Come see what Boise State has to offer Chemistry and BioChemistry Majors

November 30, 2017

The Chemistry Department welcomes Jeunghoon Lee, PhD from Boise State University to the BYU-Idaho Campus.  Dr. Lee will be presenting a seminar for all Chemistry, Biochemistry, Chemistry Education Majors and Faculty.  The title of his seminar is Highly Sensitive Visual Detection of Nucleic Acids using Gold Nanoparticles and DNA Reaction Networks.

The seminar will be held in the Romney Building, Room 277, from 2:00-3:00 pm.

Refreshments will be served.

Dr Jeunghoon Lee

Highly Sensitive Visual Detection of Nucleic Acids using Gold Nanoparticles and DNA Reaction Networks

Jeunghoon Lee Department of Chemistry and Biochemistry,Micron School of Materials Science & Engineering Boise State University; Boise, ID 83725 USA              

Unique optical properties of gold nanoparticles makes them an ideal material for inexpensive and sensitive colorimetric sensors when engineered to bind to specific molecules.1 When integrated with a DNA reaction network, the sensitivity of a colorimetric sensor driven by gold nanoparticle aggregation was enhanced by several fold.2 Nanoparticle aggregation-driven sensors, however, suffers from fundamental sensitivity limits and relatively slow kinetics. A colorimetric sensing system driven by catalytic disassembly of nanoparticles can overcome such limits because only free nanoparticles are used as the optical signal and diffusion of unbound DNA strands is faster than that of nanoparticle-bound strands. We report the design and performance of a catalytic disassembly of nanoparticles driven by an autocatalytic network developed by Zhang et al.3 As shown in Figure 1, the substrate complexes of the autocatalytic network act as the linkage between gold nanoparticles and polymer microbeads. As the network operates in presence of the catalyst, the substrate dissociates into the output and waste, which drives the disassembly of nanoparticle aggregates. Nanoparticle-coated polymer beads were assembled first to control the extent of aggregation and facilitate diffusion of the catalyst and fuel strands to the substrate complex.  The effect of surface density of DNA strands, and ionic strength will be discussed in further detail. We will also incorporate leak reduction strategies using mismatched fuel strands4 to enhance the sensitivity of the nanoparticle disassembly. Acknowledgments: This project was supported in part by the: (1) National Science Foundation (CBET, 1706065), (2) NIH Grant No. P20 GM103408 from the Idaho INBRE Program, (3) American Chemical Society Project SEED, and (4) Boise State University. References (1)        Storhoff, J. J.; Elghanian, R.; Mucic, R. C.; Mirkin, C. A.; Letsinger, R. L. J. Am. Chem. Soc. 1998, 120, 1949. (2)        Huttanus, H. M.; Graugnard, E.; Yurke, B.; Knowlton, W. B.; Kuang, W.; Hughes, W. L.; Lee, J. Biosens. Bioelectron. 2013, 50, 382. (3)        Zhang, D. Y.; Turberfield, A. J.; Yurke, B.; Winfree, E. Science 2007, 318, 1121. (4)        Olson, X.; Kotani, S.; Padilla, J. E.; Hallstrom, N.; Goltry, S.; Lee, J.; Yurke, B.; Hughes, W. L.; Graugnard, E. ACS Synth. Biol. 2017, 6, 84.