An ultrasensitive electrogenerated chemiluminescence-based immunoassay for specific detection of Zika virus

Zika virus (ZIKV) is a globally emerging mosquito-transmitted flavivirus that can cause severe fetal abnormalities, including microcephaly. As such, highly sensitive, specific, and cost-effective diagnostic methods are urgently needed. Here, we report a novel electrogenerated chemiluminescence (ECL)-based immunoassay for ultrasensitive and specific detection of ZIKV in human biological fluids. We loaded polystyrene beads (PSB) with a large number of ECL labels and conjugated them with anti-ZIKV monoclonal antibodies to generate anti-ZIKV-PSBs. These anti-ZIKV-PSBs efficiently captured ZIKV in solution forming ZIKV-anti-ZIKV-PSB complexes, which were subjected to measurement of ECL intensity after further magnetic beads separation. Our results show that the anti-ZIKV-PSBs can capture as little as 1 PFU of ZIKV in 100 μl of saline, human plasma, or human urine. This platform has the potential for development as a cost-effective, rapid and ultrasensitive assay for the detection of ZIKV and possibly other viruses in clinical diagnosis, epidemiologic and vector surveillance, and laboratory research

Chapter 3: Efficient ECL Luminophores

Two classes of electrogenerated chemiluminescence (ECL) luminophores are covered in this chapter: (1) inorganic systems including Ru(bpy)32+ and its derivatives, including cyclometalated Ir(iii) complexes and (2) organic systems including polycyclic aromatic hydrocarbons (PAHs), including organic dyes such as boron-dipyrromethene dyes. The focus will be on research papers published after 2008 dealing with highly efficient ECL luminophores that have good water solubility, sufficient electrochemical stability and suitable bio-functionality. A number of promising ECL luminophores have been reported over the past 10+ years, with extremely high ECL efficiencies that are many times larger than those of the standard Ru(bpy)32+ or 9,10-diphenylanthracene systems. Due to the fact that ECL emissions from various luminophores can span a wide range of spectra, from near UV to near infrared, advancement in ECL-based multiplexing detection and quantification is expected

Sensitive Determination of Hexamethylene Triperoxide Diamine Explosives, Using Electrogenerated Chemiluminescence Enhanced by Silver Nitrate

Sensitive detection and quantification of hexamethylene triperoxide diamine (HMTD), which is one of commonly used explosives by terrorists, was presented on the basis of electrogenerated chemiluminescence (ECL) technology coupled with silver nitrate (AgNO3) enhancement in acetonitrile at a platinum electrode. Upon anodic potential scanning, HMTD irreversibly oxidized at similar to 1.70 V vs Ag/Ag+ (10 mM) at a scan rate of 50 mV/s, and the ECL profile was coincident with the oxidation potential of HMTD in the presence of ruthenium(II) tris(bipyridine) (Ru(bpy)32+) luminophore species, which showed a half-wave potential of 0.96 V vs Ag/Ag+. The addition of small amounts of AgNO3 (0.50-7.0 mM) into the HMTD/(Ru(bpy)32+) system resulted in significant enhancement in HMTD ECL production (up to 27 times). Ibis enhancement was determined to be largely associated with NO(3)(-) and was linearly proportional to the concentrations of NO(3)(-) and Ag+ in solution. Homogeneous chemical oxidations of HMTD by electrogenerated NO.; and Ag(II) species proximity to the electrode were proposed to be responsible for the ECL enhancement. On the basis of cyclic voltammetry (CV) and CV digital simulations, standard potential values of 1.79 V vs Ag/Ag+ (or 1.98 V vs NHE) and 1.82 V vs Ag/Ag+ (or 2.01 V vs NHE) were estimated for Ag(II)/Ag(I) and NO(3)(center dot)/NO(3)(-) couples, respectively. A detection limit of 50 μM of HMTD was achieved with the current technique, which was 10 times more sensitive than that reported previously, which was based on a high-performance liquid chromatography/Fourier transform infrared (HPLC/FT-IR) detection method

Sensitive Determination of Triacetone Triperoxide Explosives Using Electrogenerated Chemiluminescence

Sensitive and selective detection and quantification of high explosive triacetone triperoxide (TATP) with electrogenerated chemiluminescence (ECL) at a glassy carbon electrode in water acetonitrile solvent mixture were reported. In the presence of ruthenium(II) tris(bipyridine), TATP or hydrogen peroxide derived from TATP via UV irradiation or acid treatment produced ECL emissions upon cathodic potential scanning. Interference from hydrogen peroxide on TATP detection was eliminated by pretreatment of the analyte with catalase enzyme. Selective detection of TATP from hexamethylene triperordde diarnine (HMTD, another common peroxide-based explosive) was realized by comparing ECL responses obtained from the anodic and the cathodic potential scanning; TATP produced ECL upon cathodic potential scanning only, whereas HMTD produced ECL upon both cathodic and anodic potential scanning. The hydroxyl radical formed after the electrochemical reduction of TATP was believed to be the key intermediate for ECL production, and its stability was strongly dependent on the solution composition, which was verified with electron paramagnetic resonance spectroscopy. A detection limit of 2.5 mu M TATP was obtained from direct electrochemical reduction of the explosive or hydrogen peroxide derived from TATP in 70/30% (v/v) water-acetonitrile solutions, which was similar to 400 times lower than that reported previously based on liquid chromatography separation and Fourier transform infrared detection

Photoelectrochemical Studies on Earth Abundant Pentanickel Polyoxometalates as Co-Catalysts for Solar Water Oxidation

The present contribution reports results from photoelectrochemical studies on anatase TiO2 photoanodes for solar water oxidation in the presence of an earth abundant homogeneous pentanickel silicotungstate molecular water oxidation catalyst K10H2[Ni5(OH)6(OH2)3(Si2W18O66)]·34H2O (Ni5-POM). Highly robust anatase TiO2 thin films were prepared in situ on fluorine-doped tin oxide glass (F : SnO2 or FTO) by spin coating and thermal annealing. The as-prepared films were characterized by scanning electron microscopy, energy dispersive X-ray analysis, and UV-vis spectroscopy. Under simulated solar irradiation, a maximum photocurrent of 0.20 mA cm−2 was obtained from FTO/TiO2 photoanodes in the presence of 20 μM Ni5-POM-0.050 M pH 9.0 borate buffer electrolyte at 0.70 V vs. Ag/AgCl (3.0 M KCl), which was a 2.3 times increase in photocurrent as compared to that without using the Ni5-POM catalyst. The use of the catalyst also significantly shifted the onset potential of water oxidation to a much negative potential value with respect to −0.2 V vs. Ag/AgCl. As verified by electrochemical impedance spectroscopy, the above results could be attributed to the effect of the catalyst on decreasing electron–hole recombination and facilitating the hole utilization rate on the semiconductor TiO2–electrolyte interface upon light illumination. Dissolved oxygen produced from the FTO/TiO2–Ni5-POM system was detected with an oxygen sensor. This is the first report on the use of the homogeneous water oxidation catalyst Ni5-POM as a functional co-catalyst for photoelectrochemical water oxidation with semiconductor photoanodes

Method for the detection of biological molecules using a two particle complex

Methods, compositions and kits for detecting analytes of interest in a sample using electrogenerated chemiluminescence are provided. Compositions comprising at least one solid support that entraps or contains an electrogenerated chemiluminescent moiety also provided.Board of Regents, University of Texas Syste

Examination of Electron Transfer Through DNA Using Electrogene Rated Chemiluminescence

Three aminoalkanethiols that have large electron-transfer rate constants, SH−(CH2)n−NH2 (n = 6, 8, and 11), were individually self-assembled on Au electrodes, followed by covalent attachment of tris(2,2′-bipyridyl)ruthenium(II) (Ru(bpy)32+) moieties onto the end of the thiols. Two separate electrogenerated chemiluminescence (ECL) waves were observed upon anodic potential scanning from 0 to 1.40 V vs Ag/AgCl (3 M KCl) over the electrode placed in 0.10 M tri-n-propylamine (TPrA)/0.10 M phosphate buffer (pH 7.4) solution. The first ECL wave, located at ∼0.88 V vs Ag/AgCl, was associated with the direct oxidation of TPrA at the electrode, and the second ECL wave, located at ∼1.12, 1.22, and 1.35 V vs Ag/AgCl for n = 6, 8, and 11, respectively, was directly related to the oxidation of the tethered Ru(bpy)32+ species. The electron transfer behavior through DNA was examined at Au electrodes, which were covalently immobilized with 15-mer and 20-mer single-stranded (ss) DNA, respectively, and then hybridized with the relevant complementary ssDNA tagged with Ru(bpy)32+ ECL labels. Under the same experimental conditions described above for Au/aminoalkanethiol-Ru(bpy)32+ studies, both double-stranded (ds) DNA displayed similar ECL responses, with the first ECL peak at ∼0.88 V and the second one at ∼1.22 V vs Ag/AgCl. No peak potential shift for the second ECL wave and no impact of the dsDNA on the entire electron transfer processes were observed, suggesting that complementary dsDNA helical structures can transfer electrons at a very large rate constant and that dsDNA studied were very conductive. In contrast, an electrode attached with 15-mer ssDNA-Ru(bpy)32+ did not show the second ECL wave, implying that ssDNA was not electronically conductive

DEM technic achievement and application in ERP(动态企业建模技术实现及其在ERP中的应用)

本文介绍了动态企业建模的原理、技术实现以及在ERP中的应用。重点论述了利用COM组件来建立企业业务模型