"Metal oxide -based heterostructures for gas sensors"- A review.
"Metal oxide -based heterostructures for gas sensors"- A review. Anal Chim Acta. 2018 Dec 18;1039:1-23 Authors: Zappa D, Galstyan V, Kaur N, Munasinghe Arachchige HMM, Sisman O, Comini E Abstract This review focuses on the synthesis and chemical sensing characterization of metal oxide heterostructures reported since 2012. Heterostructures exhibit strong interactions between closely packed interfaces, showing superior performances compared to single structures. Surface effects appear thanks to the magnification of nanostructures' surface leading to an enhancement of surface related properties...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Zappa D, Galstyan V, Kaur N, Munasinghe Arachchige HMM, Sisman O, Comini E Tags: Anal Chim Acta Source Type: research

Lectin-mediated in situ rolling circle amplification on exosomes for probing cancer-related glycan pattern.
Abstract Exosomal surface glycans play important roles in microvesicle protein sorting and exosome-cell interactions, and also provide promising biomarkers for various diseases. However, in situ detection techniques for exosomal glycans are largely lacking. In this work, an exosomal array is fabricated for probing cancer-related exosomal glycan signatures by lectin recognition-mediated in situ rolling circle assembly of fluorophore-labeled DNA. Different from commonly used lectin array, the proposed strategy enables the direct and amplified conversion of glycan recognition signals to fluorescence detection signals...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Feng Y, Guo Y, Li Y, Tao J, Ding L, Wu J, Ju H Tags: Anal Chim Acta Source Type: research

Detection of chloramphenicol using a novel apta-sensing platform based on aptamer terminal-lock in milk samples.
Abstract In this paper, a novel apta-sensing colorimetric platform for rapid detection of chloramphenicol (CAP) in raw milk was developed. The AuNPs are stabilized by short-sequences aptamers against salt induced aggregation and this is the base of most colorimetric aptasensors development. However, the statute shows low sensitivity for the long-sequence aptamers. Herein, we propose an alternative strategy that use intact long-sequence aptamers for develop a highly sensitive AuNP-based colorimetric aptasensor. Determination of CAP in animal derived foods is an urgent demanded in the effort to minimize food safety ...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Javidi M, Housaindokht MR, Verdian A, Razavizadeh BM Tags: Anal Chim Acta Source Type: research

A wide-color-varying ratiometric nanoprobe for detection of norepinephrine in urine samples.
Abstract Owing to its dual role as a hormone and neurotransmitter, norepinephrine (NE) detection is of great significance to biomedical diagnosis. In the present work, we have explored intense green fluorescence of poly (norepinephrine) (PNE) nanoparticles synthesized by oxidizing NE in alkaline condition, in combination with red fluorescent bovine serum albumin-stabilized gold nanoclusters (BSA-AuNCs) for naked-eye detection of NE. The effect of sodium hydroxide on the emission behavior of NE was studied. The surface morphology and optical properties of PNE nanoparticles were characterized by UV-Vis, fluorescence...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Farahmand Nejad MA, Ghasemi F, Hormozi-Nezhad MR Tags: Anal Chim Acta Source Type: research

Potassium-induced ionic conduction through a single nanofluidic pore modified with acyclic polyether derivative.
Abstract Solid-state nanofluidic pores have been attracting considerable attention of scientific community because of their structural and chemical resemblance with biological ion channels for mimicking biological processes in living systems. Compared to ion channels, synthetic nanopores exhibit high stability, control over pore dimensions (size and geometry) and their surface chemical properties can be tuned on demand. Therefore, they are considered perfect candidates to design and develop nanofluidic sensory devices by introducing a variety of functional moieties on the inner pore surface. Here, we present a nan...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Ali M, Ahmed I, Nasir S, Duznovic I, Niemeyer CM, Ensinger W Tags: Anal Chim Acta Source Type: research

Detection and quantification of the toxic marine microalgae Karlodinium veneficum and Karlodinium armiger using recombinase polymerase amplification and enzyme-linked oligonucleotide assay.
van CK, Campàs M Abstract Karlodinium is a dinoflagellate responsible for fish-killing events worldwide. In Alfacs Bay (NW Mediterranean Sea), the presence of two Karlodinium species (K. veneficum and K. armiger) with different toxicities has been reported. This work presents a method that combines recombinase polymerase amplification (RPA) with an enzyme-linked oligonucleotide assay (ELONA) to identify, discriminate and quantify these two species. The system was characterised using synthetic DNA and genomic DNA, and the specificity was confirmed by cross-reactivity experiments. Calibration curves...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Toldrà A, Jauset-Rubio M, Andree KB, Fernández-Tejedor M, Diogène J, Katakis I, O'Sullivan CK, Campàs M Tags: Anal Chim Acta Source Type: research

Ultra-high performance supercritical fluid chromatography in impurity control: Searching for generic screening approach.
In this study, 63 compounds measured as 10 individual mixtures containing in each case an active pharmaceutical ingredient and its relevant impurities, and additional set of 7 basic beta blockers were analyzed using ultra-high performance supercritical fluid chromatography with UV and mass spectrometry detection. The separations were accomplished using 8 different stationary phases (diol, diethylamine, 2-picolylamine, 1-aminoanthracene, BEH 2-ethylpyridine, BEH, CSH pentafluorophenyl, and HSS C18 SB), 6 modifiers (methanol, ethanol, isopropanol, methanol/acetonitrile, methanol/ethanol, ethanol/acetonitrile) and 5 additives...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Plachká K, Švec F, Nováková L Tags: Anal Chim Acta Source Type: research

Flavanols react preferentially with quinones through an electron transfer reaction, stimulating rather than preventing wine browning.
Abstract Wine oxidation changes the chemistry, sensory profile and color of wines. In wine oxidation, phenolics are oxidized to quinones and these reactive compounds can be quenched by sacrificial nucleophiles, such as the A-ring on flavanoids, preventing oxidative damage from the loss of desirable flavor molecules. The "catechol" B-ring on flavanoids, in contrast, can be oxidized by quinones through electron transfer reactions that lead to flavanoid quinones, precursors of browning products. Here we compared the rate of flavanoids reacting by either nucleophilic quinone quenching, or by electron transfe...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Ma L, Waterhouse AL Tags: Anal Chim Acta Source Type: research

Simultaneous observation of concurrent two-dimensional carbon and chlorine/bromine isotope fractionations of halogenated organic compounds on gas chromatography.
This study presents an in-depth investigation of the two-dimensional C and Cl/Br isotope fractionations of HOCs on GC using GC-double focus magnetic-sector high resolution mass spectrometry (GC-DFS-HRMS). The two-dimensional C and Cl/Br isotope fractionations of four organochlorines and four bromobenzenes on GC were simultaneously measured by GC-DFS-HRMS. The isotope fractionations were evaluated with isotope ratios, relative variations of isotope ratios (△hE) and isotope fractionation extents (ΛhE). All the HOCs exhibited significant inverse C and Cl/Br isotope fractionations, with Λ13C of 38.14‰-30...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Tang C, Tan J Tags: Anal Chim Acta Source Type: research

Quantitative assessment of the metabolic products of iron oxide nanoparticles to be used as iron supplements in cell cultures.
, Montes-Bayón M Abstract Iron nanoparticles (NPs) metabolism is directly associated to human health due to their use as anemia treatment and should be studied in detail in cells. Here we present a speciation strategy for the determination of the metabolic products of iron oxide nanoparticles coated by tartaric and adipic acids in enterocytes-like cell models (Caco-2 and HT-29). Such methodology is based on the use of SDS-modified reversed phase high performance liquid chromatography (HPLC) separation using inductively coupled plasma-mass spectrometry (ICP-MS) as Fe selective detector. Post-column isotope d...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Fernández JG, Sánchez-González C, Bettmer J, Llopis J, Jakubowski N, Panne U, Montes-Bayón M Tags: Anal Chim Acta Source Type: research

Multifunctional solid-state electrochemiluminescent chemosensors and aptasensor with free-standing active sites based on task-specific pyrene-terminated polymers via RAFT polymerization.
Abstract Based on the flexible molecular engineering technique of reversible addition-fragmentation chain transfer (RAFT) polymerization, various polymers carrying positive or negative charges and different terminal groups such as pyrene or tertiary amine were synthesized for fabricating multifunctional solid-state electrochemiluminescent (ECL) sensors. Accordingly, the chemosensors immobilizing the ECL probe or co-immobilizing the ECL probe and the coreactant were realized for the quantification of small molecules (e.g., tripropylamine, tetracycline), and an aptasensor was developed for the specific and sensitive...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Xu Y, Chen T, Sun J, Liu J Tags: Anal Chim Acta Source Type: research

A disposable and ultrasensitive ITO based biosensor modified by 6-phosphonohexanoic acid for electrochemical sensing of IL-1 β in human serum and saliva.
In this study, we constructed a new and sensitive ITO based electrochemical immunosensor for detection of interleukin 1β (IL-1β), a cancer biomarker found in serum and saliva. 6-phosphonohexanoic acid (PHA) was used as a biomolecule immobilization matrix for the first time. Anti-IL-1β antibody was utilized as a biorecognition molecule that immobilized onto carboxyl groups of 6-phosphohexanoic acid (PHA) via amide bond. Selective interaction between anti- IL-1β antibodies and IL-1β antigens was investigated by Electrochemical Impedance Spectroscopy (EIS), Cyclic Voltammetry (CV) and Single Frequency...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Aydın EB, Sezgintürk MK Tags: Anal Chim Acta Source Type: research

Silver-filled MWCNT nanocomposite as a sensing element for voltammetric determination of sulfamethoxazole.
Abstract Here, we introduce a new electrode based on Silver-filled multi-walled carbon nanotube (Ag-MWCNT) and methyltrioctyl ammonium chloride (MTOAC) for highly sensitive voltammetric measurement of Sulfamethoxazole (SMX). The electrode showed an electrocatalytic activity as it led to the diminution of the overpotential and an increase in peak current for SMX oxidation in a phosphate buffer solution (pH 6.0). Analysis of surface topography and electrochemical properties of the modified electrode was examined by TEM, EDX and EIS, respectively. Electrochemical performance of the modified electrode was investigated...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Yari A, Shams A Tags: Anal Chim Acta Source Type: research

An available strategy for elemental composition determination of organic impurities in commercial preparations based on accurate mass and peak ratio of isotopic fine structures (IFSs) by dual mode combined-FT-ICR-MS and fraction collection technology.
Abstract A strategy to determine the elemental composition of organic impurities in commercial preparations was established by combining high-performance liquid chromatography (HPLC)-Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and fraction collector with direct infusion-FT-ICR-MS (DI-FT-ICR-MS). Under HPLC-FT-ICR-MS mode, all impurities in model sample were chromatographically separated and collected by fraction collector according to their retention time. The accurate mass of each impurity and their candidate formulae under 1 ppm mass tolerance were calculated. Subsequently, theoreti...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Li X, Chu X, Wang X, Yin R, Zhang X, Zhao Y, Song A, Han F Tags: Anal Chim Acta Source Type: research

High-throughput screening of phthalate-containing objects in the kindergartens by ambient mass spectrometry.
Abstract High-throughput screening of plastic products in children's living environment is necessary to identify phthalate-containing objects for the concern of public health and safety. A novel strategy of probe collecting technique combined with ambient mass spectrometry was developed to carry out the large-scale sample analysis. Analytes from the surface of approximately 500 objects each in two kindergartens in Taiwan were collected using the same number of the metallic probes. After being delivered to laboratory, the analytes on the probes were analyzed with thermal desorption-electrospray ionization/mass spec...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Su H, Huang MZ, Chou JH, Chang TH, Jiang YM, Cho YT, Cheng SC, Wu MT, Shiea J Tags: Anal Chim Acta Source Type: research

A novel fluorimetric sensing strategy for highly sensitive detection of phytic acid and hydrogen peroxide.
Abstract In this paper, we developed a sensitive sensor for phytic acid (PA) and hydrogen peroxide (H2O2) detection based on glutathione-functionalized graphene quantum dots (GQDs@GSH). The fluorescence of GQDs@GSH was found to be effectively quenched by Fe3+ ions via photo-induced electron transfer (PET) process. Upon the addition of PA to GQDs@GSH/Fe3+ system, the fluorescence of GQDs@GSH was significantly restored due to the strong chelating and reducing ability of PA, Fe3+ ions could be reduced to Fe2+ ions by PA and formed PA/Fe2+ complex. Therefore, the "off-on" fluorescence method was constructed ...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Qu Z, Na W, Nie Y, Su X Tags: Anal Chim Acta Source Type: research

Facile preparation of Silicon/ZnO thin film heterostructures and ultrasensitive toxic gas sensing at room temperature: Substrate dependence on specificity.
Abstract Two types of silicon-Zinc oxide (ZnO) heterostructures were prepared simply by depositing (drop casting) chemically prepared ZnO nanoparticles onto single crystalline (p-type) silicon substrates (Si) as well as electrochemically prepared p-type porous silicon (PS). ZnO nanoparticles and PS/ZnO structures were characterized structurally by various techniques. By depositing in-plane gold contacts on the heterostructures, gas sensors were fabricated and characterized electrochemically by dc and ac impedance measurements. The PS/ZnO sensors showed specific response at room temperature for NO2 with increase in...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Betty CA, Sehra K, Barick KC, Choudhury S Tags: Anal Chim Acta Source Type: research

Ultrasensitive fluorescent detection of nucleic acids based on label-free enzymatic-assisted cascade signal amplification.
Abstract A simple and homogenous label-free fluorescent method based on target-triggered and enzymatic-assisted isothermal cascade signal amplification was established for nucleic acid detection. This amplification method consists of two circuits that depend on polymerase and nicking endonuclease. In the presence of a target, a hairpin probe was opened to initiate the polymerization and nicking reaction, producing target analogues and G-rich sequences, and releasing the original target DNA. The released target and produced target analogues then trigger a new amplification cycle. Large amounts of G-rich sequences w...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Qin Y, Liao S, Huang Y, Zhao J, Zhao S Tags: Anal Chim Acta Source Type: research

Magnetic-bioluminescent-nanoliposomes for ultrasensitive and portable detection of protein biomarkers in blood.
In this study, we use alpha-fetoprotein (AFP, a protein biomarker associated with hepatocellular carcinoma) as a model protein. The bioluminescent nanoliposomes conjugated to magnetic particles (LBM) enabled target protein capture, isolation and detection. In this assay, we use a portable magnetic bead separation pen to simplify the steps. The output RLUs (relative light units) had a linear correlation with AFP concentration between 0.05 and 1000 ng/mL, with a limit of detection of 0.016 ng/mL. Our LBM assay for AFP based on the portable luminometer exhibited high specificity for AFP, with no cross-reactivity with othe...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Liu P, Fang X, Cao H, Gu M, Kong J, Deng A Tags: Anal Chim Acta Source Type: research

Opportunities for green microextractions in comprehensive two-dimensional gas chromatography / mass spectrometry-based metabolomics - A review.
Abstract Microextractions have become an attractive class of techniques for metabolomics. The most popular technique is solid-phase microextraction that revolutionized the field of modern sample preparation in the early nineties. Ever since this milestone, microextractions have taken on many principles and formats comprising droplets, fibers, membranes, needles, and blades. Sampling devices may be customized to impart exhaustive or equilibrium-based characteristics to the extraction method. Equilibrium-based approaches may rely on additional methods for calibration, such as diffusion-based or on-fiber kinetic cali...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: de Souza JRB, Dias FFG, Caliman JD, Augusto F, Hantao LW Tags: Anal Chim Acta Source Type: research

A fast and visual method for duplex shrimp pathogens detection with high specificity using rapid PCR and molecular beacon.
Abstract Molecular diagnosis of genome is one of the major methods for pathogens detection. The commonly used PCR method can realize an exponential amplification of the target gene but is time-consuming. In this work, we proposed a duplex and visual method using rapid PCR combined with molecular beacons to specifically detect two kinds of shrimp pathogens in one reaction tube. We only need to observe the fluorescence change of the reaction tube with naked eye to determine the result. A home-made automatic transfer equipment allows reaction tubes shuttling quickly between two water baths to achieve rapid PCR amplif...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Qian C, Wang R, Wu C, Wang L, Ye Z, Wu J, Ji F Tags: Anal Chim Acta Source Type: research

Integrated multichannel all-fiber optofluidic biosensing platform for sensitive and simultaneous detection of trace analytes.
Abstract An integrated multichannel all-fiber optofluidic biosensing platform (M-AOB) has been developed for a sensitive, rapid, and simultaneous detection of up to three trace analytes. The M-AOB platform employs a 1 × 3 fiber optical switch and three single-multimode fiber optic couplers for the transmission of excitation light and fluorescence and one photodiode detector for the simultaneous detection of fluorescence signals of multiple channels based on the time-resolve effect of the fiber optical switch. This design greatly simplified the entire system structure and improved light transmission effic...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Li W, Wang H, Yang R, Song D, Long F, Zhu A Tags: Anal Chim Acta Source Type: research

A facile plasmonic silver needle for fluorescence-enhanced detection of tumor markers.
Abstract Tumor markers have been regularly detected for early cancer diagnosis in clinical oncology. The development of facile and low cost technology has become an important challenge for their diagnosis. We here report a low-cost plasmonic silver needle (PSN) for immunofluorescence detection of tumor biomarkers. The fluorescence signal is enhanced on the needle by up to 220-fold, allowing high-performance detection of tumor markers down to 0.08 ng mL-1. To assess the clinical potential of the proposed assay technique, PSN-based sandwich immunoassay for the detection of alpha-fetoprotein and carcinoembryonic ...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Khan NU, Feng Z, He H, Wang Q, Liu X, Li S, Shi X, Wang X, Ge B, Huang F Tags: Anal Chim Acta Source Type: research

Experimental development of a biosensor system to measure the concentration of phenol diluted in water using alternative sources of oxidoreductase enzymes.
Abstract The presence of phenol in industrial wastewater is an issue of great relevance for petrochemical and energy companies, among others. The high toxicity level of this substance requires polluting industries to continuously monitor the concentration of phenol in their wastewaters so as to comply with environmental regulations and to minimize environmental impact. This research work proposes the experimental development of an analytical method for "in situ" measurement of the concentration of phenol diluted in water, with application in Oil & Gas production wastewater monitoring. The method is b...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Tuta-Navajas G, Gutierrez-Avila K, Roa-Prada S, Chalela-Alvarez G Tags: Anal Chim Acta Source Type: research

Cu-Mn codoped ZnS quantum dots-based ratiometric fluorescent sensor for folic acid.
Abstract In the design of new fluorescent sensors, exploration of new materials with excellent properties and smart designs is of continuing interest. Herein, we designed a dual-emission ratiometric fluorescent sensor by doping ZnS quantum dots (QDs) with Cu2+ and Mn2+ ions. The codoped ZnS QDs with two separated dopant emissions were used as ratiometric fluorescent sensors for folic acid (FA). With addition of FA, the Cu dopant emission was quenched while the Mn dopant emission was enhanced. The fluorescence intensity ratios versus the FA concentrations could be fitted to a linear regression equation ranging from...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Wang Y, Yang M, Ren Y, Fan J Tags: Anal Chim Acta Source Type: research

Highly luminescent green-emitting Au nanocluster-based multiplex lateral flow immunoassay for ultrasensitive detection of clenbuterol and ractopamine.
Abstract A multiplex lateral flow immunoassay sensor based on highly luminescent green-emitting Au nanoclusters (AuNCs-MLFIA sensor) was successfully established for the simultaneous and quantitative determination of clenbuterol (Clen) and ractopamine (RAC) in swine urine. The antigens of Clen and RAC were dispersed on a nitrocellulose membrane as two test lines, and the Au nanoclusters were synthesized from 6-aza-2-thiothymine and l-arginine to obtain highly green luminescence and ultra-small nanoparticles (Arg/ATT/AuNCs). Free carboxyl groups on Arg/ATT/AuNCs enabled conjugation with biomolecules to afford an in...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Peng T, Wang J, Zhao S, Zeng Y, Zheng P, Liang D, Mari GM, Jiang H Tags: Anal Chim Acta Source Type: research

Highly sensitive electrochemical immunosensor for golgi protein 73 based on proximity ligation assay and enzyme-powered recycling amplification.
In this study, a highly sensitive electrochemical immunosensor which combines the highly selective proximity ligation assay (PLA) and highly efficient enzyme-powered recycling amplification has been developed for GP73 determination. PLA is triggered by affinity binding of two labelled antibody-DNA (P1-RAb and P2-MAb) to target protein, resulting in increased specificity. The formed immunocomplex hybrids with DNA2 to realize the release of methylene blue labelled mononucleotides fragment with the help of exonuclease III, which acts as the power of recycling amplification. The fragment can diffuse easily to the nafion modifi...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Zhang Y, Huang X, Luo F, Lei Y, Chen L, Weng Z, Guo L, Lin Z Tags: Anal Chim Acta Source Type: research

Detection of nitrite with a surface-enhanced Raman scattering sensor based on silver nanopyramid array.
Abstract Nutrient pollution is of worldwide environmental and health concerns due to extensive use of nitrogen fertilizers and release of livestock waste, which induces nitrite compounds in aquatic systems. Herein a surface-enhanced Raman scattering (SERS) sensor is developed for nitrite detection based on coupling between the plasmonic gold nanostars and the silver nanopyramid array. When nitrite is present in the assay, an azo group is formed between the 1-naphthylamine-functionalized silver nanopyramids and the 4-aminothiophenol-functionalized gold nanostars. This not only generates the SERS spectral fingerprin...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Zheng P, Kasani S, Shi X, Boryczka AE, Yang F, Tang H, Li M, Zheng W, Elswick DE, Wu N Tags: Anal Chim Acta Source Type: research

Label-free cytosensing of cancer cells based on the interaction between protein and an electron-transfer carbohydrate-mimetic peptide.
Abstract We used an electron-transfer carbohydrate-mimetic peptide (YYYYC) to construct an electrochemical cytosensing system. Magnetic beads were modified with either asialofetuin (ASF) or soybean agglutinin (SBA) to evaluate the effect on cell sensing. Because SBA binds to the galactose residue that exists at the terminals of the carbohydrate chains in ASF, the target protein was accumulated on the protein magnetic beads. SBA is an example of N-acetylgalactosamine- and galactose-binding proteins that readily combine with YYYYC. When the peptides and protein-immobilized beads competed for a target protein, the pe...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Sugawara K, Kuramitz H, Kadoya T Tags: Anal Chim Acta Source Type: research

Colorimetric sensor for the detection of H2S and its application in molecular half-subtractor.
Abstract Azine based new colorimetric sensor 1 for the detection of gasotransmitter H2S has been reported. Sensor 1 used to detect the H2S with a remarkable red shift of 105 nm in the absorption spectra with a colour change from light yellow to brown red. Importantly, rare example of azine derivative has been used as a colorimetric probe for H2S detection using deprotonation mechanism. H2S induced deprotonation of one of the -OH proton followed by a change in resonance of 1 is responsible for the ratiometric spectral and colour change. The detection response was quick and the LOD calculated as 18.2 μM. Sens...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Kaushik R, Ghosh A, Singh A, Jose DA Tags: Anal Chim Acta Source Type: research

Ultrasensitive detection of glutathione based on liquid crystals in the presence of γ-glutamyl transpeptidase.
In this study, we proposed a novel strategy for sensitive and selective detection of GSH based on LC sensing platform coupled with its inhibition of γ-GT. The γ-GT cleavable surfactant, dodecyl N-ethanamide N, N, N-trimethylammonium bromide (DAA), was synthesized and utilized to decorate the aqueous/LC interface. A black optical image of LCs was observed due to formation of the self-assembled DAA monolayer at the interface. Subsequently, the optical response of LCs returned to bright appearance after transferring γ-GT to the DAA-laden interface because DAA could be enzymatically hydrolyzed by γ-GT a...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Zhou L, Kang Q, Hu O, Yu L Tags: Anal Chim Acta Source Type: research

Application of chemometric methods to XRF-data - A tutorial review.
Abstract X-ray fluorescence (XRF) spectrometry is a modern method of element analysis, widely applied in forensic science, archeology, geochemistry and other fields. Chemometric data processing tools and approaches may help XRF to become even more informative. These tools allow for convenient data visualization, exploration of hidden relations in the data, classification of samples and quantitative treatment of noisy and overlapped spectra. This review describes the most popular chemometric techniques employed in XRF studies and provides typical examples of such applications. PMID: 30327110 [PubMed] (Source: ...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Panchuk V, Yaroshenko I, Legin A, Semenov V, Kirsanov D Tags: Anal Chim Acta Source Type: research

Hollow-fiber renewal liquid membrane extraction coupled with 96-well plate system as innovative high-throughput configuration for  the determination of endocrine disrupting compounds by high-performance liquid chromatography-fluorescence and diode array detection.
Hollow-fiber renewal liquid membrane extraction coupled with 96-well plate system as innovative high-throughput configuration for the determination of endocrine disrupting compounds by high-performance liquid chromatography-fluorescence and diode array detection. Anal Chim Acta. 2018 Dec 21;1040:33-40 Authors: Lopes D, Dias AN, Merib J, Carasek E Abstract This paper describes a new configuration of the hollow fiber renewal liquid membrane (HFRLM) procedure for the high-throughput determination of the endocrine disrupting compounds 4-nonylphenol, 4-octylphenol, 4-tert-octylphenol, methylparaben, e...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Lopes D, Dias AN, Merib J, Carasek E Tags: Anal Chim Acta Source Type: research

Mixed Vapor Generation Device for delivery of homemade explosives vapor plumes.
Abstract While there is a large body of research on the properties and detection of traditional military high explosives and propellant low explosives, there is a dearth of research on homemade explosive (HME) materials, though they are prevalent today. The safety of working with these materials in the laboratory is the greatest limiting factor preventing HME research. A vapor delivery tool, the Mixed Vapor Generation Device (MV-Gen), was designed to safely contain the individual solid or liquid components that often compose homemade explosives vapor plumes and deliver the mixed component vapors for instrumental s...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: DeGreeff LE, Katilie CJ, Malito M, Giordano B Tags: Anal Chim Acta Source Type: research

Optimization and validation of a fast digestion method for the determination of major and trace elements in breast milk by ICP-MS.
Abstract Breast milk guarantees all the nutrients required by infants during their first few months of life and remains the most important food source for their health and growth. However, the mother may transfer potentially toxic chemicals to the suckling infant through breastfeeding. The aim of this study was to optimize and validate a fast method for the determination of a total content of 34 elements (Al, As, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, Sb, Se, Si, Sn, Sr, Te, Ti, Tl, U, V, and Zn) in liquid and lyophilized breast milk. The samples were subjected to HNO3:H2O...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Astolfi ML, Marconi E, Protano C, Vitali M, Schiavi E, Mastromarino P, Canepari S Tags: Anal Chim Acta Source Type: research

One-step DNA purification and amplification on an integrated plastic microdevice for on-site identification of foodborne pathogens.
This study is expected to pave the way for developing an integrated monolithic thermoplastic microdevice suitable for rapidly identifying foodborne pathogens with reduced operation, decreased manufacturing cost, and enhanced device disposability. PMID: 30327114 [PubMed - in process] (Source: Analytica Chimica Acta)
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Trinh KTL, Zhang Y, Lee NY Tags: Anal Chim Acta Source Type: research

A cotton thread fluidic device with a wall-jet pencil-drawn paper based dual electrode detector.
Abstract A simple and sensitive device is presented based on the use of pencil-drawn paper based electrochemical detector placed at the end of a cotton thread fluidic channel in wall-jet configuration. This innovative and fast responding electroanalytical system can be adopted for both single and dual electrode electrochemical detection, this last achieved by applying two different potentials at two independent working electrodes drawn on the opposite faces of the paper based detector. Its performance was preliminarily optimized by adopting hexacyanoferrate(II) as probe species undergoing reversible electrochemica...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Dossi N, Toniolo R, Terzi F, Sdrigotti N, Tubaro F, Bontempelli G Tags: Anal Chim Acta Source Type: research

Development of a self-priming PDMS/paper hybrid microfluidic chip using mixed-dye-loaded loop-mediated isothermal amplification assay for multiplex foodborne pathogens detection.
Abstract Foodborne pathogen is the primary cause of foodborne disease outbreak. Given its great damage, a sensitive, simple and rapid detection method is demanded. Herein, we described a self-priming polydimethylsiloxane (PDMS)/paper hybrid microfluidic chip, termed SPH chip, with mixed-dye-loaded loop-mediated isothermal amplification (LAMP) for multiplex foodborne pathogens detection. Staphylococcus aureus (SA) and Vibrio parahaemolyticus (VP) were chosen to verify the novel method. Compared to other similar detection devices, the SPH chip required easier fabrication process, less operation steps and lower cost....
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Pang B, Fu K, Liu Y, Ding X, Hu J, Wu W, Xu K, Song X, Wang J, Mu Y, Zhao C, Li J Tags: Anal Chim Acta Source Type: research

Surface plasmon resonance biosensor for the accurate and sensitive quantification of O-GlcNAc based on cleavage by β-D-N-acetylglucosaminidase.
In this study, an accurate and sensitive surface plasmon resonance (SPR) biosensor for O-GlcNAc detection that is based on β-D-N-acetylglucosaminidase (OGA) and Au nanoparticles (AuNPs) was developed. In this strategy, AuNPs were used to amplify the SPR signal and improve the biosensor's sensitivity; OGA was used to cleave O-GlcNAc from O-GlcNAcylated biomolecules. The interaction between AuNPs labeled wheat germ agglutinin (AuNPs/WGA) and O-GlcNAcylated biomolecules on a modified Au film treated with and without OGA was recorded by SPR. The change of the SPR signal moves linearly with the amount of O-GlcNAc on the Au...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Gao L, Zhao R, Wang Y, Lu M, Yang D, Fa M, Yao X Tags: Anal Chim Acta Source Type: research

Imprinted proteins as a receptor for detection of zearalenone.
Abstract A strategy to design an immunoassay based on imprinted proteins to detect a foodborne toxin zearalenone (ZEN) has been proposed. Proteins were used as scaffolds for generation of binding cavities with a high specificity against ZEN. Different proteins and different bioimprinting approaches were tested. The imprinted proteins primarily prepared in a tube and then immobilized on a microwell plate, and directly prepared in the microwell plate were compared for an application in immunosorbent detection of ZEN in naturally contaminated wheat and maize samples. The assay was combined with a rapid extraction tec...
Source: Analytica Chimica Acta - October 18, 2018 Category: Chemistry Authors: Pidenko P, Zhang H, Lenain P, Goryacheva I, De Saeger S, Beloglazova N Tags: Anal Chim Acta Source Type: research

Natural deep eutectic solvents-mediated extractions: The way forward for sustainable analytical developments.
V, Silva MF Abstract The concept of sustainable development has impacted in analytical chemistry changing the way of thinking processes and methods. It is important for analytical chemists to consider how sample preparation can integrate the basic concepts of Green Chemistry. In this sense, the replacement of traditional organic solvents is of utmost importance. Natural Deep Eutectic Solvents (NADES) have come to light as a green alternative. In the last few years, a growing number of contributions have applied these natural solvents proving their efficiency in terms of extraction ability, analyte stabilization ca...
Source: Analytica Chimica Acta - October 4, 2018 Category: Chemistry Authors: Fernández MLÁ, Boiteux J, Espino M, Gomez FJV, Silva MF Tags: Anal Chim Acta Source Type: research

Sensitive DNA detection by polymerase chain reaction with gold nanoparticles.
Abstract We developed a novel strategy for rapid colorimetric detection of specific DNA sequence based on gold nanoparticles assemblies induced by polymerase chain reaction (PCR) product. In the presence of target DNA, the two DNA-functionalized AuNP probes selectively hybridized with the prohibited nucleic acid segments of two primers owing to the zipping off of the hairpin structures during PCR process, resulted in the aggregation of AuNPs with a concomitant color change from red to blue-purple. It is a convenient and universal method for sensitive DNA detection with no need for any further post-treatment of the...
Source: Analytica Chimica Acta - October 4, 2018 Category: Chemistry Authors: Zou L, Shen R, Ling L, Li G Tags: Anal Chim Acta Source Type: research

A novel enzyme-free glucose and H2O2 sensor based on 3D graphene aerogels decorated with Ni3N nanoparticles.
Abstract In this work, a novel enzyme-free glucose and hydrogen peroxide (H2O2) sensor based on Ni3N nanoparticles on conductive 3D graphene aerogels (Ni3N/GA) has been successfully synthesized by using hydrothermal reaction, freeze-dried and then calcined under NH3 atmosphere. The obtained Ni3N/GA composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption-desorption isotherms and electrochemical methods. The results show the obtained 3D Ni3N/GA composites exhibit excellent electro...
Source: Analytica Chimica Acta - October 4, 2018 Category: Chemistry Authors: Yin D, Bo X, Liu J, Guo L Tags: Anal Chim Acta Source Type: research

Dual-mode fluorescent and colorimetric immunoassay for the ultrasensitive detection of alpha-fetoprotein in serum samples.
We present a novel dual-mode fluorescent and colorimetric immunosensor based on conventional immunoassay platforms by utilizing a gold nanoflower (AuNF)-loaded fluorescein molecule (AuNF@Fluorescein) as signal output. The AuNFs were modified with thiolated carboxyl ligand, which consisted of a hydrophobic alkane chain as hydrophobic wallet for fluorescein encapsulation, a tetra (ethylene glycol) unit for biocompatibility and solubility, and a functional carboxyl group for the conjugation of biorecognition molecules for biosensing. The resultant AuNFs showed a high loading capacity of 3.74 × 106 fluorescein molecu...
Source: Analytica Chimica Acta - October 4, 2018 Category: Chemistry Authors: Zhou Y, Huang X, Xiong S, Li X, Zhan S, Zeng L, Xiong Y Tags: Anal Chim Acta Source Type: research

A simple and sensitive fluorescence method for detection of telomerase activity using fusion protein bouquets.
Abstract Telomerase is considered as a widely accepted cancer biomarker for early cancer diagnostics. Herein, we develop a simple, ultrahigh sensitivity method for detection of telomerase activity, which relied on that RecA-GFP fusion proteins wrapped around telomeric DNA to form fluorescence bouquets. RecA-GFP fusion protein was synthesized through fusion protein technology. In the presence of telomerase, telomerase elongation products are wrapped around by RecA-GFP fusion protein to form big fluorescent bouquets, which resulted in strong fluorescence. This method has the linear range from 50 to 1000 HeLa cells a...
Source: Analytica Chimica Acta - October 4, 2018 Category: Chemistry Authors: Wu T, Zhang Y, Hou T, Zhang Y, Wang S Tags: Anal Chim Acta Source Type: research

Aptamer proximity recognition-dependent strand translocation for enzyme-free and amplified fluorescent detection of thrombin via catalytic hairpin assembly.
Abstract By coupling a new aptamer proximity recognition-dependent strand translocation strategy with catalytic hairpin assembly (CHA) signal amplification, we have developed a simple and sensitive method for detecting thrombin in human serums. Simultaneous binding of two engineered aptamer probes to the thrombin target significantly increases the local concentrations of the two probes and facilitates the translocation of a ssDNA strand from one of the probes to the other through toehold mediated strand displacement. Such a strand translocation leads to the generation of a ssDNA tail in the aptamer sequence for su...
Source: Analytica Chimica Acta - October 4, 2018 Category: Chemistry Authors: Li J, Zhou W, Yuan R, Xiang Y Tags: Anal Chim Acta Source Type: research

Fabricating carbon-nanotubes-based porous foam for superoxide electrochemical sensing through one-step hydrothermal process induced by phytic acid.
Abstract The detection of superoxide anions (O2•-) is widely considered as a potential way for cancer diagnosis and the development of enzyme-mimic catalysts is the main challenge in the establishment of electrochemical sensors for O2•- sensing in real samples. Here we present a novel enzyme- and metal-free electrochemical catalyst for superoxide (O2•-) sensing based on the widely-used carbon nanotubes (CNT). Through a one-step hydrothermal process induced by phytic acid (PA), CNT-based porous foam (PACNTF) was successfully obtained. Characterizations demonstrated the enhanced defect and disorder de...
Source: Analytica Chimica Acta - October 4, 2018 Category: Chemistry Authors: Cai X, Chen K, Wang Z, Sun W, Zhao H, Zhang H, Chen H, Lan M Tags: Anal Chim Acta Source Type: research

Hairpin-structured probe conjugated nano-graphene oxide for the cellular detection of connective tissue growth factor mRNA.
This report introduces a fluorescent probe that targets a potential abnormal scar biomarker (connective tissue growth factor (CTGF) mRNA) in skin fibroblasts. This probe is constructed of hairpin-structured probes (HPs) targeting CTGF mRNA and the nano-graphene oxide (nano-GO) base. The HPs are non-covalently absorbed on the surface of nano-GO, which pre-quenches the fluorescence of HPs. Close proximity of complementary CTGF mRNA would lead to preferential HP hybridization and dissociation from nano-GO, which restores the fluorescence signal from HPs. Utilizing this probe, we can distinguish abnormal fibroblasts derived fr...
Source: Analytica Chimica Acta - October 4, 2018 Category: Chemistry Authors: Wang M, Wiraja C, Wee M, Yeo D, Hu L, Xu C Tags: Anal Chim Acta Source Type: research

Fluorescent/SERS dual-sensing and imaging of intracellular Zn2.
Abstract A fluorescent and surface-enhanced Raman spectroscopy (SERS) dual-mode probe is developed for imaging of intracellular Zn2+ based on N-(2-(bis(pyridine-2-ylmethyl)amino)ethyl)-2-mercaptoacetamide (MDPA) modified gold nanoparticles (MDPA-GNPs). Benefiting from the chelation-enhanced fluorescence (CHEF) between MDPA-GNPs and Zn2+, the fluorescent intensities of MDPA-GNPs are substantially enhanced with the increment of Zn2+ concentrations, which can be clearly observed by the naked eye. Under physiological conditions, the probe exhibits a stable response for Zn2+ from 1 μM to 120 μM, with a detect...
Source: Analytica Chimica Acta - October 4, 2018 Category: Chemistry Authors: Li D, Ma Y, Duan H, Jiang F, Deng W, Ren X Tags: Anal Chim Acta Source Type: research

Fluorescence enhancement of silver nanocluster at intrastrand of a 12C-loop in presence of methylated region of sept 9 promoter.
Abstract Determining methylation state of a particular DNA sequence is an essential task in many epigenetic investigations. Here a facile method based on silver nanocluster (AgNCs) fluorescence enhancement is presented. Target sequences were selected from Sept9 promoter region that its hypermethylation is demonstrated as a reliable biomarker of colorectal cancer. Probe DNA was complementary to a 25 nucleotide of the target region and possessed twelve additional cytosines in the middle to grant the formation of AgNCs. After probe strands were hybridized with methylated and non-methylated targets separately, AgNCs w...
Source: Analytica Chimica Acta - October 4, 2018 Category: Chemistry Authors: Sadeghan AA, Soltaninejad H, Hosseinkhani S, Hosseini M, Ganjali MR, Asadollahi MA Tags: Anal Chim Acta Source Type: research