Day 2 :
Keynote: CYBERTONGUE®, a multiplexed biosensing platform where BRET meets flow - for food diagnostic and other applications
Time : 10:00 - 10:30
Stephen Trowell completed his PhD in Visual Transduction Biochemistry at the Australian National University. In 1989, he was awarded an Australian National Research Fellowship, which he took up at CSIRO, Australia's National Research Agency, where he obtained tenure as a researcher. He is currently a Senior Principal Research Scientist and Group Leader for Innovative Bio/products. He has authored 54 full papers in international refereed journals and is inventor on 15 patent families. He has served on the Editorial Board of Bioinspiration and Biomimetics since 2010 and is a recipient of CSIROs Newton-Turner career award.
At the same time as the global supply chain for food and food ingredients is diversifying, tolerance for food risk is decreasing and demands for timeliness and cost minimization are intensifying. Current food diagnostic technologies are mainly focused on microbial safety but quality, process ability and chemical composition are increasingly important reasons for testing food. Rather than competing with gold standard analytical methods in accredited centralized testing laboratories, we set out to develop a biosensor platform that can provide rapid, real-time or continuous measurements of a range of different analytes in food, to inform the decisions of food producers and processors. The resulting CYBERTONGUE® technology platform uniquely combines three features. 1) The availability of a diverse repertoire of biosensors, all of which transduce a biochemical event into a photonic signal, using bioluminescence resonance energy transfer (BRET), with profound advantages over competing approaches. 2) The biosensors are used in the fluid phase, i.e., they are not fixed to a surface but mix with the sample on a microfluidic chip and are continuously replenished, and avoiding problems of sensor drift and slow regeneration and 3) Whilst single channel mode is the simplest, we have also demonstrated the use of a multichannel chip with different biosensors in each channel, simultaneously measuring different aspects of a single sample. The same principles can also be applied to biosensors for clinical diagnoses. I will describe the technical basis of CYBERTONGUE® technology and illustrate it with applications to measuring maltose in beer and spoilage proteases in milk.
National Chiao Tung University, Taiwan
Keynote: Amperometric biosensors for cancer maker detection using novel dumbbell-like gold-magnetite nanocomposites
Time : 10:30 - 11:00
Ruey-an Doong earned his PhD in Environmental Engineering from the National Taiwan University, Taiwan in 1992. He joined the Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan in 1994. He served as the Department Head in 2008 and Dean of the College of Nuclear Science, National Tsing Hua University in 2011. Currently, he is a Full Professor in the Institute of Environmental Engineering, National Chiao Tung University, Taiwan. His research interest lies in the areas of environmental chemistry and environmental nanotechnology.
An ultrasensitive amperometric immunosensor for the detection of cancer biomarker, -fetoprotein (AFP), was fabricated using Au/chitosan modified glassy carbon electrode (GCE) and antibody-functionalized dumbbell-like Au-Fe3O4 heterostructures as Biosensing platform and immuno-labels, respectively. To fabricate the labels, nano-Au NPs were first epitaxially grown onto Fe3O4 surface to form the dumbbell-like Au-Fe3O4 followed by conjugation of secondary antibody onto Au surface (Au-Fe3O4-Ab2). Results showed that the GCE modified with chitosan produced high electrochemical response by conjugation of more Au-Ab1 and the dumbbell-like Au-Fe3O4 served as a dual-probe to immobilize Ab2 onto Au as well as to reduce H2O2 by Fe3O4, resulting in the enhancement of signal amplification. The prepared Au-Fe3O4/Ab2/AFP/Ab1/Au/chitosan/GCE immunosensors exhibited a good analytical performance in the presence of 10 mM H2O2 with wide dynamic range of 4 orders of magnitude (0.01–40 ng mL-1) and low detection limit of 2.3 pg mL-1. In addition, the dumbbell-like Pt-Fe3O4 nanoparticles have been used to fabricate the amperometric biosensors for detection of dopamine. The Pt-Fe3O4-based electrode is linearly dependence on dopamine concentration in the range of 10-850 M with the detection limits of 0.13-7.22 M. Results obtained in this study clearly demonstrate that the dumbbell-like metal-magnetite biosensor is a promising biosensing platform for highly sensitive detection of tumor makers and neurotransmitters.
Yonsei University, South Korea
Time : 11:00 - 11:30
Eunkyoung Kim has completed her PhD from University of Houston. She is the Director of Active Polymer Center for Pattern Integration (APCPI), an engineering research center of excellence in Korea. She has published more than 170 papers in reputed journals and was awarded the Doctor honoris causa of École Normale Supérieure de Cachan.
The photothermal conversion in conductive polymers has been attracted as the important phenomena to generate heat for bio engineering as well as energy harvesting. In particular, the harvesting of living cell and cell sheet via NIR photothermal effect is of great interest in wide research area including cell therapy, transplantation, tissue engineering and regenerative medicine. In our experiments, the local heating of conductive polymer film or nanoparticles, via NIR photothermal effect of polymers, allowed to stimuli proteins that are interfaced between adherent cells and polymer surface. A collagen layer was coated on a conductive polymer surface prepared from poly (3, 4-ethylenedioxythiophene)s (PEDOT). The NIR photothermal effect of PEDOT surface induced unfolding of collagen triple helices, yielding soluble collagen structures. This dissociation of collagens provided a fast harvesting method of a living cell sheet, within few minutes of NIR irradiation. Using a systematic optical set-up, harvesting of a large area cell sheet and patterned cell sheets were achieved. Effect of the structure and composition of the conducting polymer films on the photothermal conversion as well as harvesting of cell sheets will be discussed.