Lee, Hyunjoo J. c Son, Yoojin Kim, Jeongyeon Lee, C. Justin Yoon, Eui-Sung Cho, Il-Joo 2024-01-20T07:32:49Z 2024-01-20T07:32:49Z 2021-09-05 2015-03 1473-0197 https://pubs.kist.re.kr/handle/201004/125693 Multi-functional neural probes integrated with various stimulation modalities are becoming essential tools in neuroscience to study the brain more effectively. In this paper, we present a new multi-functional neural probe that allows chemical stimulation through drug delivery and simultaneous recording of individual neuron signals through a microelectrode array. By embedding microchannels in silicon using a proposed glass reflow process, we successfully fabricated 40 mu m thick silicon neural probes suitable for small animal experiments. The electrochemical impedance spectroscopy confirms that impedance of iridium microelectrodes is low enough (< 1 M Omega at 1 kHz) to measure neural signals. Flow rate characterization in a 0.9% w/v agarose gel shows the capability to deliver a small volume of drugs (< 1 mu l) at a controlled flow rate. We demonstrate the viability and potential of this new probe by conducting in vivo experiments on mice. Because of the proposed compact structure, both action potentials of individual neurons and local field potentials (LFP) at the thalamus region of a mouse brain were successfully detected with a noise level of similar to 30 mu Vpp. Furthermore, we successfully induced absence seizure by injecting seizure-inducing drugs (baclofen) at a local target region and observed distinctive changes in neural signal patterns. Specifically, spike-wave discharge (SWD), which is an indicative signal pattern of absence seizure, was successfully recorded. These signals were also directly compared to SWD detected after inducing absence seizure through direct injection of baclofen through the abdomen. This work demonstrates the potential of our multi-functional neural probes for use in effective investigation of brain functions and disorders by using widely available mouse models. English Royal Society of Chemistry ABSENCE SEIZURES WIRELESS A multichannel neural probe with embedded microfluidic channels for simultaneous in vivo neural recording and drug delivery Article 10.1039/c4lc01321b 1 Lab on a Chip, v.15, no.6, pp.1590 - 1597 Lab on a Chip 15 6 1590 1597 scie scopus 000350543500022 2-s2.0-84924251146 Biochemical Research Methods Chemistry, Multidisciplinary Chemistry, Analytical Nanoscience & Nanotechnology Instruments & Instrumentation Biochemistry & Molecular Biology Chemistry Science & Technology - Other Topics Instruments & Instrumentation Article ABSENCE SEIZURES WIRELESS neural probe