The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this work, we report a novel approach which employed substrate-triggered intramolecular addition-cyclization cascade to develop a highly selective fluorescent probe E)-3-(4-(1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)-1-(2-hydroxylphenyl) prop-2-en-1-one (P-OH) for NH2NH2. The new sensing mechanism of P-OH for NH2NH2 was investigated in detail by fluorescence spectroscopy, 1H NMR titration, mass...
A novel fluorescent probe (E)-3-ethyl-2-(4-hydroxystyryl)-1,1-di-methyl-1H-benzo-[e]indolium iodide (probe EDB) based on benzo[e]indolium was synthesized, which provided the simultaneous detection of SO32-/HSO3- and HSO4- ion with different emission channels. Based on the principle of ion-induced rotation-displaced H-aggregates, when treated with NaHSO4, a fluorescence enhancement at 580nm was observed...
In this paper, aldehyde-terminated ionic liquid was synthesized and used to fabricate a novel label-free electrochemical immunosensor for the determination of hepatitis B surface antigen. This sensor was formed from a gold electrode which was modified with a composite film containing the aldehyde-functionalized ionic liquid incorporated into nafion and anti-hepatitis B surface antigen antibody probes...
Biogenic amines are degradation products generated through enzymatic and microbial processes during food spoilage, which may pose a health hazard to consumers at elevated levels. Trimethylamine (TMA) is a good target for the detection of biogenic amines due to its volatility and fishy odor. In this study, we developed a stand-alone dopant-assisted positive photoionization ion mobility spectrometry...
A simple and reliable fluorescent nitrite (NO2−) probe, 2-(1H-phenanthro[9,10-d] imidazol-2-yl)aniline (PA), was rationally developed based on a novel NO2−-mediated diazozation and subsequent cyclization. The new sensing mechanism of the probe was confirmed by using NMR, IR spectra, control experiments and DFT calculations. The synthesized probe showed low pH dependence, fast and highly selective...
Sudan dyes are banned as food additives due to the carcinogenicity of their metabolites in the human body. Therefore, it is of great significance for sensitive detection of Sudan dyes. This paper reports a novel nanosensor for Sudan dyes detection based on fluorescence (FL) quenching of hexadecyl trimethyl ammonium bromide (CTAB) stabilized upconversion nanoparticles (UCNPs) through the inner filter...
In this work, a novel sulfur-containing compound with aldehyde groups was synthesized, which was used to immobilize antibodies through the covalent bonding of the aldehyde groups with amino groups, in which no additional chemical cross-linker is required. Human IgG was used as a model analyte to fabricate the electrochemical immunosensor. Using the proposed immunosensor, IgG was detected within the...
Here we report a nanosensor based on fluorescence resonance energy transfer (FRET) between upconversion nanoparticles (UCNPs) and gold nanoparticles (AuNPs) for melamine detection. The positively charged UCNPs as donor and the negatively charged AuNPs as acceptor bound together through electrostatic interaction, which caused the fluorescence quenching of UCNPs. Upon addition of melamine, AuNPs were...
Here we report a novel label-free fluorescent sensor for ultrasensitive detection of protamine and heparin based on the high quenching ability of gold nanoparticles to the fluorescence of fluorescein. The fluorescence was significantly quenched when fluorescein molecules were attached to the surface of gold nanoparticles by electrostatic interaction. Upon addition of protamine, the fluorescein molecules...
Four new conjugated oligo-phenylene-ethynylenes derivatives, N-methyl-4-(4-acetylthiophenylethynyl)-1,8-naphthalimide (1), thioacetic acid S-[4-(4-aminophenyl-ethynyl)phenyl]ester (2), 4-methylthiophenylethynylbenzenamine (3), N-methyl-4-(4-methyl-thiophenyl-ethynyl)-1,8-naphthalimide (4), were synthesized by Sonogashira and Eglinton cross-coupling reactions. The structures of the four compounds were...
A novel label-free and sensitive fluorescent aptasensor for the detection of potassium ion (K + ) was developed based on the horseradish peroxidase–mimicking DNAzyme (HRP–DNAzyme). In this work, we selected a K + -stabilized single stranded DNA (ssDNA) with G-rich sequence as the recognition element. In the presence of K + , the G-rich DNA folded into the G-quadruplex structure,...
The electrochemical synthesis and characterization of a copolymer, poly(o-toluidine-co-o-aminophenol), were conducted using in situ piezoelectric FTIR spectroelectrochemisty. The monomer feed ratio strongly affects the copolymerization rate and the properties of the copolymer during the electrosynthesis in 0.5M H 2 SO 4 aqueous solution. The effects of scan rate and pH value on the...
Chemical vapor generation (CVG) coupled with non-dispersive atomic fluorescence spectrometry (NDAFS) has been widely used for determination of vapor-forming elements, but most of such works have been focused on single element analysis, and reports dealing with more than three elements simultaneous determination by CVG-NDAFS are rare. In this work, a sensitive and robust analytical procedure for the...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.