mechanical flexibility, and high sensitivity to electrostatic potential changes at device interfaces. These properties make them attractive for interfacing electronics with neural cells and performing extracellular recordings and stimulation of neuronal network activity. In this work we operate pentacene ultra-thin film (9 nm thick) transistors with a liquid gate both as transducers and electrical stimulators of neuronal network activity. These devices are highly sensitive to small potential changes in cell medium and exhibit sufficient stability under standard cell culture conditions for nine days. We show that murine neural stem cells can be adhered on top of functional devices without the need for an additional layer of cell-adhesive molecules, and then differentiated into neuronal networks. OFET response is monitored during the different phases of the neuronal differentiation process up to nine days. Only when stem cells are differentiated into neurons, it is possible to measure electrical signals in the OFET current following the stimulation. Due to the large sensing area of our device, which accommodates from hundreds to thousands of interconnected neurons, the OFET electrical signals arise from the collective electrophysiological response of the neuronal population. The maximum extracellular potential change in the cleft region adjacent to the transistor surface amounts to 350 μV. This demonstrates that pentacene ultra-thin film OFETs enable good cellular adhesion and efficient coupling of the ionic currents at the biological–organic semiconductor interface with the OFET current.

We demonstrate an electrolyte-gated hybrid nanoparticle/organic synapstor (synapse-transistor, termed EGOS) that exhibits short-term plasticity as biological synapses. The response of EGOS makes it suitable to be interfaced with neurons: short-term plasticity is observed at spike voltage as low as 50 mV (in a par with the amplitude of action potential in neurons) and with a typical response time in the range of tens milliseconds. Human neuroblastoma stem cells are adhered and differentiated into neurons on top of EGOS. We observe that the presence of the cells does not alter short-term plasticity of the device.Comment: Full paper, figures and supporting informatio

Silver nanoparticles (AgNPs) hold great promise in biomedical applications due to their unique properties and potential for specific tissue targeting. However, the clinical translation of nanoparticle-based therapeutics remains challenging, primarily due to an incomplete understanding of how nanoparticle properties influence interactions at the nano-bio interface, as well as the role of surface-adsorbed proteins (i.e., protein corona) in modulating nanoparticle-cell interactions. This study demonstrates that the surface charge has a greater influence than protein corona formation in determining the cytotoxicity, cellular uptake, and biodistribution of AgNPs. Using negatively and positively charged AgNPs, we show that while protein corona formation is essential for ensuring nanoparticle availability for cellular interactions, the adsorption of biomolecules is nonspecific and independent of surface charge. Conversely, the surface charge significantly influences the interactions of AgNPs with cells. Positively charged nanoparticles exhibit enhanced cellular uptake, preferential accumulation in lysosomes, and pronounced mitochondrial damage compared to their negatively charged counterparts, resulting in greater cytotoxic effects. This effect is particularly evident in human breast cancer cells, where negatively charged nanoparticles show minimal uptake and cytotoxicity. These findings demonstrate that surface charge is the primary factor governing nanoparticle-cell interactions rather than protein corona formation. Nonetheless, the protein corona plays a critical role in stabilizing nanoparticles in physiological environments.

The role of the surface properties of nanoparticles in serum protein adsorption, cellular uptake and cytotoxicity is reported. The surface properties of nanoparticles regulate their ability to adsorb proteins and determine their biological outcomes.

Keratin/hydrotalcites hybrid nanofibers loaded with diclofenac were proposed as a potential drug delivery system and scaffold for cells growth.