Bio-X Frontiers in Interdisciplinary Biosciences Seminar, "Discerning Rare Disease Biomarkers by Micro- and Nanotechnologies"

Frontiers in Interdisciplinary Biosciences Seminar

Speaker: Jeff Tza-Huei Wang, Professor of Mechanical Engineering and Biomedical Engineering, Johns Hopkins University

Seminar Title: “Discerning Rare Disease Biomarkers by Micro- and Nanotechnologies”

Hosted by: Joseph Liao, Department of Urology

Genomic analysis of biomarkers, including genetic markers such as point mutations and epigenetic markers such as DNA methylation, has become a central theme in modern disease diagnosis and prognosis. Recently there is an increasing interest in using confocal single-molecule spectroscopy (SMS) for genomic detection. The driving force not only comes from its ultrahigh sensitivity that allows detection of low-abundance nucleic acids without the need for amplification but also from its potential in achieving high-accuracy quantification of rare targets via single-molecule sorting. Semiconductor quantum dots (QDs) also show a great promise for biomarker analysis. The unique photophysical properties of semiconductor quantum dots (QDs) such as high quantum yield and photostability make them ideal for use as spectral labels and luminescent probes. QDs also make excellent donors to pair with organic dyes in the fluorescence resonance energy transfer (FRET) process due to the features of narrow emission spectra and small Stokes shift. This enables FRET with minimal direct acceptor excitation and donor-acceptor crosstalk, thereby permitting the design of FRET molecular sensors with extremely low intrinsic fluorescence backgrounds necessary for detecting biomolecular targets at low abundance. On the other hand, microfluidic technologies offer an exciting opportunity to realize the use of biomarkers in routine clinical settings via the development of miniaturized diagnostic systems. These platforms may function as portable bench-top environments that dramatically shorten the transition of a bench-top assay into a point-of-care format. Dr. Wang’s group has developed highly sensitive, quantitative and clinically relevant technologies for analysis of genomic markers based on the convergence of SMS, microfluidic manipulations, and quantum dots. Extraordinary performances of these new technologies have been exemplified by analysis of a variety of biomarkers including point mutations, DNA integrity and DNA methylation in clinical samples.