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Rincon Montes, V.

Publications and source records attributed to Rincon Montes, V..

2 recordsLinked to original sources

A mechanically stable neural probe for percutaneous high-resolution, multichannel recordings in peripheral nerves

The development of neural probes has enabled a deeper understanding and improved treatment for neurological disorders. Microneurography is currently the gold standard for assessing the electrophysiological signature of pain mechanisms in the human peripheral nervous system. However, its clinical utility is limited by the low recording yield and signal-to-noise ratio of single-electrode probes. To overcome these limitations, we developed mechanically robust, multi-electrode probes designed for acute percutaneous insertion and recording in peripheral nerves. The electrical and mechanical stability of these probes was confirmed through repeated insertions in artificial human skin and rat peripheral nerves. In addition, ex vivo and in vivo experiments demonstrated enhanced functional performance, with multi-site recordings enabling the isolation of single-fiber activity. Importantly, our probes can be operated analogously to conventional microneurography needles while substantially increasing the information yield, providing enhanced capabilities for minimally invasive peripheral nerve assessment.

neuroscience↗

PEDOT:PSS conducting eutectogel for enhanced electrical recording and stimulation in implantable neural interfaces

Conductive polymers such as PEDOT:PSS are widely used in bioelectronic interfaces due to their mixed ionic-electronic conductivity and biocompatibility. However, their mechanical fragility and limited processability constrain their performance in implantable devices. Deep eutectic solvents (DES), when combined with PEDOT:PSS, form eutectogels that enable thick, soft coatings. Here, we present a PEDOT:PSS-based eutectogel incorporating choline chloride: lactic acid and GOPS, integrated into flexible thin-film electrode arrays for sciatic nerve interfacing. These implants feature an array of electrodes and a pre-formed spiral geometry to conformally wrap small-diameter nerves. Devices were fabricated using standard photolithography and reactive ion etching techniques, allowing side-by-side comparison of PEDOT:PSS/DES with conventional PEDOT:PSS electrodes. PEDOT:PSS/DES enabled single-layer films up to 800 nm thick, significantly greater than PEDOT:PSS, and yielding over two-fold improvements in impedance and charge injection capacity in vitro. Acute in vivo electrophysiology in rats confirmed enhanced neural recording and stimulation capabilities, with lower impedance, higher capacitance, and reduced motor activation thresholds. While PEDOT:PSS/DES more reliably elicited motor responses at lower stimulation currents, electromyogram signal amplitudes from the tibialis anterioris at matched stimulation levels were comparable between materials. These results suggest that while superior electrochemical properties improve neural interface performance, local electrode-tissue interactions remain critical. Overall, this work establishes DES-modified PEDOT:PSS as a promising electrode material for soft neural interfaces and highlights its potential for advancing implantable bioelectronics.

neuroscience↗