Recent advances in aflatoxin B1 detection based on nanotechnology and nanomaterials-A review.
Abstract Aflatoxin B1(AFB1) is one of the most toxic mycotoxins produced by fungi and results in inevitable contamination of food and feed at very low concentrations. Therefore, there is an urgent need to implement selective, sensitive and highly convenient methods for the determination of aflatoxin B1. Among these methods, the progress of nanomaterials, owing to their high performances and versatile properties, offers great prospects for realizing highly sensitive, selective and simple detection of AFB1, overcoming the restrictions of traditional methods such as process-complicated, time-consuming, labor-intensiv...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Xue Z, Zhang Y, Yu W, Zhang J, Wang J, Wan F, Kim Y, Liu Y, Kou X Tags: Anal Chim Acta Source Type: research

Self-heated Ag-decorated SnO2 nanowires with low power consumption used as a predictive virtual multisensor for H2S-selective sensing.
Abstract Multisensor systems with low-power consumption are emerging for the Internet of Things. In this work, we demonstrate the use of self-heated networked Ag-decorated SnO2 NW sensors integrated into a portable module for selective detection of H2S gas at low power consumption, and the integrated system is simulated as a virtual multisensor under varying heating powers for identifying and quantifying different reducing gases. The H2S gas-sensing characterisations at the different self-heating powers of 2-10 mW showed that the gas response significantly increased with the increase in Ag density decoration and...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Ngoc TM, Van Duy N, Hung CM, Hoa ND, Nguyen H, Tonezzer M, Van Hieu N Tags: Anal Chim Acta Source Type: research

Sensitive amperometric immunosensor with improved electrocatalytic Au@Pd urchin-shaped nanostructures for human epididymis specific protein 4 antigen detection.
Abstract Sensitive detection of early ovarian cancer is imminent for women's health. Human epididymis specific protein 4 antigen (HE4 Ag), as a novel tumor marker, has good specificity and sensitivity in ovarian cancer markers, especially for the detection of early ovarian cancer. In this work, a novel and ultrasensitive sandwich-type amperometric electrochemical immunosensor was constructed using amine modified graphene supported gold nanorods (Au NRs/NH2-GS) as a sensor platform and core-shell Au@Pd urchin-shaped nanostructures (Au@Pd USs) as a label of the secondary antibodies (Ab2, Au@Pd USs-Ab2) to realize th...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Yan Q, Cao L, Dong H, Tan Z, Liu Q, Zhang W, Zhao P, Li Y, Liu Y, Dong Y Tags: Anal Chim Acta Source Type: research

New approach for mapping and physiological test of silica nanoparticles accumulated in sweet basil (Ocimum basilicum) by LA-ICP-MS.
Abstract Behavior of silica nanoparticles (SiNPs) in sweet basil was studied using laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS) as an in situ monitoring tool. Although the use of SiNP for environmental applications is interesting, detailed studies in plants for distributional mapping and quantitative determination have been difficult because the detection of 28Si+ suffers from severe molecular interference and high background in ICP-MS. In this work, yttrium/fluorescein-isothiocyanate-doped silica nanoparticles (Y/FITC-doped SiNPs) synthesized in our lab were used to substitute for undop...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Ko JA, Furuta N, Lim HB Tags: Anal Chim Acta Source Type: research

Scanning electrochemical microscopy with conducting polymer probes: Validation and applications.
ez-López J Abstract Scanning electrochemical microscopy (SECM) allows spatially and temporally resolved measurements of a broad range of reactive surfaces and specimens, typically using electrochemically active metal probes. While conducting polymers (CPs) present several analytical properties of interest due to their chemical versatility, potentially enabling the measurement of ionic fluxes as well as redox processes, they have not been widely used as probe materials for SECM. CPs can be modified and fine-tuned to improve experimental parameters and they can be easily prepared by electrodeposition. In this...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Claudio-Cintrón MA, Rodríguez-López J Tags: Anal Chim Acta Source Type: research

An ultrasensitive electrochemical detection of tryptase using 3D macroporous reduced graphene oxide nanocomposites by one-pot electrochemical synthesis.
In this study, we introduce an ultrasensitive and stable sensing platform based on gold nanoparticle decorated 3D reduced graphene oxide - carbon nanotube nanocomposites (GNP/CNT/rGO) for detection of tryptase (Tryp), which is a potential biomarker within nasal secretions for allergic rhinitis (AR). The GNP/CNT/rGO on the glassy carbon electrode (GCE) was fabricated through single-step one-pot electrochemical co-reduction and deposition. The GNP/CNT/rGO exhibited excellent electrocatalytic activity as the working electrode compared with bare GCE, GNP/rGO and CNT/rGO on GCEs. The enhanced performance of GNP/CNT/rGO may be a...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Lee J, Lee YJ, Eun YG, Lee GJ Tags: Anal Chim Acta Source Type: research

A green and simple sample preparation method to determine pesticides in rice using a combination of SPME and rotating disk sorption devices.
In this study, a novel environmentally-friendly approach was developed to overcome certain limitations in the analysis of solid food samples. An experimental setup based on solid-phase microextraction apparatus coupled to a rotating disk device is proposed for the determination of polar and slightly-polar pesticides including carbofuran, molinate, atrazine, simazine and tebuconazole in rice samples. In this innovative procedure, a rice sample is inserted into the cavity of the rotating disk device which is then immersed in an aqueous solution followed by high-speed agitation. In this case, water is employed as a green solv...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Omena E, Oenning AL, Merib J, Richter P, Rosero-Moreano M, Carasek E Tags: Anal Chim Acta Source Type: research

Rapid screening of formaldehyde in food using paper-based titration.
Abstract A simple paper-based analytical device (PAD) has been developed to rapidly detect formaldehyde (FA) in food samples. The analysis was based on sulfite assay where FA reacted with excess sulfite to generate sodium hydroxide (NaOH) that was quantified on PAD using acid-base titration. The PAD consisted of a central sample zone connected to ten reaction and detection zones. All detection zones were pre-deposited with polyethylene glycol (PEG) with phenolphthalein (Phph) as an indicator. Reaction zones contained different amounts of the titrant, potassium hydrogen phthalate (KHP). On flowing into reaction zon...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Taprab N, Sameenoi Y Tags: Anal Chim Acta Source Type: research

An amplification strategy using DNA-Peptide dendrimer probe and mass spectrometry for sensitive MicroRNA detection in breast cancer.
In this study, we circumvented copying of nucleic acid sequence and developed a signal amplification strategy based on a novel DNA-peptide dendrimer (DPD) probe coupled with mass spectrometry. The DPD probe RP8-MAP4-DNA contained three functional domains, including substrate peptides containing eight reporter peptides and tryptic cleavage sites, peptide dendrimer scaffold and DNA complementary to target miRNA. The probe was first hybridized with the target miRNA (i.e., miR-21) that was biotinylated and attached to streptavidin agarose in advance. After trypsin digestion, the reporter peptide was liberated and quantified us...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Liu L, Kuang Y, Yang H, Chen Y Tags: Anal Chim Acta Source Type: research

Determination of nerve agent metabolites in human urine by femtosecond laser ionization mass spectrometry using 2-(bromomethyl)naphthalene as a derivatizing reagent.
Abstract Nerve agent metabolites (NAMs) derived from alkyl methyl phosphonic acids, such as ethyl methylphosphonic acid (EMPA), isopropyl methylphosphonic acid (IMPA), and pinacolyl methylphosphonic acid (PMPA), were extracted from human urine using diethyl ether as an extractant. After exchanging the diethyl ether solvent to acetonitrile, the analytes were derivatized with 2-(bromomethyl)naphthalene (BMN). The reaction products of the BMN and NAMs, i.e., MN-EMPA, MN-IMPA, and MN-PMPA, were separated by gas chromatography (GC) and measured by mass spectrometry (MS) using a femtosecond laser emitting at 267 nm as...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Son VV, Nakamura H, Imasaka T, Imasaka T Tags: Anal Chim Acta Source Type: research

Advanced liquid chromatography-mass spectrometry enables merging widely targeted metabolomics and proteomics.
Abstract Either widely targeted metabolomics or quantitative proteomics usually requires unique analytical platform. However, cross-platform omics studies entail higher levels of complexity and uncertainty, and result in a significant obstacle for high throughput assay as well. It is thereby urgent to pursue an integrative approach being capable of merging these two omics terms, namely widely targeted bi-omics. As an eligible analytical tool for large-scale targeted metabolomics, reversed phase liquid chromatography-hydrophilic interaction liquid chromatography-tailored selected reaction monitoring (RPLC-HILIC-tai...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: Liu W, Song Q, Cao Y, Zhao Y, Huo H, Wang Y, Song Y, Li J, Tu P Tags: Anal Chim Acta Source Type: research

Hg-supported phospholipid monolayer as rapid screening device for low molecular weight narcotic compounds in water.
This study positions the fabricated Pt/Hg-supported phospholipid sensor element in the context of more conventional biomembrane-based screening platforms. The technology has been used together with immobilised artificial membrane (IAM) chromatography and COSMOmic simulation methods to screen the interaction of a series of low molecular weight narcotic organic compounds in water with phosphatidylcholine (PC) membranes. For these chemicals it is shown that toxicity to aquatic species is related to compound hydrophobicity which is associated with compound accumulation in the phospholipid membrane as modelled by IAM chromatogr...
Source: Analytica Chimica Acta - May 17, 2019 Category: Chemistry Authors: William N, Nelson A, Gutsell S, Hodges G, Rabone J, Teixeira A Tags: Anal Chim Acta Source Type: research

Sequence-specific preconcentration of a mutation prone KRAS fragment from plasma using ion-tagged oligonucleotides coupled to qPCR compatible magnetic ionic liquid solvents.
In this study, a series of ion-tagged oligonucleotides (ITO) were synthesized using thiol-ene click chemistry and designed to selectively anneal target DNA. The ITO-DNA duplex was subsequently captured using a hydrophobic magnetic ionic liquid (MIL) as a liquid support. Extracted target DNA was quantified by adding the DNA-enriched MIL to the quantitative polymerase chain reaction (qPCR) buffer to streamline the extraction procedure. Clinically relevant concentrations of the mutation prone KRAS fragment, which has been linked to colorectal, lung, and bladder cancer, were preconcentrated using the ITO-MIL strategy allowing ...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Emaus MN, Varona M, Anderson JL Tags: Anal Chim Acta Source Type: research

A dynamic, ultra-sensitive and "turn-on" strategy for fluorescent detection of uranyl based on DNAzyme and entropy-driven amplification initiated circular cleavage amplification.
A dynamic, ultra-sensitive and "turn-on" strategy for fluorescent detection of uranyl based on DNAzyme and entropy-driven amplification initiated circular cleavage amplification. Anal Chim Acta. 2019 Aug 30;1068:104-110 Authors: Yun W, Wu H, Yang Z, Wang R, Wang C, Yang L, Tang Y Abstract A uranyl detection strategy with ultra-sensitivity was developed based on entropy-driven amplification and DNAzyme circular cleavage amplification. The cleavage of UO22+-specific DNAzyme produces a DNA fragment to initiate the entropy-driven amplification. Two DNA sequences released from the entropy-driven ...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Yun W, Wu H, Yang Z, Wang R, Wang C, Yang L, Tang Y Tags: Anal Chim Acta Source Type: research

A freestanding all-solid-state polymeric membrane Cu2+-selective electrode based on three-dimensional graphene sponge.
Abstract A novel freestanding all-solid-state polymeric membrane Cu2+-selective electrode (Cu2+-ISE) is proposed based on three-dimensional graphene sponge (3D GS). The 3D GS electrode has been characterized by cyclic voltammetry, electrochemical impedance spectroscopy, and contact angle measurements. Experiments show that 3D GS possesses a large electrical double layer capacitance, good conductivity, and high hydrophobicity. Based on these superior properties, 3D GS has been applied as both electrode substrate and solid contact for construction of a freestanding all-solid-state polymeric membrane Cu2+-ISE. The 3D...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Li J, Qin W Tags: Anal Chim Acta Source Type: research

A new chromatographic approach to analyze methylproteome with enhanced lysine methylation identification performance.
In this study, we presented a novel chromatography-based enrichment method for global methylproteome analysis. The offline multidimensional tandem chromatography combining strong cation exchange (SCX) chromatography, immobilized metal ion affinity chromatography (IMAC) and high-pH reversed-phase chromatography (high-pH RP) was applied in the large-scale analysis of methylproteome. Totally, 860 forms on 765 sites were identified from BEL cells, covering all five arginine/lysine methylation forms. Among them, 27.21% were lysine methylation forms. This technique allows the simultaneous analysis of both arginine and lysine met...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Wang Q, Liu Z, Wang K, Wang Y, Ye M Tags: Anal Chim Acta Source Type: research

Modular and conservative procedure for the quantification of amino functionalities bonded to solid porous matrices.
In this study an original and operationally simple procedure designed to quantify the density of basic groups (typically amino groups) chemically bonded to the surface of porous solids, which also allows a full recovery of the analysed material, is presented. The method is based on the preventive acid-base reaction of the basic groups linked to the solid by 3,5-dinitrobenzoic acid (DNBA). The quantification of the basic functionalities is then performed by an UV-spectrophotometric retro-titration of the thus salified solid matrix (or, alternatively, by HPLC approach), resorting to a preventive either acid or basic displace...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Manzi G, Buonsenso F, Ismail OH, Ciogli A, Siani G, Pierini M Tags: Anal Chim Acta Source Type: research

Water-soluble pillar[6]arene functionalized PdPt porous core-shell octahedral nanodendrites to construct highly sensitive and robust neuron-specific enolase immunosensor by host-guest chemistry assisted catalytic amplification.
Abstract In this work, water-soluble pillar[6]arene functionalized PdPt porous core-shell octahedral nanodendrites (WP6@PdPt PCONs) were simply synthesized and used for the fabrication of NSE immunosensor. The newest generation of macrocyclic host and biomimetic nano-enzymes have been effectively integrated to achieve the robust immobilization of signal molecules by host-guest molecular recognition and sensitively catalytic amplification of electrochemical signals. The addition of Pd and the formation of WP6@PdPt PCONs unique bimetallic nanostructure are beneficial to changing Pt-based catalyst electronic structur...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Zhou X, Qian X, Tan X, Ran X, Li Z, Huang Z, Yang L, Xie X Tags: Anal Chim Acta Source Type: research

Design and fabrication of a two-phase diamond nanoparticle aided fast PCR device.
Abstract Polymerase Chain Reaction (PCR) is an important and prevalent technique in biotechnology because of its crucial role in cloning DNA fragments and diagnostic applications. In the present study, a high-throughput two-phase PCR device is designed and fabricated which utilizes a serpentine microchannel together with a spiral structure. The former is for the droplet-generation and mixing and the latter is for the thermal cycling process. Moreover, the effect of diamond nanoparticles (diamondNP) on the performance of PCR is also investigated while using commercial PCR devices and the fabricated PCR device desig...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Madadelahi M, Ghazimirsaeed E, Shamloo A Tags: Anal Chim Acta Source Type: research

Isolation and identification of Listeria monocytogenes utilizing DC insulator-based dielectrophoresis.
Abstract Foodborne pathogens pose one of the greatest challenges facing public health in the modern day. One important pathogen, Listeria monocytogenes, is known to be challenging to detect and identify. Three serovars cause most of the Listeria related food-borne illnesses, which the Centers for Disease Control currently utilizes a combination of pulsed-field gel electrophoresis and whole genome sequencing for identification and the determination of clusters and outbreaks. There is a potential method for rapid collection of epidemiological information by exploiting the electrokinetic and dielectrophoretic propert...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Crowther CV, Hilton SH, Kemp L, Hayes MA Tags: Anal Chim Acta Source Type: research

Near-infrared carbon dots-based fluorescence turn on aptasensor for determination of carcinoembryonic antigen in pleural effusion.
Abstract Early detection of carcinoembryonic antigen (CEA) is of great significance for the screening, diagnosis, monitoring and prognosis analysis of lung cancer. Herein, a novel fluorescence aptasensor with high signal-noise ratio (SNR) was constructed to achieve highly-sensitive detection of CEA relied upon the fluorescence resonance energy transfer (FRET) between near-infrared carbon dots (NIR-CDs) and gold nanorods (AuNRs). Initially, AuNRs@SiO2-Aptamer and NIR-CDs-DNA probe were prepared via the covalent bonding reaction between their corresponding carboxyl and amino groups, respectively. After DNA hybridiza...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Shao K, Wang L, Wen Y, Wang T, Teng Y, Shen Z, Pan Z Tags: Anal Chim Acta Source Type: research

Fluorescent hydrogen sulfide probes based on azonia-cyanine dyes and their imaging applications in organelles.
Abstract Three hydrogen sulfide (H2S) probes based on an azonia-cyanine skeleton were successfully designed and prepared. Probe 1a, containing 4-chloro-7-nitro-1,2,3-benzoxadiazole connected to the cyanine dye, had an emission at 660 nm that was enhanced 4.5-fold by the reduced photoinduced electron transfer process when reacting with H2S. Probes 1b and 1c were constructed from cyanine dyes with electron withdrawing 2,4-dinitrophenyl and 7-nitrobenzo[c] [1,2,5]oxadiazol-4-yl groups, respectively. Probes 1b and 1c gave off-on type responses with 169- and 17-fold fluorescent enhancements at 639 nm with H2S. Thei...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Wu MX, Sha XL, Wei XR, Sun R, Chen Y, Gao J, Xu YJ, Ge JF Tags: Anal Chim Acta Source Type: research

Metal-organic framework (MOF-5) coated SERS active gold gratings: A platform for the selective detection of organic contaminants in soil.
Abstract In this work, we proposed the functionalization of a surface plasmon-polariton (SPP)-supported gold grating surface with the metal-organic framework (MOF-5) for sensitive, selective and reproducible surface-enhanced Raman scattering (SERS) detection of organophosphorus pesticides. Homogeneous distribution of plasmon intensity along the Au grating surface ensures the high reproducibility of SERS results (deviation of Raman peak intensity does not exceed the 4% along the sample). The surface-assisted growth of thin MOF-5 film was accomplished in two steps procedure: (i) covalent grafting by 4-carboxyphenyl ...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Guselnikova O, Postnikov P, Elashnikov R, Miliutina E, Svorcik V, Lyutakov O Tags: Anal Chim Acta Source Type: research

Cyclic enzymatic amplification method for highly sensitive detection of nuclear factor-kappa B.
This study proposes a rapid and simple fluorescence sensing strategy for highly sensitive detection of a transcription factor, nuclear factor-kappa B (NF-κB). NF-κB binds to double-stranded DNA duplex, one of which is then protected from Exonuclease III (Exo III) digestion. An Exo III-mediated hydrolysis cycle on TaqMan probes is then triggered to achieve highly sensitive detection of NF-κB. This method can detect NF-κB with concentration as low as 45.6 pM. Furthermore, sequence-specific binding of NF-κB to DNA provides good selectivity. This method can be used for the direct quantification of...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Du K, Wu J, Pan A, Li D, Cui L, Peng C Tags: Anal Chim Acta Source Type: research

A novel fluorescence aptasensor based on mesoporous silica nanoparticles for selective and sensitive detection of aflatoxin B1.
Abstract Based on the mesoporous silica nanoparticles (MSN), a novel, simple and label-free aptamer biosensor was designed for the detection of aflatoxin B1 (AFB1). Here, the aptamers were used as molecular recognition probes and "gated molecules" while Rh6G was loaded into the interior of the particles as the signal probe. In the absence of AFB1, the "gate" was closed to prevent the leakage of the signal probe because of the immobilization of aptamers on the surface of MSN-NH2. With the presence of AFB1, the "gate" could be opened to release the signal probe for the specifical bindin...
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Tan H, Ma L, Guo T, Zhou H, Chen L, Zhang Y, Dai H, Yu Y Tags: Anal Chim Acta Source Type: research

Specific discrimination and universal signal amplification for RNA detection by coupling toehold exchange with RCA through nucleolytic conversion of a structure-switched hairpin probe.
In conclusion, we believe this method exhibits potential for both specific discrimination and universal signal amplification for RNA analysis in complex matrices. PMID: 31072482 [PubMed - in process] (Source: Analytica Chimica Acta)
Source: Analytica Chimica Acta - May 11, 2019 Category: Chemistry Authors: Yu W, Li J, Zuo C, Tao Y, Bai S, Li J, Zhang Z, Xie G Tags: Anal Chim Acta Source Type: research

A promising nanoprobe based on hydrophilic interaction liquid chromatography and immobilized metal affinity chromatography for capture of glycopeptides and phosphopeptides.
Abstract Glycosylation and phosphorylation are two important mechanisms in organism, both of which can finely regulate protein function respectively or simultaneously. Functional nanoprobes with various reversible interactions of aiming at glycan or phosphate group have been advanced dramatically, however, the comprehensive analysis towards them is largely restricted by the challenge to capture glycopeptides and phosphopeptides at the same time from complex samples due to the limitation of nanoprobe functionalization. Here, we fabricate a promising nanoprobe using the hydrophilic l-cysteine and titanium ions to en...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Wang Z, Wang J, Sun N, Deng C Tags: Anal Chim Acta Source Type: research

High-sensitive immunosensing of protein biomarker based on interfacial recognition-induced homogeneous exponential transcription.
Abstract A novel and versatile immunosensing strategy was developed for ultrasensitive and specific detection of proteins by organically integrating interfacial specific target recognition and homogeneous transcription amplification. In principle, classic antigen-antibody sandwich structure on the microplate could realize the specific identification of target protein. Biotinylated DNA probe was subsequently introduced by streptavidin-biotin system as a bridge linking interfacial and homogeneous reaction. The biotinylated DNA initiated exponential transcription amplification in the solution, which converted per tar...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Teng J, Huang L, Zhang L, Li J, Bai H, Li Y, Ding S, Zhang Y, Cheng W Tags: Anal Chim Acta Source Type: research

Progress in low-field benchtop NMR spectroscopy in chemical and biochemical analysis.
Abstract The employment of spectroscopically-resolved NMR techniques as analytical probes have previously been both prohibitively expensive and logistically challenging in view of the large sizes of high-field facilities. However, with recent advances in the miniaturisation of magnetic resonance technology, low-field, cryogen-free "benchtop" NMR instruments are seeing wider use. Indeed, these miniaturised spectrometers are utilised in areas ranging from food and agricultural analyses, through to human biofluid assays and disease monitoring. Therefore, it is both intrinsically timely and important to high...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Grootveld M, Percival B, Gibson M, Osman Y, Edgar M, Molinari M, Mather ML, Casanova F, Wilson PB Tags: Anal Chim Acta Source Type: research

Multifunctional iron oxide-carbon hybrid nanoparticles for targeted fluorescent/MR dual-modal imaging and detection of breast cancer cells.
Abstract An efficient method for the highly sensitive and specific detection of cancer cells is crucial for the early diagnosis of cancer. In this work, we propose a one-pot approach to fabricating magnetic-fluorescent iron oxide-carbon hybrid nanomaterials (MCNP) with excellent stable, high quantum yield and excellent magnetic properties for breast cancer cells recognition and detection via magnetic resonance and multicolour fluorescence imaging. MCNPs were efficiently synthesised via one-pot, multi-component reactions of FeCl3, FeCl2•4H2O, citric acid and ethylenediamine in diethylene glycol. The MCNPs show...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Han C, Zhang A, Kong Y, Yu N, Xie T, Dou B, Li K, Wang Y, Li J, Xu K Tags: Anal Chim Acta Source Type: research

One-step discrimination of BCR/ABLp210 transcript isoforms directly from RNA extraction with fusion-triggered rolling circle amplification.
Abstract BCR/ABLp210 fusion gene, the characteristic biomarker of chronic myelogenous leukemia (CML), contains two different transcription isoforms, e13a2 and e14a2, which lead to differences in the pathological features and response to targeted drug. At present, there is short of simple and fast technology to distinguish these two transcript isoforms. In this paper, RNA fusion-triggered rolling circle amplification (RF-RCA) strategy was developed to distinguish e13a2 and e14a2 transcripts directly from RNA extraction in one step. The simultaneous binding of dumbbell template and corresponding primer with target f...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Luo N, Xia Q, Zhang L, Zhang Y, Huang L, Zhang Y, Zhao J, Ding S, Cheng W Tags: Anal Chim Acta Source Type: research

Liquid chromatographic isolation of individual carbohydrates from environmental matrices for stable carbon analysis and radiocarbon dating.
In this study, semi-preparative liquid chromatography with refractive index detection (HPLC-RI) was employed to produce pure carbohydrate targets for subsequent offline δ13C and Δ14C isotopic analysis. δ13C analysis was performed by elemental analyzer-isotope ratio mass spectrometer (EA-IRMS) whereas Δ14C analysis was performed by an innovative measurement procedure based on the direct combustion of the isolated fractions using an elemental analyzer coupled to the gas source of a mini carbon dating system (AixMICADAS). In general, four successive purifications with Na+, Ca2+, Pb2+, and Ca2+ cation-e...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Nouara A, Panagiotopoulos C, Balesdent J, Violaki K, Bard E, Fagault Y, Repeta DJ, Sempéré R Tags: Anal Chim Acta Source Type: research

Admicelles in open-tube capillaries for chromatography and electrochromatography.
Abstract Surfactant bilayers or admicelles at the solid surface-liquid interface inside 50-200 μm inner diameter (i.d.) open-tube fused-silica capillaries were developed as 'soft' stationary pseudophases for the liquid chromatographic (LC) separations of neutral and charged analytes. Admicelles were formed in-situ from buffered aqueous mobile phases with cetytrimethylammonium bromide at concentrations between the critical surface aggregation concentration and critical micelle concentration, which were determined by electroosmotic flow measurements using capillary electrophoresis. There were no micelles in the...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Tarongoy F, Haddad PR, Quirino JP Tags: Anal Chim Acta Source Type: research

Recent advances in the fabrication and application of nanomaterial-based enzymatic microsystems in chemical and biological sciences.
Abstract Novel enzymatic microsystems have strong prospects in chemical and biological analysis due to their low consumption of reagents, fast analysis time, easy manipulation and satisfactory portability. Nanomaterials (NMs) provide a favorable platform for integrating enzymes into microsystems with enhanced selectivity and sensitivity. Various NM-enzyme immobilization strategies applied in the fabrication of capillary-based and chip-based enzymatic microsystems are summarized in this manuscript. We focus on highlighting the advantages of employing NM-based enzymatic microsystems for enantioseparation, inhibitor ...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Hong T, Liu W, Li M, Chen C Tags: Anal Chim Acta Source Type: research

Disposable impedance-based immunosensor array with direct-laser writing platform.
Abstract Immunoassay is a powerful technique to identify and quantify biological molecules, which base on the specificity and selectivity of antigen-antibody interaction. Impedance-based immunosensor has recently shown a great potential to provide rapid and label-free detections. However, the conventional impedance-based immunosensors rely on dedicated electrochemical measurement interface which involves expensive fabrication procedures such as gold deposition and photolithography. In this work, we propose an ultra-low-cost and high processing efficiency platform for impedance-based immunosensing. With effortless ...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Jin K, Hu S, Su Y, Yang C, Li J, Ma H Tags: Anal Chim Acta Source Type: research

Distinguishing the glycan isomers 2,3-sialyllactose and 2,6-sialyllactose by voltammetry after modification with osmium(VI) complexes.
ná V Abstract Altered glycosylation is a universal feature of cancer cells and certain glycans are well-known markers of tumor progression. In this work we studied two glycan isomers, 2,3-sialyllactose (3-SL) and 2,6-sialyllactose (6-SL), frequently appearing in glycoproteins connected with cancer. A combination of square wave voltammetry and glycan modification with osmium(VI) N,N,N',N'-tetramethylethylenediamine (Os(VI)tem) allowed to distinguish between these regioisomers, since the 6-SL molecule can bind three Os(VI), while the 3-SL only two Os(VI) moieties, as experiments using capillary electrophoresi...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Trefulka M, Černocká H, Fojt L, Paleček E, Ostatná V Tags: Anal Chim Acta Source Type: research

A multiplex liquid chromatography tandem mass spectrometry method for the quantification of seven therapeutic monoclonal antibodies: Application for adalimumab therapeutic drug monitoring in patients with Crohn's disease.
We describe an electrospray ionization LC-MS/MS method for the simultaneous quantification of seven mAbs (adalimumab, cetuximab, infliximab, rituximab, secukinumab, tocilizumab, and trastuzumab) in human plasma. Sample preparation was performed using protein-G purification and trypsin digestion to obtain proteotypic peptides. We retrospectively measured the adalimumab concentration in 65 plasma samples from 56 CD patients and determined the adalimumab therapeutic cut-off concentration associated with biological remission. Calibration curves were linear from 1 to 100 μg mL-1, except for rituximab (5-100 μg mL-...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Willeman T, Jourdil JF, Gautier-Veyret E, Bonaz B, Stanke-Labesque F Tags: Anal Chim Acta Source Type: research

Determination of picomolar concentrations of thiol compounds in natural waters and biological samples by tandem mass spectrometry with online preconcentration and isotope-labeling derivatization.
We present a sensitive, selective and robust method for the determination of 14 thiol compounds in aqueous samples. Thiols were derivatized with ω-bromoacetonylquinolinium bromide (BQB) and its deuterium labeled equivalent D7-ω-bromoacetonylquinolinium bromide (D7). Derivatized thiols were preconcentrated by online solid-phase extraction (SPE) followed by liquid chromatography separation and electrospray ionization tandem mass spectrometry determination (SPE/LC-ESI-MS/MS). The robustness of the method was validated for wide ranges in pH, salinity, and concentrations of sulfide and dissolved organic carbon (DOC)...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Liem-Nguyen V, Huynh K, Gallampois C, Björn E Tags: Anal Chim Acta Source Type: research

Removal of false positive features to generate authentic peak table for high-resolution mass spectrometry-based metabolomics study.
In this study, a method to remove false positive features (rFPF) was developed to improve the quality of the peak table. rFPF recognizes real peak profiles based on the information entropy and statistical correlation, and eliminates false positive features from non-sample sources and noises. A standard mixture with 42 standards (14 isotopic labeled internal standards and 28 common standards) and a urine sample were applied to evaluate the effectiveness of the rFPF method. The analysis results of metabolite standards showed that more than 92% false positive features were removed by rFPF, but target standards completely rema...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Ju R, Liu X, Zheng F, Zhao X, Lu X, Zeng Z, Lin X, Xu G Tags: Anal Chim Acta Source Type: research

Visualizing Nitric oxide in mitochondria and lysosomes of living cells with N-Nitrosation of BODIPY-based fluorescent probes.
Abstract Nitric oxide (NO), a ubiquitous gasotransmitter which plays critical roles in cardiovascular, nervous, and immune systems related diseases, is closely related in the physiological and pathological processes of mitochondria and lysosomes. Thus, monitoring NO in mitochondria or lysosomes is very meaningful for NO related chemical biology. Herein, we rationally designed four NO probes, BDP-NO, Mito-NO-T, Mito-NO and Lyso-NO, based on BODIPY dye substituted at meso position with 5-amino-2-methoxy-phenyl scaffold. These four probes all showed fast fluorescence off-on response toward NO with excellent selectivi...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Yu Z, Zhou J, Dong X, Zhao W, Chen Z Tags: Anal Chim Acta Source Type: research

Functionalized polymeric magnetic nanoparticle assisted SERS immunosensor for the sensitive detection of S.  typhimurium.
Functionalized polymeric magnetic nanoparticle assisted SERS immunosensor for the sensitive detection of S. typhimurium. Anal Chim Acta. 2019 Aug 27;1067:98-106 Authors: Chattopadhyay S, Sabharwal PK, Jain S, Kaur A, Singh H Abstract The quest for detecting bacteria has gained momentum in food and beverage industry for preventing spoilage of products to maintain requisite quality. The present paper describes the development of a SERS immunosensor for the detection of model pathogen, S. typhimurium using strategically synthesized functionalized polymeric magnetic nanoparticles (FPMNPs) as eff...
Source: Analytica Chimica Acta - May 4, 2019 Category: Chemistry Authors: Chattopadhyay S, Sabharwal PK, Jain S, Kaur A, Singh H Tags: Anal Chim Acta Source Type: research

Generic extraction medium: From highly polar to non-polar simultaneous determination.
Abstract Sample preparation for non-target analysis is challenging due to the difficulty in the extraction of polar and non-polar analytes simultaneously. Most commercial solid sorbents lack the proper comprehensiveness for extraction of analytes with different physiochemical properties. A possible key is the combination of hydrophobic polymer and hydrophilic surface functional groups in solid based extraction methods in order to generate the susceptibility for retaining both polar and non-polar analytes. To pursue this goal, in this study, four polar groups including NH2, NO2, COOH, and COCH3 were chemically boun...
Source: Analytica Chimica Acta - April 29, 2019 Category: Chemistry Authors: Zeinali S, Khalilzadeh M, Bagheri H Tags: Anal Chim Acta Source Type: research

Flow-through colorimetric assay for detection of nucleic acids in plasma.
Abstract A flow-through colorimetric assay for detection of nucleic acids in plasma is reported. The proposed assay features an array of four polyvinylidene fluoride (PVDF) membranes impregnated with cationic poly (3-alkoxy-4-methylthiophene) (PT) as an optical reporter. The sensing strategy is based on monitoring the changes in optical properties of PT, upon complexation with target nucleic acids in the presence and in the absence of their corresponding complementary peptide nucleic acids (PNAs). As a proof of concept, the proposed methodology is validated using two biomarkers; lung cancer associated microRNA (mi...
Source: Analytica Chimica Acta - April 29, 2019 Category: Chemistry Authors: Ammanath G, Yeasmin S, Srinivasulu Y, Vats M, Cheema JA, Nabilah F, Srivastava R, Yildiz UH, Alagappan P, Liedberg B Tags: Anal Chim Acta Source Type: research

On-off-on relay fluorescence recognition of ferric and fluoride ions based on indicator displacement in living cells.
Abstract A new boronic acid derivative functionalized with a 4-(3-(4-(4,5-diphenyl-1H-imidazole-2-yl)phenyl)-1,2,4-oxadiazol-5-yl)phenyl (IOP) moiety was synthesized for use as a sequential "on-off-on"-type relay fluorescence probe for Fe3+ ions and F- ions with high selectivity and sensitivity under physiological conditions. The introduction of Fe3+ to IOP boronic acid (IOPBA) formed an Fe3+IOPBA complex, which led to quenching of the blue fluorescence intensity at 458 nm. The lowest-energy conformation of IOPBA was theoretically predicted to adopt an extended structure, and the Fe3+ ion in the Fe3+IO...
Source: Analytica Chimica Acta - April 29, 2019 Category: Chemistry Authors: Selvaraj M, Rajalakshmi K, Nam YS, Lee Y, Song JW, Lee HJ, Lee KB Tags: Anal Chim Acta Source Type: research

A fluorescence-displacement assay using molecularly imprinted polymers for the visual, rapid, and sensitive detection of the algal metabolites, geosmin and 2-methylisoborneol.
Abstract A visual, rapid, and sensitive method for the detection of two algal metabolites, geosmin (GSM) and 2-methylisoborneol (2-MIB) using a competitive displacement technique based on molecular imprinted polymers (MIPs) and fluorescent tags was developed. In this method, fluorescent tags that bind to synthetic receptor sites of MIPs were designed and synthesised. In the presence of target analytes (geosmin and 2-methylisoborneol respectively), the tags are displaced leading to fluorescence signals. The MIPs were derived from the polymerisation of functional monomers and crosslinkers in the presence of suitable...
Source: Analytica Chimica Acta - April 29, 2019 Category: Chemistry Authors: Li C, Ngai MH, Reddy KK, Leong SCY, Tong YW, Chai CLL Tags: Anal Chim Acta Source Type: research

Single cell analysis for elucidating cellular uptake and transport of cobalt curcumin complex with detection by time-resolved ICPMS.
Abstract It is of great importance to elucidate the fate of drugs, e.g., their cellular uptake, transport and metabolism/excretion at single cell level. In the present work, cellular uptake and excretion of curcumin in HepG2 and MCF-7 cells were investigated by measuring 59Co in a curcumin cobalt complex ([Co(tpa)(cur)](ClO4)2) with inductively coupled plasma mass spectrometry (ICPMS). The uptake and distribution pattern of the metal drug complex in single cells were thoroughly studied, demonstrating extremely large discrepancy of uptake behavior among individual cells. The complex concentration-dependent uptake...
Source: Analytica Chimica Acta - April 29, 2019 Category: Chemistry Authors: Sun QX, Wei X, Zhang SQ, Chen ML, Yang T, Wang JH Tags: Anal Chim Acta Source Type: research

A sensitive ratiometric fluorescent probe for quantitive detection and imaging of alkaline phosphatase in living cells.
We report a sensitive fluorescence probe Ratio-ALP for in vivo ratiometric imaging of alkaline phosphatase (ALP). The probe was designed by conjugating a naphthalimide with a phosphate group as the responsive moiety for enzymatic reactions. The fluorescence intensity ratio displayed a linear relationship against the concentration of ALP in the concentration range from 0 to 200 U/L, its LOD is as low as 0.25 U/L. Ratio-ALP has good selectivity and sensitivity, high cell permeability, and low cytotoxicity. Furthermore, probe Ratio-ALP was also successfully applied to image endogenous ALP activity in living cells. P...
Source: Analytica Chimica Acta - April 29, 2019 Category: Chemistry Authors: Gao C, Zang S, Nie L, Tian Y, Zhang R, Jing J, Zhang X Tags: Anal Chim Acta Source Type: research

Mixed-mode liquid chromatography for the rapid analysis of biocatalytic glucaric acid reaction pathways.
Abstract Glucaric acid (GlucA) has been identified as one of the top 10 potential bio-based chemicals for replacement of oil-based chemicals. Several synthetic enzyme pathways have been engineered in bacteria and yeast to produce GlucA from glucose and myo-inositol. However, the yields and titres achieved with these systems remain too low for the requirements of a bio-based GlucA industry. A major limitation for the optimisation of GlucA production via synthetic enzymatic pathways are the laborious analytical procedures required to detect the final product (GlucA) and pathway intermediates. We have developed a nov...
Source: Analytica Chimica Acta - April 29, 2019 Category: Chemistry Authors: Petroll K, Care A, Waterstraat M, Bergquist PL, Sunna A Tags: Anal Chim Acta Source Type: research

Evaluation of different adsorbent materials for the untargeted and targeted bacterial VOC analysis using GC ×GC-MS.
Evaluation of different adsorbent materials for the untargeted and targeted bacterial VOC analysis using GC×GC-MS. Anal Chim Acta. 2019 Aug 20;1066:146-153 Authors: Franchina FA, Purcaro G, Burklund A, Beccaria M, Hill JE Abstract The analysis of bacterial volatile organic compounds has gained attraction as a non-invasive way to identify disease-causing organisms, given that bacteria have unique metabolisms and volatile metabolic byproducts. In the present research, different adsorbent materials (Carbopack Y, X, B, Carboxen 1000 and Tenax TA), packed singularly or in combination, were compared i...
Source: Analytica Chimica Acta - April 29, 2019 Category: Chemistry Authors: Franchina FA, Purcaro G, Burklund A, Beccaria M, Hill JE Tags: Anal Chim Acta Source Type: research

NMR analysis of the Fischer-Tropsch wastewater: Combination of 1D selective gradient TOCSY, 2D DOSY and qNMR.
Abstract The Fischer-Tropsch (FT) process is a practical approach to convert synthesis gas (CO and H2) into hydrocarbons and oxygenates, and these product mixtures are usually well-characterized. However, the analysis of Fischer-Tropsch waste water (FTW) is still somewhat underdeveloped and the exact composition of FTW remains unclear. Herein, various qualitative NMR techniques, especially diffusion-ordered spectroscopy (DOSY) and one dimension (1D) selective gradient total correlation spectroscopy (SelTOCSY) were strategically applied in the analysis of FTW. The NMR results show that the DOSY technique can pseudo...
Source: Analytica Chimica Acta - April 29, 2019 Category: Chemistry Authors: Ma H, Pedersen CM, Zhao Q, Lyu Z, Chang H, Qiao Y, Hou X, Wang Y Tags: Anal Chim Acta Source Type: research