skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Search for: All records

Creators/Authors contains: "Lee, Jimin"

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. Atherosclerosis is a prominent cause of coronary artery disease and broader cardiovascular diseases, the leading cause of death worldwide. Angioplasty and stenting is a common treatment, but in-stent restenosis, where the artery re-narrows, is a frequent complication. Restenosis is detected through invasive procedures and is not currently monitored frequently for patients. Here, we report an implantable vascular bioelectronic device using a newly developed miniaturized strain sensor via microneedle printing methods. A capillary-based printing system achieves high-resolution patterning of a soft, capacitive strain sensor. Ink and printing parameters are evaluated to create a fully printed sensor, while sensor design and sensing mechanism are studied to enhance sensitivity and minimize sensor size. The sensor is integrated with a wireless vascular stent, offering a biocompatible, battery-free, wireless monitoring system compatible with conventional catheterization procedures. The vascular sensing system is demonstrated in an artery model for monitoring restenosis progression. Collectively, the artery implantable bioelectronic system shows the potential for wireless, real-time monitoring of various cardiovascular diseases and stent-integrated sensing/treatments. 
    more » « less
  2. Abstract More than half of all Americans suffer from chronic diseases, the leading causes of death and disability. However, prompt treatment of chronic diseases can lead to better patient outcomes and a reduced burden on the healthcare system. This highlights the urgent need for electrochemical (EC) sensors that provide non‐invasive, real‐time monitoring of disease‐indicating biomarkers. Due to their high sensitivity, high selectivity, and cost‐effectiveness, EC biosensors have recently shown tremendous promise for individualized health monitoring. This review explains the working principles of EC biosensors. It summarizes the recent advances and improvements of EC biosensors for detecting biomarkers in different biofluids, including tears, saliva, breath, urine, and sweat. Through a comprehensive overview of EC biosensor technologies, this article is expected to aid the development of flexible and wearable EC biosensing systems that have the potential to provide continuous, long‐term health monitoring for both clinical and at‐home use. 
    more » « less
  3. The environmental impact of battery electric vehicles (BEVs) largely depends on the environmental profile of the national electric power grid that enables their operation. The purpose of this study is to analyze the environmental performance of BEV usage in Korea considering the changes and trajectory of the national power roadmap. We examined the environmental performance using a weighted environmental index, considering eight impact categories. The results showed that the weighted environmental impact of Korea’s national power grid supply would increase overall by 66% from 2015 to 2029 using the plan laid out by the 7th Power Roadmap, and by only 33% from 2017 to 2031 using the 8th Power Roadmap plan. This change reflects the substantial amount of renewables in the more recent power mix plan. In 2016, BEV usage in Korea resulted in emissions reductions of about 37% compared with diesel passenger vehicles, and 41% compared with gasoline vehicles per kilometer driven (100 g CO2e/km versus 158 g and 170 g CO2e/km, respectively) related to transportation sector. By 2030, BEV usage in Korea is expected to achieve a greater emissions reduction of about 53% compared with diesel vehicles and 56% compared with gasoline vehicles. However, trade-offs are also expected because of increased particulate matter (PM) pollution, which we anticipate to increase by 84% compared with 2016 conditions. Despite these projected increases in PM emissions, increased BEV usage in Korea is expected to result in important global and local benefits through reductions of climate-changing greenhouse gas (GHG) emissions. 
    more » « less
  4. Abstract Traditional intracranial pressure (ICP) monitoring methods, using intraventricular catheters, face significant limitations, including high invasiveness, discrete data, calibration complexities, and drift issues, which hinder long‐term and stable monitoring. Here, a non‐surgical, in‐stent membrane bioelectronic system is presented for continuous and reliable ICP monitoring. This platform integrates a capacitive thin‐film sensor with a stent, enabling precise real‐time detection of pressure fluctuations directly within the dural venous sinus without requiring skull penetration or frequent recalibration. The sensor demonstrates a high sensitivity of 0.052%/mmHg and a broad, readable pressure range of 3–30 mmHg while maintaining calibration‐free and drift‐free performance. A series of in vivo studies highlight the system's superior sensitivity, rapid sampling rate, and long‐term stability compared to conventional microcatheters. Statistical analyses reveal a strong agreement between the device and clinical reference, underscoring its potential to revolutionize ICP monitoring. These advancements pave the way for broader clinical applications, minimizing complications and improving patient outcomes in neurocritical care. 
    more » « less
  5. Abstract By virtue of their native structures, tubulin dimers are protein building blocks that are naturally preprogrammed to assemble into microtubules (MTs), which are cytoskeletal polymers. Here, polycation‐directed (i.e., electrostatically tunable) assembly of tubulins is demonstrated by conformational changes to the tubulin protofilament in longitudinal and lateral directions, creating tubulin double helices and various tubular architectures. Synchrotron small‐angle X‐ray scattering and transmission electron microscopy reveal a remarkable range of nanoscale assembly structures: single‐ and double‐layered double‐helix tubulin tubules. The phase transitions from MTs to the new assemblies are dependent on the size and concentration of polycations. Two characteristic scales that determine the number of observed phases are the size of polycation compared to the size of tubulin (≈4 nm) and to MT diameter (≈25 nm). This work suggests the feasibility of using polycations that have scissor‐ and glue‐like properties to achieve “programmable breakdown” of protein nanotubes, tearing MTs into double‐stranded tubulins and building up previously undiscovered nanostructures. Importantly, a new role of tubulins is defined as 2D shape‐controllable building blocks for supramolecular architectures. These findings provide insight into the design of protein‐based functional materials, for example, as metallization templates for nanoscale electronic devices, molecular screws, and drug delivery vehicles. 
    more » « less