California NanoSystems Institute

Joint Symposium on Nano-scale Research
into Biosenors, Biomaterials, and Nanotoxicology

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Toru Asahi Department of Life Science & Medical Bio-Science, School of Advanced Science and Engineering, Waseda University, Japan	"Chiral Recognition for Bio-Related Materials" Aiming at an application of the large-scale chiral surface of amino acid films to chiral sensor devices, which are useful for chiral recognition for biomolecules or medicine, we attempted to deposit amino acid films using a conventional vacuum evaporation method. After lots of preliminary experiments under different conditions, we could vapor-deposit homogeneous films of L- and D-isoleucine. To our surprise, they exhibited optical anisotropy in the film plane, which was confirmed with a polarizing microscope. Furthermore, we investigated quantitatively optical anisotropy as physical parameters; linear birefringence (LB), linear dichroism (LD), circular dichroism (CD), and circular birefringence (CB), of the evaporated film using the generalized high accuracy universal polarimeter (G-HAUP), which enabled us to make completely simultaneous measurements of LB, LD, CD, and CB in anisotropic solid materials in 1996. The GHAUP revealed that the anisotropic films of isoleucine showed unique behaviors of LB, CD, and CB, but that LD did not occur in the wavelength longer than 400 nm. Thus we succeeded in depositing anisotropic chiral films of isoleucine by vacuum evaporation.
Yoshikuni Edagawa Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, Japan	"Multimodal Manipulating System for Individual Single Cells on Microtechnology" Single cell manipulating system has been developed for a delicate understanding of cell biology. However, the noninvasive handling of individual single cells does not yet completely succeed. We here demonstrate a manipulation system for noninvasive single cell capture and culture. This system takes a benefit of the microfluidic device, which consists of microchannels and micropockets. The mold-microfabricate channel was placed in parallel, and the cylindrical micropockets for noninvasive single cell capture were molded between the parallel channels. Single cells were dissociated and captured in micropockets when cell suspension was delivered into a microchannel. Each trapped cells were completely individual because each pocket with a narrow drain channel was capped by the captured cell and other cells passed the pocket. The fundamental mechanism of the present system was demonstrated by the simple controlling of the flow rate, which essentially delivered the pressure on each channel, and the shapes of the microfabricated device. After isolation of single cell(s), we successively tried to long-term culture of captured cell(s) on the spot. The cultivation of trapped cell(s) in the microenvironment was achieved and observed as multiplication for at least four passage numbers. Furthermore, the rupture of single cell was also achieved alternatively after single cell isolation. The lysate of each single cell, especially the nuclei and the mitochondria, was detected after the cell breakage. Taken together the unique character of microfluidic system such as laminar flow, the beneficial aspect(s) of the present system for the micropharmacological studies will be discussed.
Hiroshi Kawarada School of Fundamental Science and Engineering, Waseda University, Japan	"Nano Carbon Based Devices for Biochemical Applications" Due to their extreme properties as semiconductor, diamond and carbon nanotube are expected to be applied in not only high power and high frequency operation, but also biosensor and biochemical reactor. In diamond, we focused on surface accumulation layer appearing on a hydrogen terminated diamond surface and developed surface channel field effect transistors (FETs) operated in electrolyte solution. This type of FET is applicable in biosensors. We are also investigating carbon nanotube for electric double layer capacitor. Utilizing surface chemical bonds, diamond surfaces show a variety of unique properties, such as hydrophobicity or hydrophilicity, positively or negatively charged, conducting or nonconducting etc. These properties are stable in air or in electrolyte solution. Combining these properties, the surfaces provide a platform for biomolecule immobilization and biochemical reaction. The biomolecule immobilization by covalent bonding on diamond is extremely stable. DNA hybridization, antigen-antibody reaction can occur with an influence of modified diamond surface. When immobilized probe DNAs hybridise with target DNAs in the electric double layer, the surface holes can be induced by the increase of surface negative charge of the hybridised DNAs and detected by diamond FET operated in electrolyte solution (Solution Gate FET, SGFET). Compared with Si ISFET, the diamond SGFET has the advantages in sensitivity and stability because biomolecules can be immobilized directly on the diamond surface channel. The single nucleotide polymorphism (SNPs, one base mismatch) target DNA has been detected reproducibly. The miniaturized SGFET showing the highest FET performance operated in electrolyte solution.
Susumu Minamisawa School of Advanced Science and Engineering, Waseda University, Japan	"Prostaglandin E2 in the Ductus Arteriosus: A New Role for an Old Friend" Prostaglandin E (PGE), a potent vasodilator, plays a primary role in the patency of the ductus arteriosus (DA), a bypass artery for fetal circulation. Genetic disruption of the PGE specific-receptor EP4, however, paradoxically results in patent DA (PDA) in mice. We found that chronic EP4 stimulation significantly enhanced smooth muscle cell (SMC) migration and hyaluronic acid (HA) production in rat DA. Using immature rat DA explants, we found that intimal cushion formation (ICF) was promoted by both PKA and EPAC stimuli, which are downstream targets of EP4-cAMP pathway. Furthermore, adenovirus-mediated HAS2 gene transfer rescued the PDA phenotype of EP4-disrupted DA explants where ICF was not developed. Accordingly, EP4-cAMP signals have two essential roles in DA development, vascular dilation and ICF. Activation of PKA pathway increased transcription of the HAS2 genes and thus HA production. The PKAmediated HA accumulation promoted DA SMC migration, resulting in promoting ICF. On the other hand, EPAC acutely promoted DA SMC migration and thus ICF in rat DA. Our results imply that selective stimulation of cAMP-dependent signal pathway serves as an alternative therapeutic strategy for PDA to the current one, i.e. inhibition of PGE signaling by cyclooxygenase inhibitors.
Tetsuya Osaka Dept. of Applied Chemistry, Faculty of Science and Engineering, Waseda University, Japan	"Highly Sensitive On-Chip Sensor Devices for Medical Care" Sensing systems for biomolecules are in great demand for the fields of medical, pharmaceutical, food, and environmental sciences. To develop high-performance biosensors, the clarification and utilization of the mechanisms of bioreactions in a molecular scale are very effective. When the molecular-recognition mechanisms in a living body are applied to sensing systems, it is a promising method to use solid surfaces with functional organic monolayers as the detection/recognition parts of sensing devices. Aiming at a development of novel sensing devices, we are investigating on-chip micro-sensing devices, chiral recognition surfaces, and surfacemodified nanoparticles utilizing organic monolayer films constructed on solid surfaces. We developed a field effect transistor (FET) operating in aqueous environments for the application to the highly sensitive micro-sensing systems. Currently, practical application of micro pH sensors and DNA mismatch sensors are proceeding. We are investigating the enantioselectivity of the monolayer-modified chiral surface. Electrochemical method is utilized to detect enantioselectivity of the monolayer and to detect the enantiomer because electrochemical reactions reflect sensitively the phenomena at the electrode/liquid interface. We are also trying to prepare iron oxide magnetic nanoparticles for the application to an immune cell therapy. Controlling the size and surface affinity of the nanoparticles for efficient inclusion into lymphocytes are our main interest.
Naoya Sawamura Consolidated Research Institute for Advanced Science and Medical Care (ASMeW), Waseda University, Japan	"Elucidation of the Signal Transduction Pathway Associated with Disrupted-in-schizophrenia-1 (DISC1) Protein Function" Schizophrenia is believed to result from the interaction of environmental factors with genetic vulnerability. Disrupted-in-Schizophrenia-1 (DISC1), identified at the breakpoint of a chromosomal translocation co-segregating with major mental illness in a large Scottish family, may be an important candidate gene for psychiatric conditions. Although the function of DISC1 is still unclear, our results indicate that DISC1 may have several roles in the nucleus. The specific aim of this study is to identify the pathway that DISC1 regulates. To know the upstream signal of DISC1 and down-regulated genes by DISC1 may contribute to elucidate the molecular mechanism of schizophrenia and to screen pharmaceutical targets.
Takahiro Shinada Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, Japan	"Functional Modification of Cells by Single-Ion Implantation" Ion implantation of dopant atoms into semiconductors, typically silicon, which commonly has been used for more than 30 years to modify electrical properties in electron devices, is essential to modern integrated-circuit (IC) manufacturing. So far the semiconductor has been a priori assumed to be homogeneously doped. In the nano-scale semiconductor devices, however, the channel region will contain few dopant atoms. Discrete random distribution of dopants will cause fluctuation in the number of dopant atoms, resulting in unacceptable variations in electrical properties across the wafer. We suppressed the fluctuation and improved the device performance by single-ion implantation (SII) technique, which enables us to implant dopant ions one-by-one into a fine region until the desired number is reached. The purpose of this study is to explore an element that prevents a cancer cell from proliferating or kills it, resulting in an effective cancer treatment by employing the SII with controllability of both dopant atom number and position. In the initial stages of the research, we will modify the function of a cell by irradiating impurity ions; we will then evaluate the resulting functional modification by observing the morphology of the cell through an optical microscope and by measuring the viability of the cell. We will focus on Au ions, as Au is reported to have therapeutic effects, and we will verify the effects brought about by irradiating a cell with Au ions. Through research that tries to modify the function of a cell, we wish to develop a technique of nanomedicine, based on new ideas using the SII method, and to explore the therapeutic role of Au, where this remains unclear.
Shuichi Shoji School of Fundamental Science and Engineering, Waseda University, Japan	"Micro/Nano Fabricated Device and Systems for Chemical and Biochemical Applications" Biological cell analysis is one of the trends in MicroTotal Analysis Systems (MicroTAS) and Lab-on-a-Chip (LOC) field. Many types of cell handling and monitoring flow systems, cell counter, cell sorter etc. have been reported. Basic micro devices for future intercellar analysis are also developed using micro/nano fluidics. The fluidic behaviors in micro/nano channels of nano liter or pico liter in volume are quite important to realize good performance of these devices and systems. In order to obtain required features of the fluidic devices and systems for bioapplications, Computational Fluid Dynamics (CFD) simulation plays very important roles. Specially, for the functional chemical reaction and bioanalysis micro/nano systems, optimum design of the microchannels using CFD is indispensable. In this paper, functional droplet generation system, real time cell moniroting systems, cell and biomolecules sorting systems and biomolecular dynamics monitoring systems mainly developed in our group are described.
Haruko Takeyama School of Advanced Science and Engineering, Waseda University, 50th Bldg, Waseda University, Japan	"Application of Nano-Scale Engineered Biomagnetite to Biosensing" Biomagnetite (bacterial magnetic particles; BacMPs) isolated from the magnetic bacterium Magnetospirillum magneticum AMB-1 are small in size (50-100 nm) and are surrounded by a phospholipids bilayer membrane. BacMPs offer high technological potential since these can be conveniently manipulated with magnetic force. The thin organic membrane enveloping the individual BacMPs confers high and even dispersion in aqueous solutions compared to artificial magnetites making them ideal biotechnological materials. Furthermore, the findings in the molecular biological research for elucidation of their formation developed a superior strategy for novel new nanomaterials where functional proteins such as enzyme, antibody, and receptor were assembled on BacMPs by using proteins isolated from their membrane as anchor. These BacMPs have already been successfully used in immunoassay and for DNA detection. Furthermore, seven-transmembrane proteins, G protein-coupled receptors (GPCRs) were also successfully assembled onto BacMPs. Here we will describe application of BacMPs to several biosensing materials. Furthermore a research on a single cell analysis will be also preseted.
Hong Zhang Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, Japan	"Risk Assessment of Engineered Nanoparticles on Health and the Environment" Nanomedicine is a new emerging multidisciplinary scientific field. The bio-safety of nanomaterials is a hotspot. In our previous work, we investigated the impact of single-walled carbon nanotubes on human HEK 293 cells, and human fibroblast cells, as well as polymerase chain reaction18, showing that CNTs can inhibit cell growth or proliferation. Now we are working on the cytotoxicity of nanoparticles in human normal stem cells (umbilical cord blood cells) and monkey embryonic stem cells. As we know, stem cells especially ES stem cells are very important for our body, because they have an ability to differentiate into all cell type of tissue. The safety of nanotechnology-based materials and products on stem cells is necessary. My research focus on: 1) finding good condition for dispersion of nanoparticles within a cell culture medium and demonstrated that there are considerable interactions between the nanoparticles and the various components of the medium. 2) Co-culture and transfect the nanoparticles into the stem cells, analysis the transfectant cells viability, proliferation, apoptosis by immunostaining and flowcytometry. 3) Differentiation umbilical cord blood cells and monkey ES cells into endothelial cells, blood cells under nanoparticles existing condition. The influence of nanoparticles on early event occurring in the development of embryonic hamatopoiesis will be determined.