Browsing University of Waterloo by Author "Huang, Po-Jung Jimmy"
Now showing items 1-20 of 42
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Adsorption and Desorption of DNA on Graphene Oxide Studied by Fluorescently Labeled Oligonucleotides
Wu, Marissa; Kempaiah, Ravindra; Huang, Po-Jung Jimmy; Maheshwari, Vivek; Liu, Juewen (American Chemical Society, 2011-03-15)Being the newest member of the carbon materials family, graphene possesses many unique physical properties resulting is a wide range of applications. Recently, it was discovered that graphene oxide can effectively adsorb ... -
Aptamer-based biosensors for biomedical diagnostics
Zhou, Wenhu; Huang, Po-Jung Jimmy; Ding, Jinsong; Liu, Juewen (Royal Society of Chemistry, 2014-06-07)Aptamers are single-stranded nucleic acids that selectively bind to target molecules. Most aptamers are obtained through a combinatorial biology technique called SELEX. Since aptamers can be isolated to bind to almost any ... -
Assembly of DNA-Functionalized Gold Nanoparticles with Gaps and Overhangs in Linker DNA
Smith, Brendan D.; Dave, Neeshma; Huang, Po-Jung Jimmy; Liu, Juewen (American Chemical Society, 2011-04-28)DNA-directed assembly of gold nanoparticles (AuNPs) has been extensively studied because of its important applications in analytical chemistry, materials science, and nanomedicine. In a typical system, two DNA-functionalized ... -
Attaching DNA to Nanoceria: Regulating Oxidase Activity and Fluorescence Quenching
Pautler, Rachel; Kelly, Erin Y.; Huang, Po-Jung Jimmy; Cao, Jing; Liu, Biwu; Liu, Juewen (American Chemical Society, 2013-08-14)Cerium oxide nanoparticles (nanoceria) have recently emerged as a nanozyme with oxidase activity. In this work, we present a few important interfacial properties of nanoceria. First, the surface charge of nanoceria can be ... -
Biochemical Characterization of a Lanthanide-Dependent DNAzyme with Normal and Phosphorothioate-Modified Substrates
Vazin, Mahsa; Huang, Po-Jung Jimmy; Matuszek, Zaneta; Liu, Juewen (American Chemical Society, 2015-10-06)A trivalent lanthanide (Ln3+)-dependent RNA-cleaving DNAzyme, Ce13d, was recently isolated via in vitro selection. Ce13d is active in the presence of all Ln3+ ions. Via introduction of a single phosphorothioate (PS) ... -
Citrate inhibition of cisplatin reaction with DNA studied using fluorescently labeled oligonucleotides: implication for selectivity towards guanine
Wang, Feng; Huang, Po-Jung Jimmy; Liu, Juewen (Royal Society of Chemistry, 2013-10-21)The reaction between cisplatin and DNA is conveniently studied using fluorescently labeled oligonucleotides and gel electrophoresis; as an example of application, the inhibition of this reaction by citrate is demonstrated, ... -
A Cleavable Molecular Beacon for Hg2+ Detection based on Phosphorothioate RNA Modifications
Huang, Po-Jung Jimmy; Wang, Feng; Liu, Juewen (American Chemical Society, 2015-06-10)Mercury is a highly toxic heavy metal, and detection of Hg2+ by biosensors has attracted extensive research interest in the past decade. In particular, a number of DNA-based sensing strategies have been developed. Well-known ... -
Comparison of Graphene Oxide and Reduced Graphene Oxide for DNA Adsorption and Sensing
Lu, Chang; Huang, Po-Jung Jimmy; Liu, Biwu; Ying, Yibin; Liu, Juewen (American Chemical Society, 2016-10-18)Fluorescently labeled DNA adsorbed on graphene oxide (GO) is a well-established sensing platform for detecting a diverse range of analytes. GO is a loosely defined material and its oxygen content may vary depending on the ... -
Covalent linking DNA to graphene oxide and its comparison with physisorbed probes for Hg2+ detection
Lu, Chang; Huang, Po-Jung Jimmy; Ying, Yibin; Liu, Juewen (Elsevier, 2016-05-15)Graphene oxide (GO) has attracted extensive research interest as a platform for DNA adsorption and biosensor development. While most researchers use simple physisorption of fluorescently labeled DNA, covalent sensors are ... -
Degradable starch nanoparticle assisted ethanol precipitation of DNA
Ip, Alexander C-F.; Tsai, Tsung Hao; Khimji, Imran; Huang, Po-Jung Jimmy; Liu, Juewen (Elsevier, 2014-04-18)Precipitation of DNA from a large volume of aqueous solution is an important step in many molecular biology and analytical chemistry experiments. Currently, this is mainly achieved by ethanol precipitation, where a long-term ... -
Desulfurization Activated Phosphorothioate DNAzyme for the Detection of Thallium
Huang, Po-Jung Jimmy; Vazin, Mahsa; Liu, Juewen (American Chemical Society, 2015-10-20)Thallium (Tl) is a highly toxic heavy metal situated between mercury and lead in the periodic table. While its neighbors have been thoroughly studied for DNA-based sensing, little is known about thallium detection. In this ... -
Dissociation and Degradation of Thiol-Modified DNA on Gold Nanoparticles in Aqueous and Organic Solvents
Bhatt, Nishi; Huang, Po-Jung Jimmy; Dave, Neeshma; Liu, Juewen (American Chemical Society, 2011-05-17)Gold nanoparticles functionalized with thiol-modified DNA have been widely used in making various nanostructures, colorimetric biosensors, and drug delivery vehicles. Over the past 15 years, significant progress has been ... -
Distinction of Individual Lanthanide Ions with a DNAzyme Beacon Array
Huang, Po-Jung Jimmy; Vazin, Mahsa; Lin, Jennifer J.; Pautler, Rachel; Liu, Juewen (American Chemical Society, 2016-06-24)Developing chemical probes to distinguish each lanthanide ion is a long-standing challenge. Aside from its analytical applications, solving this problem will also enhance our knowledge in metal ligand design. Using in vitro ... -
DNA Adsorption by ZnO Nanoparticles near Its Solubility Limit: Implications for DNA Fluorescence Quenching and DNAzyme Activity Assays
Ma, Lingzi; Liu, Biwu; Huang, Po-Jung Jimmy; Zhang, Xu; Liu, Juewen (American Chemical Society, 2016-06-07)Zinc oxide (ZnO) is a highly important material, and Zn2+ is a key metal ion in biology. ZnO and Zn2+ interconvert via dissolution and hydrolysis/condensation. In this work, we explore their interactions with DNA, which ... -
DNA Adsorption, Desorption, and Fluorescence Quenching by Graphene Oxide and Related Analytical Application
Huang, Po-Jung Jimmy (University of Waterloo, 2011-09-20)Graphene is a single layer of graphite with many unique mechanical, electrical, and optical properties. In addition, graphene is also known to adsorb wide range of biomolecules including single-stranded DNA. On the other ... -
DNA-Length-Dependent Fluorescence Signaling on Graphene Oxide Surface
Huang, Po-Jung Jimmy; Liu, Juewen (Wiley, 2012-02-10)Fluorescence energy transfer to graphene oxide is studied using covalently linked DNA probes ranging from 4 to 70 base pairs. The characteristic distance and mechanism of energy transfer are reported. -
DNAzyme Hybridization, Cleavage, Degradation and Sensing in Undiluted Human Blood Serum
Zhou, Wenhu; Chen, Qingyun; Huang, Po-Jung Jimmy; Ding, Jinsong; Liu, Juewen (American Chemical Society, 2015-04-07)RNA-cleaving DNAzymes provide a unique platform for developing biosensors. However, a majority of the work has been performed in clean buffer solutions, while the activity of some important DNAzymes in biological sample ... -
A DNAzyme requiring two different metal ions at two distinct sites
Zhou, Wenhu; Zhang, Yupei; Huang, Po-Jung Jimmy; Ding, Jinsong; Liu, Juewen (Oxford University Press, 2015-12-10)Most previously reported RNA-cleaving DNAzymes require only a single divalent metal ion for catalysis. We recently reported a general trivalent lanthanide-dependent DNAzyme named Ce13d. This work shows that Ce13d requires ... -
Effects of Polyethylene Glycol on DNA Adsorption and Hybridization on Gold Nanoparticles and Graphene Oxide
Zhang, Xu; Huang, Po-Jung Jimmy; Servos, Mark R.; Liu, Juewen (American Chemical Society, 2012-10-09)Understanding the interface between DNA and nanomaterials is crucial for rational design and optimization of biosensors and drug delivery systems. For detection and delivery into cells, where high concentrations of cellular ... -
Extraction of DNA staining dyes from DNA using hydrophobic ionic liquids
Khimji, Imran; Doan, Krystina; Bruggeman, Kiara; Huang, Po-Jung Jimmy; Vajha, Puja; Liu, Juewen (Royal Society of Chemistry, 2013-05-18)The partition of oligonucleotides and DNA staining dyes into a few hydrophobic ionic liquids has been studied, where the oligonucleotides remain in the aqueous phase and all the DNA staining dyes are extracted in the ionic ...