chung-ang university

9 ARTICLES PUBLISHED IN JoVE

JoVE Core

A Paired Bead and Magnet Array for Molding Microwells with Variable Concave Geometries

Gi-Hun Lee¹, Youngjoon Suh¹, Joong Yull Park¹

¹School of Mechanical Engineering, College of Engineering, Chung-Ang University

This manuscript introduces a robust method of fabricating concave microwells without the need for complex high-cost facilities. Using magnetic force, steel beads, and a through-hole array, several hundred microwells were formed in a 3 cm x 3 cm polydimethylsiloxane (PDMS) substrate.

Neuroscience

Measuring Synaptic Vesicle Endocytosis in Cultured Hippocampal Neurons

Seth Villarreal¹, Sung Hoon Lee^1,2, Ling-Gang Wu¹

¹National Institute of Neurological Disorders and Stroke, ²College of Pharmacy, Chung-ang University

Synaptic vesicle endocytosis is detected by light microscopy of pHluorin fused with synaptic vesicle protein and by electron microscopy of vesicle uptake.

Bioengineering

Synthesis of Multi-walled Carbon Nanotubes Modified with Silver Nanoparticles and Evaluation of Their Antibacterial Activities and Cytotoxic Properties

Youngmin Seo^*1, Chanhwi Park^*2, Jaewoo Son², Kyungwoo Lee², Jangsun Hwang², Yeonho Jo², Dohyun Lee², Muhammad Saad Khan², Sachin Ganpat Chavan², Yonghyun Choi², Dasom Kim², Assaf A Gilad³, Jonghoon Choi²

¹Center for Biomaterials, Biomedical Research Institute, Korea Institute of Science and Technology, ²School of Integrative Engineering, Chung-Ang University, ³Division of Synthetic Biology and Regenerative Medicine, Institute for Quantitative Health Science and Engineering, Michigan State University

In this study, antimicrobial nanomaterials were synthesized by acidic oxidation of multiwalled carbon nanotubes and subsequent reductive deposition of silver nanoparticles. Antimicrobial activity and cytotoxicity tests were performed with the as-prepared nanomaterials.

Bioengineering

3D Analysis of Multi-cellular Responses to Chemoattractant Gradients

Tae-Yun Kang¹, David Ellison², Sung Hoon Lee¹, Andrew J. Ewald^2,3, Andre Levchenko¹

¹Department of Biomedical Engineering and Yale Systems Biology Institute, Yale University, ²Department of Biomedical Engineering, Johns Hopkins University, ³Center for Cell Dynamics and Department of Cell Biology, Johns Hopkins University

We describe a method to construct devices for 3D culture and experimentation with cells and multicellular organoids. This device allows analysis of cellular responses to soluble signals in 3D microenvironments with defined chemoattractant gradients. Organoids are better than single cells at detection of weak noisy inputs.

Bioengineering

Lab-on-a-CD Platform for Generating Multicellular Three-dimensional Spheroids

Daehan Kim¹, Gi-Hun Lee¹, Jiheum Park², Jung Chan Lee², Joong Yull Park¹

¹Department of Mechanical Engineering, Graduate School, Chung-Ang University, ²Department of Biomedical Engineering, College of Medicine, Seoul National University

We present a motor-powered centrifugal microfluidic device that can cultivate cell spheroids. Using this device, spheroids of single or multiple cell types could be easily cocultured under high gravity conditions.

JoVE Core

Elaborate Control of Inkjet Printer for Fabrication of Chip-based Supercapacitors

Seyoung Choi¹, Jihyeon Kang¹, Seohyeon Jang¹, Hojong Eom¹, Ohhyun Kwon¹, Junhyeop Shin¹, Inho Nam¹

¹School of Chemical Engineering and Materials Science, Department of Intelligent Energy and Industry, Department of Advanced Materials Engineering, Chung-Ang University

This paper provides a technique for manufacturing chip-based supercapacitors using an inkjet printer. Methodologies are described in detail to synthesize inks, adjust software parameters, and analyze the electrochemical results of the manufactured supercapacitor.

JoVE Core

Evaluating the Electrochemical Properties of Supercapacitors using the Three-Electrode System

Hojong Eom¹, Jihyeon Kang¹, Seohyeon Jang¹, Ohhyun Kwon¹, Seyoung Choi¹, Junhyeop Shin¹, Inho Nam¹

¹School of Chemical Engineering and Materials Science, Department of Intelligent Energy and Industry, Chung-Ang University

The protocol describes the evaluation of various electrochemical properties of supercapacitors using a three-electrode system with a potentiostat device.

Chemistry

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch

Myeongsu Jeong^*1, Jiyoon Park^*1, Kwonjung Lee^*1, Sunbum Kwon¹

¹Department of Chemistry, Chung-Ang University

Photoisomerization quantum yield is a fundamental photophysical property that should be accurately determined in the investigation of newly developed photoswitches. Here, we describe a set of procedures to measure the photoisomerization quantum yield of a photochromic hydrazone as a model bistable photoswitch.

Engineering

Synthesizing a Gel Polymer Electrolyte for Supercapacitors, Assembling a Supercapacitor Using a Coin Cell, and Measuring Gel Electrolyte Performance

Ohhyun Kwon¹, Jihyeon Kang¹, Seohyeon Jang¹, Seyoung Choi¹, Hojong Eom¹, Junhyeop Shin¹, Jong-Kwon Park¹, Soomin Park², Inho Nam¹

¹School of Chemical Engineering and Materials Science, Department of Intelligent Energy and Industry, Department of Advanced Materials Engineering, Chung-Ang University, ²School of Energy, Materials and Chemical Engineering, Korea University of Technology and Education

We present a protocol to test the electrochemical and physical properties of a supercapacitor gel polymer electrolyte using a coin cell.