A5087037080- Advanced biosensing and bioanalysis techniques
- DNA and Nucleic Acid Chemistry
- Biosensors and Analytical Detection
- Advanced Nanomaterials in Catalysis
- Nanocluster Synthesis and Applications
- RNA Interference and Gene Delivery
- Gold and Silver Nanoparticles Synthesis and Applications
- RNA and protein synthesis mechanisms
- Electrochemical sensors and biosensors
- Molecular Sensors and Ion Detection
- Electrochemical Analysis and Applications
- Molecular Junctions and Nanostructures
- Carbon and Quantum Dots Applications
- Graphene and Nanomaterials Applications
- Nanoplatforms for cancer theranostics
- Nanoparticle-Based Drug Delivery
- Lipid Membrane Structure and Behavior
- Luminescence and Fluorescent Materials
- Nanopore and Nanochannel Transport Studies
- Graphene research and applications
- Metal-Organic Frameworks: Synthesis and Applications
- Analytical chemistry methods development
- Microplastics and Plastic Pollution
- Bacteriophages and microbial interactions
- Nanoparticles: synthesis and applications
University of Waterloo
2016-2025
National Institute for Nanotechnology
2015-2024
Hong Kong Eye Hospital
2020-2024
Hong Kong Polytechnic University
2024
Regional Municipality of Waterloo
2015-2021
Water Research Institute
2019
Changsha University of Science and Technology
2017-2018
Central South University
2013-2017
Institute of Nanotechnology
2016
State Council of the People's Republic of China
2015
A highly sensitive and selective colorimetric lead biosensor based on DNAzyme-directed assembly of gold nanoparticles is reported. It consists a DNAzyme its substrate that can hybridize to 5'-thio-modified DNA attached nanoparticles. The hybridization brings together, resulting in blue-colored nanoparticle assembly. In the presence lead, catalyzes specific hydrolytic cleavage, which prevents formation assembly, red-colored individual detection level be tuned several orders magnitude, from...
Apt to change color: DNA aptamers have been used assemble DNA-functionalized gold nanoparticles produce highly sensitive and selective colorimetric sensors with an instantaneous color response on addition of a substrate. The general method has shown for adenosine cocaine (see picture), but should be applicable any aptamer choice.
The combination of high metal selectivity DNAzymes with the strong distance-dependent optical properties metallic nanoparticles has presented considerable opportunities for designing colorimetric sensors ions. We previously communicated a design lead sensor based on assembly gold by Pb2+-dependent DNAzyme. However, heating to 50 °C followed cooling process ∼2 h was required observe color change. Herein we report new improved that allows fast (<10 min) detection Pb2+ at ambient temperature....
Copper is a key metal ion both in environment monitoring and biology, exposure to high concentration of copper can cause adverse health effects. Although significant progresses have been made designing fluorescent sensors for diamagnetic ions, few effective Cu2+ are known because the paramagnetic nature ion. We herein report highly sensitive selective "turn-on" sensor based on an vitro selected DNAzyme (also as catalytic DNA or deoxyribozyme). The substrate strand was labeled with...
Enzyme-mimicking nanomaterials (nanozymes) are more cost-effective and robust than protein enzymes, but they lack specificity. Herein, molecularly imprinted polymers were grown on Fe3O4 nanozymes with peroxidase-like activity to create substrate binding pockets. Electron microscopy confirmed a shell of nanogel. By imprinting an adsorbed substrate, moderate specificity was achieved neutral monomers. Further introducing charged monomers led nearly 100-fold for the over nonimprinted compared...
The mercury is rising: A DNAzyme with several thymine residues located close to the catalytic site rendered inactive. However, thymine–Hg2+–thymine interactions transform into an active enzyme. When fluorophore/quencher pairs are attached, can be converted a highly sensitive and selective sensor detection limit of 2.4 nM greater than 100 000-fold selectivity over other metal ions. Supporting information for this article available on WWW under...
The attachment of thiolated DNA to gold nanoparticles (AuNPs) has enabled many landmark works in nanobiotechnology. This conjugate chemistry is typically performed using a salt-aging protocol where, the presence an excess amount DNA, NaCl gradually added increase loading over 1-2 days. To functionalize large AuNPs, surfactants need be used, which may generate difficulties for downstream biological applications. We report herein novel method pH 3.0 citrate buffer complete process few minutes....
Abstract Uranium is a key element in the nuclear industry, but its unintended leakage has caused health and environmental concerns. Here we report sp 2 carbon-conjugated fluorescent covalent organic framework (COF) named TFPT-BTAN-AO with excellent chemical, thermal radiation stability synthesized by integrating triazine-based building blocks amidoxime-substituted linkers. shows an exceptional UO 2+ adsorption capacity of 427 mg g −1 attributable to abundant selective uranium-binding groups...
Being the newest member of carbon materials family, graphene possesses many unique physical properties resulting is a wide range applications. Recently, it was discovered that oxide can effectively adsorb DNA, and at same time, completely quench adsorbed fluorophores. These make possible to prepare DNA-based optical sensors using oxide. While practical analytical applications are being demonstrated, fundamental understanding binding between DNA in solution received relatively less attention....
Here, we report a catalytic beacon sensor for uranyl (UO 2 2+ ) based on an in vitro -selected UO -specific DNAzyme. The consists of DNA enzyme strand with 3′ quencher and substrate ribonucleotide adenosine (rA) the middle fluorophore at 5′ ends, respectively. presence causes cleavage rA position release thus dramatic increase fluorescence intensity. has detection limit 11 parts per trillion (45 pM), dynamic range up to 400 nM, selectivity >1-million-fold over other metal ions. most...
Colorimetric uranium sensors based on uranyl (UO22+) specific DNAzyme and gold nanoparticles (AuNP) have been developed demonstrated using both labeled label-free methods. In the method, a uranyl-specific was attached to AuNP, forming purple aggregates. The presence of induced disassembly functionalized AuNP aggregates, resulting in red individual AuNPs. Once assembled, such "turn-on" sensor is highly stable, works single step at room temperature, has detection limit 50 nM after 30 min...
Mercury is a highly toxic environmental pollutant with bioaccumulative properties. Therefore, new materials are required to not only detect but also effectively remove mercury from sources such as water. We herein describe polyacrylamide hydrogel-based sensor functionalized thymine-rich DNA that can simultaneously and Detection achieved by selective binding of Hg2+ between two thymine bases, inducing hairpin structure where, upon addition SYBR Green I dye, green fluorescence observed. In the...
Using nanomaterials to achieve functional enzyme mimics (nanozymes) is attractive for both applied and fundamental research. Laccases are multicopper oxidases highly important biotechnology environmental remediation. In this work, we report an exceptionally simple yet laccase mimic based on guanosine monophosphate (GMP) coordinated copper. It forms amorphous metal-organic framework (MOF) material. The ratio of copper GMP 3:4 as determined by isothermal titration calorimetry. has excellent...
While nanoparticle solutions cannot freeze in general, they may remain stable the presence of polymer stabilizers. We herein communicate that gold nanoparticles (AuNPs) are thiolated DNA after a freeze–thaw cycle. The is conjugated to AuNPs during freezing without additional reagents and conjugation can be completed few minutes. More importantly, density 20–30% higher than prepared by typical salt-aging method. By lowering temperature, hybridization also promoted, allowing construction...
Hydrogen peroxide (H2O2) is a key molecule in biology. As byproduct of many enzymatic reactions, H2O2 also popular biosensor target. Recently, interfacing with inorganic nanoparticles has produced number nanozymes showing peroxidase or catalase activities. CeO2 nanoparticle (nanoceria) classical nanozyme. Herein, fluorescently labeled DNA used as probe, and can readily displace adsorbed from nanoceria, resulting over 20-fold fluorescence enhancement. The displacement mechanism instead...
The interaction between DNA and inorganic surfaces has attracted intense research interest, as a detailed understanding of adsorption desorption is required for microarray optimization, biosensor development, nanoparticle functionalization. One the most commonly studied gold due to its unique optical electric properties. Through various surface science tools, it was found that thiolated can interact with not only via thiol group but also through bases. Most previous work been performed...
A quick plunge: By using lateral flow devices as a platform to separate aptamer-assembled nanoparticle (NP) aggregates, highly sensitive and selective colorimetric sensors were constructed that mimic litmus paper tests. Detection of cocaine in serum was also realized.