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오는 12월 20일 (목) NSI(나노응용시스템연구센터)가 마련한 세미나에 초대합니다.

이번 세미나는 특별히 Imperial College 홍종진 박사의 "Bio-inspired Approaches for Novel Devices and Applications " 와 UC Berkeley 이승욱 교수의 "Novel Opportunities in Bio-Nanoscience Using Genetically Engineered Viruses" 를 동시 진행할 예정이오니 관심있는 분들의 많은 참여를 바랍니다.

     ▶ 일 시 : 2007. 12. 20 (목) 10:00-12:00
     ▶ 장 소 : 서울대학교 39동 B103호 다목적 회의실
     ▶ 등 록 : 무료참석

Talk (1) * 2007. 12. 20 (목) 10:00-11:00
주  제 * Bio-inspired Approaches for Novel Devices and Applications  
연  사 * Jongin Hong (Ph.D., Imperial College)


Talk (2) * 2007. 12. 20 (목) 11:00-12:00
주  제 * Novel Opportunities in Bio-Nanoscience Using Genetically Engineered Viruses
연  사 * Seung-Wuk Lee (Professor, UC Berkeley)


▶Abstract - Jongin Hong

Biological structures and constructions are always amazing due to their high degree of sophistication and miniaturization containing multiple functions and abilities to comply with numerous demands, sometimes contradicting demands. Especially, micro- and nanoscale structures in nature have observed and they offer the clue of technologically unrealized structures and design protocols. In this presentation, I will review biological structures and constructions that are found in nature and the current status of bio-inspired approaches for novel devices and application. In the first part of my talk, I will introduce newly developed nano/microfabrication techniques to realize these structures including solid-state nanopores inspired by biological nanopores, engineered surfaces inspired by lotus leaf and insect wing and photonic structures and their applications. In the second part of my talk, I will talk about a solid-state nanopore-based single molecule detection technique and the possibility of high-throughput, parallel optical detection at the single-molecule level. I will show recent numerical assessment to design the solid-state nanopore in terms of light propagation, distribution of electromagnetic fields and light attenuation characteristics as well. In the third part of my talk, I will show experimental observations of the micro- and nanoscale structures on the wings of insects that help in enhancing the hydrophobicity and compare them to the surfaces with microscale pillars fabricated on a silicon wafer with hydrophobic coatings. I will discuss about the transition from Cassie-Baxter to Wenzel states on both surfaces and other functions of multiscale hierarchical structures on insect wings as well. Finally, I would like to briefly introduce bacteria actuation, sensing and transport (BAST) at micro/nanoscale and have the time to discuss about future challenges in bio-inspired approaches.


▶Abstract - Seung-Wuk Lee

A fundamental challenge in bio-nanoscience is to identify an active building block that can perform highly selective functions with remarkable precision based on specific recognition, programmable self-assembly, and non-toxic biocompatibility. Biological building blocks, such as DNA, peptides, and lipids, have been utilized to create vesicles, nanofibers, nanotubes, and two-dimensional synthetic hierarchical structures. By responding to external stimuli, artificial DNA conjugated with nanoparticles and peptide amphiphiles can self-assemble in reversible patterns to form hierarchical nanostructures and perform specific functions. However, their functions and precision are still not comparable to those of biological systems such as bones, brittle stars, abalone shells, and diatoms, which can orchestrate remarkable spatial and temporal control on both the nanometer and micrometer scales during the mineralization process. Identifying potential functional nanoscale basic buildings block from living systems is still challenging because of long encrypted peptides and genes.

In my seminar, I will introduce emerging multidisciplinary research field which uses genetically engineered viruses to build various electronic and medical materials and devices. The filamentous viruses, which are the basic building blocks of the self-ordering system, were selected using phage display for their specific recognition moieties of target material surfaces. M13 viruses coupled with ZnS nanocrystals spontaneously formed a self-supporting hybrid film with extended smectic liquid crystalline ordering over microns. Periodic domains were continuously propagated over a distance of centimeters. Anti-streptavidin viruses, which can specifically bind to streptavidin, were conjugated with many nanomaterials (Au, fluorescein, and phycoerythrin) and used to modulate the nanomaterials in the self-assembled virus system. The resulting virus composite films had chiral smectic C structures due to the helical surface of the M13 virus.  I will also introduce  virus-based biomedical material design for hard and soft tissue regeneration as well.