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Journal ArticleDOI

The application of a G-quadruplex based assay with an iridium(iii) complex to arsenic ion detection and its utilization in a microfluidic chip

18 Jan 2017-Journal of Materials Chemistry B (The Royal Society of Chemistry)-Vol. 5, Iss: 3, pp 479-484
TL;DR: The iridium(iii) complex 1 was synthesized and employed in constructing an assay which is based on a G-quadruplex for detecting arsenic ions in aqueous solution and showed high selectivity towards arsenic ions over other metal ions.
Abstract: In this work, the iridium(iii) complex 1 was synthesized and employed in constructing an assay which is based on a G-quadruplex for detecting arsenic ions in aqueous solution. The assay achieved a detection limit of 7.6 nM (ca. 0.57 μg L-1) and showed high selectivity towards arsenic ions over other metal ions. Additionally, the assay could function in natural water and a simple microfluidic chip was used to investigate the potential of this platform for real-time detection.
Citations
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Journal ArticleDOI
TL;DR: The recent development and applications of aptamer sensors (aptasensors) based-on nanomaterial for arsenic detection are reviewed, in particular with emphasis on the works using optical and electrochemical technologies.

95 citations

Journal ArticleDOI
TL;DR: This review of works from the past 20 years in which inorganic chemistry and nanotechnology were implemented in each of the core components that make up a diagnostic test highlights the detection of nucleic acids at the point of care as an emerging application of inorganic Chemistry.
Abstract: Infectious diseases claim millions of lives each year. Robust and accurate diagnostics are essential tools for identifying those who are at risk and in need of treatment in low-resource settings. Inorganic complexes and metal-based nanomaterials continue to drive the development of diagnostic platforms and strategies that enable infectious disease detection in low-resource settings. In this review, we highlight works from the past 20 years in which inorganic chemistry and nanotechnology were implemented in each of the core components that make up a diagnostic test. First, we present how inorganic biomarkers and their properties are leveraged for infectious disease detection. In the following section, we detail metal-based technologies that have been employed for sample preparation and biomarker isolation from sample matrices. We then describe how inorganic- and nanomaterial-based probes have been utilized in point-of-care diagnostics for signal generation. The following section discusses instrumentation for signal readout in resource-limited settings. Next, we highlight the detection of nucleic acids at the point of care as an emerging application of inorganic chemistry. Lastly, we consider the challenges that remain for translation of the aforementioned diagnostic platforms to low-resource settings.

76 citations


Cites background from "The application of a G-quadruplex b..."

  • ...[137] [138] [139] 141, 142, 160 Ligands in these cyclometalated Ir (III) complexes (e.g., deprotonated 2-phenylpyridine) demonstrate strong σ-donor effects, which significantly increase the energy of the 1 MC (metal-centered) excited state (i.e., the ligand field stabilization energy) that gives rise to nonradiative decay pathways....

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Journal ArticleDOI
Yong Yao1, Huijie Li1, Dan Wang1, Cuiling Liu1, Chunsun Zhang1 
25 Sep 2017-Analyst
TL;DR: The presented ECL platform has the potential to be applied to non-invasively detect a variety of analytes of medical interest, and the ECL biosensor is successfully applied for the determination of lactate in human saliva.
Abstract: Cloth fabrics and smartphones have become the two things people are most familiar with. Particularly, smartphones are used as portable personal computers, revolutionizing communication and lifestyle. Here, screen-printing technology is applied to fabricate carbon electrodes and electrochemical chambers on a single hydrophilic cloth, while the cloth-based electrochemiluminescence (ECL) signals are read out by using an inexpensive smartphone. Therefore, the ECL detection is available in both low-cost disposable sensors and a portable format, which may be very suitable to be used as a non-invasive monitoring tool for medical diagnostics. As a proof-of-principle, lactate oxidase is immobilized onto the working electrode for the lactate measurement. Under optimized conditions, the lactate levels can be quantified over the range of 0.05-2.5 mM, with a detection limit of 0.035 mM and the relative standard deviations of 4.7%, 5.2% and 5.0% for 0.05, 0.5 and 2.5 mM lactate (n = 5). In addition, the proposed biosensor has an acceptable stability and selectivity. Finally, the ECL biosensor is successfully applied for the determination of lactate in human saliva. These results show that the presented ECL platform has the potential to be applied to non-invasively detect a variety of analytes of medical interest.

62 citations

Journal ArticleDOI
TL;DR: In this article, a simple sensor based on Glutathione (GSH) was developed for the green synthesis of surface-passivated carbon dots from edible prickly pear cactus fruit as the carbon source by a one-pot hydrothermal route.
Abstract: Efforts were made to develop a simple new approach for the green synthesis of surface-passivated carbon dots from edible prickly pear cactus fruit as the carbon source by a one-pot hydrothermal route. Glutathione (GSH) was passivated on the surface of the CDs to form a sensor probe, which exhibited excellent optical properties and water solubility. The prepared sensor was successfully characterized by UV-visible spectrophotometry, fluorescence spectrophotometry, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The simple sensing platform developed by the GSH-CDs was highly sensitive and selective with a “turn-off” fluorescence response for the dual detection of As3+ and ClO− ions in drinking water. This sensing system exhibited effective quenching in the presence of As3+ and ClO− ions to display the formation of metal complexes and surface interaction with an oxygen functional group. The oxygen-rich GSH-CDs afforded a better selectivity for As3+/ClO− ions over other competitive ions. The fluorescence quenching measurement quantified the concentration range as 2–12 nM and 10–90 μM with the lower detection limit of 2.3 nM and 0.016 μM for the detection of As3+ and ClO− ions, respectively. Further, we explored the potential applications of this simple, reliable, and cost-effective sensor for the detection of As3+/ClO− ions in environmental samples for practical analysis.

58 citations

Journal ArticleDOI
TL;DR: The ratiometric fluorescence nanoprobe constructed in this work exhibited high sensitivity for ssab (a dsDNA) and c-myc (a parallel G4) with a low detection limit of 0.90 and 3.31 nM, respectively and showed good selectivity to parallel G-quadruplex (G4) and double-stranded (ds) DNA over antiparallel G4 and single- Stranded DNA.
Abstract: A new carbon dot (CD)-based nanoprobe for the ratiometric fluorescence detection of DNA was constructed in this work. Thiazole orange (TO), a specific organic small molecular probe toward DNA, is covalently linked to the surface of CDs, acting as the recognition element and the fluorescence response unit. In the absence of DNA, the nanoprobe only emitted the blue fluorescence of CDs, whereas TO was almost nonfluorescent. Upon addition of DNA, a turn-on emission at 530 nm appeared and gradually enhanced along with the increasing of the target DNA, whereas the fluorescence of CDs was unchanged, which realized the ratiometric detection of the target DNA. The CD-TO nanoprobe showed good selectivity to parallel G-quadruplex (G4) and double-stranded (ds) DNA over antiparallel G4 and single-stranded DNA. Moreover, the ratiometric fluorescence nanoprobe exhibited high sensitivity for ssab (a dsDNA) and c-myc (a parallel G4) with a low detection limit of 0.90 and 3.31 nM, respectively. Additionally, the G4/hemin peroxidase activity inhibition experiment demonstrated that CD-TO bound to the G4s through the end-stacking mode.

47 citations

References
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Journal ArticleDOI
TL;DR: Key Laboratory for Organic Electronics and Information Displays (KLOEID) and Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, Nanjing 210046, P. R. China.
Abstract: Yuming Yang,†,§ Qiang Zhao,‡,§ Wei Feng,† and Fuyou Li*,† †Department of Chemistry and State Key Laboratory of Molecular Engineering of Polymers and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433, P. R. China ‡Key Laboratory for Organic Electronics and Information Displays (KLOEID) and Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, Nanjing 210046, P. R. China.

1,999 citations

Journal ArticleDOI
TL;DR: A series of aptamers currently in development may change how nucleic acid therapeutics are perceived and will increasingly find use in concert with other therapeutic molecules and modalities.
Abstract: Nucleic acid aptamers can be selected from pools of random-sequence oligonucleotides to bind a wide range of biomedically relevant proteins with affinities and specificities that are comparable to antibodies. Aptamers exhibit significant advantages relative to protein therapeutics in terms of size, synthetic accessibility and modification by medicinal chemistry. Despite these properties, aptamers have been slow to reach the marketplace, with only one aptamer-based drug receiving approval so far. A series of aptamers currently in development may change how nucleic acid therapeutics are perceived. It is likely that in the future, aptamers will increasingly find use in concert with other therapeutic molecules and modalities.

1,707 citations

Journal ArticleDOI
TL;DR: Here the authors review studies that provided important information about conformational properties of DNA using circular dichroic (CD) spectroscopy, which significantly participated in all basic conformational findings on DNA.
Abstract: Here we review studies that provided important information about conformational properties of DNA using circular dichroic (CD) spectroscopy. The conformational properties include the B-family of structures, A-form, Z-form, guanine quadruplexes, cytosine quadruplexes, triplexes and other less characterized structures. CD spectroscopy is extremely sensitive and relatively inexpensive. This fast and simple method can be used at low- as well as high-DNA concentrations and with short- as well as long-DNA molecules. The samples can easily be titrated with various agents to cause conformational isomerizations of DNA. The course of detected CD spectral changes makes possible to distinguish between gradual changes within a single DNA conformation and cooperative isomerizations between discrete structural states. It enables measuring kinetics of the appearance of particular conformers and determination of their thermodynamic parameters. In careful hands, CD spectroscopy is a valuable tool for mapping conformational properties of particular DNA molecules. Due to its numerous advantages, CD spectroscopy significantly participated in all basic conformational findings on DNA.

1,406 citations