Micro and Nano Systems Laboratory (MNSL) for Biomedical Engineering

The ultimate goal of our laboratory is to advance the fields of BioMEMS/NEMS, bioelectronic medicine, and translational therapeutics to enhance human health and quality of life. To achieve this, we employ a highly multidisciplinary approach that integrates micro/nano-engineering, semiconductor microfabrication, electronic engineering, and biomedical sciences. Our research scope spans from in vitro platforms to in vivo systems, with a strong focus on designing and developing innovative micro- and nanoscale devices and systems.

Specifically, our lab is leading research on advanced auditory interfaces for next-generation cochlear implants, focusing on low-power artificial basilar membranes and drug-releasing microelectrodes. Furthermore, we are developing in vitro platforms for bionic twin-based drug evaluation, as well as flexible devices for wearable cardiovascular monitoring. Concurrently, our research investigates energy harvesting and wireless power transfer technologies to power implantable therapeutic devices.

1. Therapeutic Auditory Interface

• Artificial Basilar Membrane (ABM): We developed ultra-compact ABM devices capable of replacing conventional microphone, ADC, and DSP modules using piezoelectric (AlN) and triboelectric mechanisms. Integrated with signal processing and microelectrodes, our ABM prototype successfully restored hearing in deaf animal models via Auditory Brainstem Response (ABR) measurements (Sci. Rep. 2015; Adv. Healthc. Mater. 2016 Cover; JMM 2017; IEEE MEMS 2017, Microsyst. Nanoeng. 2022).

• Drug-Releasing Microelectrodes: To preserve residual hearing and minimize tissue fibrosis caused by electrode insertion, we proved that localized steroid delivery significantly preserves hearing (Acta Oto-Laryngol. 2015, 2020; Sci. Rep. 2024; CEO 2025). Furthermore, we integrated drug-delivery functions into electrode architectures using Two-Photon Polymerization (2PP) 3D printing (Adv. Healthc. Mater. 2019, Nanoscribe Showcase) and multi-drug releasing biodegradable implants (Sens. Actuators B 2025, ETnews Highlight).

Ongoing Projects & Collaborations: 

Supported by the Korea Medical Device Development Fund (KMDF, 2021–2023), our current efforts focus on ultra-low-power cochlear implant systems funded by the NRF Glocal R&D Program (PI, 2025–2028 with Kumoh National Institute of Technology). In addition, through the Australia-Korea Foundation (AKF, 2026–2027), we are conducting joint international research with ESIA and Monash University to validate next-generation auditory implants in animal models.

2. Bioinstrumentation and Wearable Devices

• PDC Electrodes for Cardiac Pacemakers: To address impedance buildup and power consumption caused by long-term pacemaker lead implantation (e.g., Medtronic pacemakers), we developed polymer-derived ceramic (PDC) electrodes alongside an in vitro evaluation platform (ACS Appl. Mater. Interfaces 2020). In collaboration with Empa (Swiss Federal Laboratories for Materials Science and Technology), we analyzed their biocompatibility and electrochemical performance (Ceram. Int. 2021).

• 3D Muscle Bionic Twin Platform: Supported by the NRF STEAM Pioneer Project (2024–2028), we are developing a bio-measurement platform that integrates piezoelectric cantilevers with microelectrodes. This platform enables simultaneous electrical stimulation and real-time biomechanical measurement of 3D muscle tissue contraction. Together with KIMS, Chonnam National University, Korea University, and Kangwon National University, we are building a patient-derived bionic twin system for Amyotrophic Lateral Sclerosis (ALS) drug discovery.

• Wearable Cardiovascular Monitoring: Under the Regional Leading Research Center (RLRC) program (2024–2030), we are integrating high-performance flexible piezoelectric sensors into smartwatch-form wearable devices. By combining these sensors with machine learning algorithms for pulse wave analysis, we enhance the accuracy of non-invasive pulse and blood pressure tracking. In collaboration with Yeungnam University Medical Center, we are collecting clinical data for continuous blood pressure and metabolic health monitoring (Endocrinology) and preparing clinical trials for maternal-fetal monitoring (Obstetrics and Gynecology).

3. Wireless Power Transfer & Energy Harvesting for Bio-Implants

• Magneto-Mechano-Electric (MME) Power Generation: Building on prior national project leadership at the Korea Institute of Materials Science (KIMS, 2019–2024), we developed single-crystal piezoelectric composite-based MME generators that achieved world-record output powers exceeding 50 mW (Adv. Funct. Mater. 2022; Adv. Sci. 2024), demonstrating battery-free wireless sensing systems.

• Reliability & Accelerated Life Testing (ALT): To guarantee long-term implant stability, we established life-prediction models and design guidelines for piezoelectric composites under multi-environmental stress conditions (Nano Energy 2021, 2022, 2023). These MME principles and ALT methodologies are currently applied to secure the operational reliability of wireless power receivers in medical implants.

• Acoustic Power & Data Transfer for MRI-Compatible Implants: To eliminate bulky internal coils and permanent magnets—which typically restrict patients from undergoing MRI scans—we are pioneering acoustic energy-based transfer systems. This technology enables simultaneous power and data transmission, paving the way for ultra-low-power, fully MRI-compatible next-generation cochlear implants.