13,342 results match your criteria Analyst[Journal]


Autarkic desorption electrospray ionization source for on-site analysis of consumer goods.

Analyst 2020 Jul 6. Epub 2020 Jul 6.

Institute of Inorganic and Analytical Chemistry, Justus Liebig University Giessen, Germany.

A general-purpose desorption electrospray ionization (DESI) source is presented which is not bound to the laboratory site. It allows autarkic operation for a few hours and can be connected to different types of (autarkic or non-autarkic) mass spectrometers via an atmospheric-pressure interface. Technical characteristics are described as well as results from direct surface analysis of consumer goods such as plastics, fruit peels or pills, or from living objects such as human skin, demonstrating the detection of various target compounds such as plasticizers, pesticides, drugs or sun blockers. Read More

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http://dx.doi.org/10.1039/d0an00713gDOI Listing

A fluorescent probe bearing two reactive groups discriminates between fluoride-containing G series and sulfur-containing V series nerve agents.

Analyst 2020 Jul 6. Epub 2020 Jul 6.

Institute of Chemical Defence, Beijing, 102205, China.

Herein, we present an approach to design a fluorescent molecule for detection and discrimination of fluoride-containing G series and sulfur-containing V series nerve agents. FP1 bearing two reactive groups can react with fluorides and thiols from the two types of nerve agents and generate different products with obvious and diverse fluorescences, which will be helpful when dealing with terrorist crises. Read More

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http://dx.doi.org/10.1039/d0an00878hDOI Listing

Portable glucose meter-utilized label-free and washing-free telomerase assay.

Analyst 2020 Jul 6. Epub 2020 Jul 6.

Department of Chemical and Biomolecular Engineering (BK21+ Program), KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea.

We herein describe a portable glucose meter (PGM)-utilized label-free and washing-free method for the facile determination of telomerase activity that relies on the kinase-catalyzed cascade enzymatic reaction (KCER) that transduces the telomerase activity to the glucose level. In the sensor, the telomerase that elongates telomere sequences ((TTAGGG)n) from the 3'-terminus of telomerase substrate primer (TSP) consumes deoxynucleoside triphosphate (dNTP), which serves as a phosphate source for KCER promoted by hexokinase and pyruvate kinase. Thus, the presence of telomerase protects KCER from working effectively, resulting in the maintenance of an initial, high glucose level that is readily determined using hand-held PGM. Read More

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http://dx.doi.org/10.1039/d0an00655fDOI Listing

Genetically encoded biosensors for the detection of rapamycin: toward the screening of agonists and antagonists.

Analyst 2020 Jul 3. Epub 2020 Jul 3.

Department of Biomedical Engineering (BK21 plus), Dongguk University, Seoul 04620, Korea.

Biosensors are valuable tools for the rapid screening of biological targets with high sensitivity and specificity. It is important to screen biological events in their native context for pharmacological and toxicological applications. However, in vitro biosensors often require purified probes and targets for screening, thus providing limited information on the biological activities of targets in their native environment. Read More

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http://dx.doi.org/10.1039/d0an01116aDOI Listing

Tetrakis(4-aminophenyl) ethene-doped perylene microcrystals with strong electrochemiluminescence for biosensing applications.

Analyst 2020 Jul 3. Epub 2020 Jul 3.

School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.

Perylene and its derivatives, as classical organic polycyclic aromatic hydrocarbon (PAH) ECL materials, have attracted extensive attention due to their excellent photoelectric activity and good structural controllability. As is well-known, the molecular structure of perylene is composed of five coplanar aromatic rings. There are intense π-π stacking interactions between perylene molecules, which lead to their aggregation and poor solubility in aqueous media. Read More

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http://dx.doi.org/10.1039/d0an00997kDOI Listing

Boronic acid-functionalized mesoporous magnetic particles with a hydrophilic surface for the multimodal enrichment of glycopeptides for glycoproteomics.

Analyst 2020 Jul 3. Epub 2020 Jul 3.

Institutes of Biomedical Sciences & Minhang hospital, Fudan University, Shanghai, 200032, China.

Glycosylation is an important mechanism of secondary protein processing. Large-scale profiling of glycopeptides released by proteolytic digestion of glycoproteins from biologic samples with complex compositions is limited due to their low abundance. Herein, we present a multimodal material based on boronic acid-modified mesoporous magnetic particles with a hydrophilic surface and enlarged pores around 10 nm. Read More

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http://dx.doi.org/10.1039/d0an00648cDOI Listing

In situ based surface-enhanced Raman spectroscopy (SERS) for the fast and reproducible identification of PHB producers in cyanobacterial cultures.

Analyst 2020 Jul 2. Epub 2020 Jul 2.

Austrian Biotech University of Applied Sciences, Konrad Lorenz-Straße 10, 3430 Tulln, Austria.

The production of polyhydroxybutyrate (PHB) by autotrophic fermentation of cyanobacteria has received increasing interest in the light of carbon emission reducing process strategies. Biotechnological approaches are in development to optimize the yield of PHB, including adapted cultivation media, characterized by a limitation of key nutrients: cyanobacteria accumulate PHB as energy storage molecules under limited growth conditions. Since there is an increasing demand for fast, simple and reliable analytics, we report the establishment of surface enhanced Raman spectroscopy (SERS) as a suitable monitoring tool for up scaled PHB production processes. Read More

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http://dx.doi.org/10.1039/d0an00969eDOI Listing

Sensitive determination of formamidopyrimidine DNA glucosylase based on phosphate group-modulated multi-enzyme catalysis and fluorescent copper nanoclusters.

Analyst 2020 Jul 2. Epub 2020 Jul 2.

Jiangsu Collaborative Innovation Center of Biomedical Functional Materials and Jiangsu Key Laboratory of Biofunctional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, P. R. China.

In this work, a method for quantifying the activity of formamidopyrimidine DNA glucosylase (Fpg) was designed based on phosphate group (P)-modulated multi-enzyme catalysis and fluorescent copper nanoclusters (CuNCs). By eliminating 8-oxoguanine from double-stranded DNA, Fpg generates a nick with P at both 3' and 5' termini. Subsequently, part of the DNA is digested by 5'P-activated lambda exonuclease (λ Exo), and the generated 3'P disables exonuclease I (Exo I), resulting in the generation of single-stranded DNA containing poly(thymine) (poly(T)). Read More

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http://dx.doi.org/10.1039/d0an00928hDOI Listing

A hybrid system integrating xylose dehydrogenase and NAD coupled with PtNPs@MWCNTs composite for the real-time biosensing of xylose.

Analyst 2020 Jul 2. Epub 2020 Jul 2.

Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin, 300308, P. R. China. and School of Chemical Engineering, University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing, 100049, P. R. China.

The wide application of xylose in the food, beverage, and pharmaceutical industries, as well as in the booming field of biorefinery, raises the demand for a rapid, accurate, and real-time xylose-sensing technique to rival the conventional methods based on chromatography, spectroscopy, and electrochemical analysis using non-specific enzymes or abiotic catalysts. Herein, a hybrid system comprising polyethylene glycerol swing-arm-tethered NAD+ and xylose dehydrogenase (XDH), coupled with platinum nanoparticles deposited on carbon nanotubes (PtNPs@MWCNTs), was constructed for the real-time sensing of xylose. The use of the PtNPs@MWCNTs composite enhanced the sensitivity of the electric response and reduced the oxidation potential of NADH significantly. Read More

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http://dx.doi.org/10.1039/d0an00880jDOI Listing

Upconversion nanoparticle and gold nanocage satellite assemblies for sensitive ctDNA detection in serum.

Analyst 2020 Jul 2. Epub 2020 Jul 2.

Key Laboratory of Biomedical Engineering of Fujian Province University/Research Center of Biomedical Engineering of Xiamen, Department of Biomaterials, College of Materials, Xiamen University, Xiamen 361005, P.R. China. and State Key Lab of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, P.R. China.

A rapid molecular diagnostic technique targeting circulating tumor DNA (ctDNA) has become one of the most clinically significant liquid biopsy methods for non-invasive and timely diagnosis of cancer. Herein, a sensitive detection system of ctDNA based on a fluorescence resonance energy transfer (FRET) system using upconversion nanoparticles (UCNPs) and gold nanocages (AuNCs) was constructed. Through the doping of Yb and Tm ions, the excitation and emission wavelengths of UCNPs were adjusted to 980 nm and 806 nm, respectively. Read More

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http://dx.doi.org/10.1039/d0an00701cDOI Listing

A Cas12a-mediated cascade amplification method for microRNA detection.

Analyst 2020 Jul 1. Epub 2020 Jul 1.

Laboratory of Biosystem and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China. and Institute of Engineering Biology and Health, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China and School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832000, Xinjiang, China.

MicroRNAs (miRNAs) play a vital role in various biological processes and act as important biomarkers for clinical cancer diagnosis, prognosis, and therapy. Here, we took advantage of Cas12a trans-cleavage activity to develop an enzyme-assisted cascade amplification method for isothermal miRNA detection. A target miRNA-initiated ligation reaction would allow for the production of transcription templates that triggered the transcriptional amplification of RNA strands. Read More

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http://dx.doi.org/10.1039/d0an00370kDOI Listing

Influence of interfering co-appearing container peaks on the accuracy of direct quantitative Raman measurement of a sample in a plastic container.

Analyst 2020 Jul 1. Epub 2020 Jul 1.

Department of Chemistry and Research Institute for Convergence of Basic Science, Hanyang University, Seoul 04763, Republic of Korea.

The axially perpendicular offset (APO) scheme was previously demonstrated as a versatile scheme able to minimize or eliminate the glass background in the direct and non-sampling Raman measurement of an ethanol sample housed in a glass bottle. Alternatively, when directly analyzing a sample housed in a plastic container, another typical container yielding strong Raman peaks itself, the Raman peaks of both the container and the housed sample are unavoidably present together in a collected spectrum. Therefore, a crucial issue to investigate under this situation is how the magnitude of the co-appearing container peaks influences the accuracy for quantitative analysis of the housed sample. Read More

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http://dx.doi.org/10.1039/d0an00741bDOI Listing

Engineering at the nano-bio interface: harnessing the protein corona towards nanoparticle design and function.

Analyst 2020 Jul 1. Epub 2020 Jul 1.

Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California 94720, USA. and California Institute for Quantitative Biosciences, QB3, University of California, Berkeley, Berkeley, California 94720, USA and Innovative Genomics Institute (IGI), Berkeley, California 94720, USA and Chan-Zuckerberg Biohub, San Francisco, California 94158, USA.

Unpredictable and uncontrollable protein adsorption on nanoparticles remains a considerable challenge to achieving effective application of nanotechnologies within biological environments. Nevertheless, engineered nanoparticles offer unprecedented functionality and control in probing and altering biological systems. In this review, we highlight recent advances in harnessing the "protein corona" formed on nanoparticles as a handle to tune functional properties of the protein-nanoparticle complex. Read More

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http://dx.doi.org/10.1039/d0an00633eDOI Listing

Luminescent probes for hypochlorous acid in vitro and in vivo.

Analyst 2020 Jul 1. Epub 2020 Jul 1.

State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China.

HClO/ClO- is the most effective antibacterial active oxygen in neutrophils. However, its excessive existence often leads to the destruction of human physiological mechanisms. In recent years, the developed luminescent probes for the detection of HClO/ClO- are not only conducive to improve the sensitivity and selectivity of HClO/ClO- detection, but also play a crucial role in understanding the biological functions of HClO/ClO-. Read More

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http://dx.doi.org/10.1039/d0an00645aDOI Listing

A novel solution-gated graphene transistor biosensor for ultrasensitive detection of trinucleotide repeats.

Analyst 2020 Jul 1. Epub 2020 Jul 1.

Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, No. 368 Youyi Avenue, Wuchang, Wuhan 430062, China.

A new way to detect GAA trinucleotide repeats (TNRs) based on a solution-gated graphene transistor (SGGT) with high performance was developed. Friedreich's ataxia (FRDA) is a neurodegenerative disease where the first intron of the frataxin (FXN) gene exhibits an extended GAA repeat region. Herein, a SGGT biosensor was constructed based on G-quadruplex DNAzymes and graphene channels. Read More

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http://dx.doi.org/10.1039/d0an00205dDOI Listing

Electro-hydrodynamic extraction of DNA from mixtures of DNA and bovine serum albumin.

Analyst 2020 Jul 1. Epub 2020 Jul 1.

Department of Chemical Engineering, University of Florida, Gainesville, FL, USA.

We report separation of genomic DNA (48 kbp) from bovine serum albumin (BSA) by the electro-hydrodynamic coupling between a pressure-driven flow and a parallel electric field. Electro-hydrodynamic extraction exploits this coupling to trap DNA molecules at the entrance of a microfluidic contraction channel, while allowing proteins and salts to be flushed from the device. Samples (10 μL) containing λ-DNA (1 ng) and BSA (0. Read More

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http://dx.doi.org/10.1039/d0an00961jDOI Listing

Two-dimensional identification and localization of isomers in crystallin peptides using TWIM-MS.

Analyst 2020 Jul 1. Epub 2020 Jul 1.

Department of Chemistry, University of California, Riverside, California 92521, USA.

Recent studies have illuminated connections between spontaneous chemical reactions that cause isomerization at specific protein residues and various age-related diseases including cataracts and Alzheimer's. These discoveries provide impetus for better analytical methods to detect and characterize isomerization in proteins, which will enable a more complete understanding of the underlying relationship between these modifications and biology. Herein we employ a two-dimensional approach for identification of peptides isomers that also includes pinpointing of the modified residue. Read More

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http://dx.doi.org/10.1039/d0an01036gDOI Listing

Correction: A paper-supported sandwich immunosensor based on upconversion luminescence resonance energy transfer for the visual and quantitative determination of a cancer biomarker in human serum.

Analyst 2020 Jul 1. Epub 2020 Jul 1.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.

Correction for 'A paper-supported sandwich immunosensor based on upconversion luminescence resonance energy transfer for the visual and quantitative determination of a cancer biomarker in human serum' by Mengyuan He et al., Analyst, 2020, 145, 4181-4187, DOI: 10.1039/c9an02307k. Read More

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http://dx.doi.org/10.1039/d0an90071kDOI Listing

A versatile dendritical amplification photoelectric biosensing platform based on BiS nanorods and a perylene-based polymer for signal "on" and "off" double detection of DNA.

Analyst 2020 Jul 1. Epub 2020 Jul 1.

Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE; Shandong Key Laboratory of Biochemical Analysis; Key Laboratory of Analytical Chemistry for Life Science in Universities of Shandong; College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.

A novel versatile dendritical amplification photoelectric (PEC) biosensing platform using Bi2S3 nanorods and perylene-based polymer (PTC-NH2) as double signal probes is proposed for the detection of trace target DNA. Bi2S3 nanorods as efficient photoactive materials were firstly immobilized on the Au nanoparticle (NP) modified electrode and generated a high PEC signal. Exonuclease III (Exo III)-assisted target recycling generated a large number of DNA product chains (PC), PC hybridized with hairpin DNA (H1) on AuNPs/Bi2S3/ITO, and then triggered rolling circle amplification (RCA) and the hybridization chain reaction (HCR) to form the dendritic structure with abundant DNA duplexes. Read More

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http://dx.doi.org/10.1039/d0an01040eDOI Listing

Infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) mass spectrometry imaging analysis of endogenous metabolites in cherry tomatoes.

Analyst 2020 Jun 30. Epub 2020 Jun 30.

FTMS Laboratory for Human Health Research, Department of Chemistry, USA. and Department of Plant and Microbial Biology, USA and Molecular Education, Technology, and Research Innovation Center (METRIC), North Carolina State University, Raleigh, NC 27695, USA.

We report the spatially resolved metabolic profiling of cherry tomatoes using infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI), a mass spectrometry imaging (MSI) technique that operates at ambient conditions and requires no sample derivatization. Tomatoes were flash frozen, cryosectioned and imaged with adequate spatial resolution to distinguish between the major tissue structures of a tomato including the skin, mesocarp, endocarp, locular tissue, septum, placenta, seed and seed coating. Metabolites were imaged from 100-1200 m/z, enabling significant coverage of a diverse array of metabolites including amino acids and lipids along with the major secondary metabolite classes: terpenes, phenolics, glycosides, and alkaloids. Read More

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http://dx.doi.org/10.1039/d0an00818dDOI Listing

Rapid and selective detection of recombinant human erythropoietin in human blood plasma by a sensitive optical sensor.

Analyst 2020 Jun 29. Epub 2020 Jun 29.

Queensland University of Technology (QUT), School of Chemistry and Physics, 2 George street QLD, 4000, Australia. and Centre for Material Science, Queensland University of Technology (QUT), 2 George street QLD, 4000, Australia.

Recombinant human erythropoietin (rHuEPO) is an important hormone drug that is used to treat several medical conditions. It is also frequently abused by athletes as a performance enhancing agent at sporting events. The time window of the rHuEPO in blood is short. Read More

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http://dx.doi.org/10.1039/d0an00972eDOI Listing

Rapid genotypic antibiotic susceptibility test using CRISPR-Cas12a for urinary tract infection.

Analyst 2020 Jun 29. Epub 2020 Jun 29.

Department of Mechanical Engineering, University of California, Berkeley, Berkeley, CA 94760, USA.

The current clinical protocol to conduct a bacterial antibiotic susceptibility test (AST) requires at least 18 hours, and cannot be accomplished during a single visit for patients. Here, a new method based on the technique of CRISPR-Cas12a is utilized to accomplish a bacterial genotypic AST within one hour with good accuracy. Two amplification approaches are employed and compared: (1) enriching the bacterial concentration by culturing in growth media; and (2) amplifying target DNA from raw samples by recombinase polymerase amplification (RPA). Read More

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http://dx.doi.org/10.1039/d0an00947dDOI Listing

An innovative blood plasma separation method for a paper-based analytical device using chitosan functionalization.

Analyst 2020 Jun 29. Epub 2020 Jun 29.

Department of Bionanotechnology, Gachon University, Seongnam, 13120, Republic of Korea.

This study describes a microfluidic paper-based analytical device (μPAD) for separating plasma from whole blood and measuring glucose concentration. A two-dimensional μPAD was fabricated by wax printing, using chromatographic paper and was functionalized by the incorporation of chitosan into the plasma separation zone. Red blood cells were isolated from whole blood in the plasma separation zone consisting of a chitosan polymer structure and a wax barrier. Read More

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http://dx.doi.org/10.1039/d0an00500bDOI Listing

Triggered peroxidase-like activity of Au decorated carbon dots for colorimetric monitoring of Hg enrichment in Chlorella vulgaris.

Analyst 2020 Jun 29. Epub 2020 Jun 29.

Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, Northwest Normal University, Lanzhou, 730070, Gansu, China.

Developing a rapid, low-cost, and multimode detection method for heavy metal ions remains a compelling goal for many applications, including food safety, environmental and biological analysis. This study investigated the influence of Hg2+ on the peroxidase-like activity of gold nanoparticles (GNPs) decorated on carbon dots (CDs) from lysine (denoted as GNP@CDs). A new type of Hg2+-triggered peroxidase-like activity of GNP@CDs was discovered, which could catalyze the oxidation of the colorless 3,3',5,5'-tetramethylbenzidine (TMB) into blue TMB. Read More

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http://dx.doi.org/10.1039/d0an00930jDOI Listing

A new method to amplify colorimetric signals of paper-based nanobiosensors for simple and sensitive pancreatic cancer biomarker detection.

Analyst 2020 Jun 26. Epub 2020 Jun 26.

Department of Chemistry, University of Texas at El Paso, 500 West University Avenue, El Paso, Texas 79968, USA. and Biomedical Engineering, Border Biomedical Research Center, and Environmental Science & Engineering, University of Texas at El Paso, USA.

A low-cost, sensitive, and disposable paper-based immunosensor for instrument-free colorimetric detection of pancreatic cancer biomarker PEAK1 was reported for the first time by capitalizing the catalytic properties of gold nanoparticles in colour dye degradation. This simple signal amplification method enhances the detection sensitivity by about 10 fold. Read More

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http://dx.doi.org/10.1039/d0an00704hDOI Listing
June 2020
4.107 Impact Factor

Thermistors coated with molecularly imprinted nanoparticles for the electrical detection of peptides and proteins.

Analyst 2020 Jun 26. Epub 2020 Jun 26.

Newcastle University, School of Engineering, Merz Court, Claremont Road, NE1 7RU, Newcastle Upon Tyne, UK.

In this communication, molecularly imprinted nanoparticles (nanoMIPs) that are produced by solid-phase synthesis are functionalised onto thermistors via dip-coating. These thermistors are soldered onto a printed-circuit board to facilitate electrical detection. Subsequently, these are inserted into a home-made thermal device that can measure the selective binding of biomolecules to the nanoMIP layer via monitoring the thermal resistance (Rth) at the solid-liquid interface. Read More

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http://dx.doi.org/10.1039/d0an01046dDOI Listing

Simple and rapid nicotine analysis using a disposable silica nanochannel-assisted electrochemiluminescence sensor.

Analyst 2020 Jun 26. Epub 2020 Jun 26.

Key Laboratory of Study and Discovery of Small Targeted Molecules of Hunan Province, Department of Pharmacy, School of Medicine, Hunan Normal University, Changsha 410013, Hunan, China.

Nicotine analysis is essential to medicine, toxicology and the tobacco industry. However, no simple, portable and disposable method was developed to meet their demands. Here, we report a simple, rapid and disposable silica nanochannel (SAN)-based electrochemiluminescence (ECL) sensor for nicotine analysis by simply assembling a SAN electrode with a paper cover. Read More

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http://dx.doi.org/10.1039/d0an00588fDOI Listing

A target-mediated fuel-initiated molecular machine for high-sensitive fluorescence assay of the ZIKV gene via strand displacement reaction-based signal recovery and cycling amplification.

Analyst 2020 Jun 26. Epub 2020 Jun 26.

Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Jiangsu National Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts and Telecommunications, Nanjing, 210023, China.

Zika virus (ZIKV) is a serious threat to human health due to its widespread human arboviral infections, and early diagnosis is one of the keys to preventing infections from spreading, but there is a lack of highly sensitive and specific detection. In this work, a target-mediated fuel-initiated molecular machine was proposed for the high-sensitive fluorescence assay of the ZIKV gene via strand displacement reaction-based signal recovery and cycling amplification. The molecular machine was prepared by modifying AuNP surfaces with specially designed lock-like DNAs (LLDs). Read More

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http://dx.doi.org/10.1039/d0an00854kDOI Listing

Colorimetric discriminatory array for detection and discrimination of antioxidants based on HAuCl/3,3',5,5'-tetramethylbenzidine.

Analyst 2020 Jun 26. Epub 2020 Jun 26.

Department of Chemistry, Capital Normal University, Beijing, 100048, China.

Here, we report a simple but effective nose/tongue-mimic sensor array based on HAuCl4/3,3',5,5'-tetramethylbenzidine (TMB) for colorimetric discrimination and determination of antioxidants. Two concentrations of HAuCl4 were employed as receptor units to construct the colorimetric sensor array. The sensing strategy is based on the fact that HAuCl4 with different concentrations (0. Read More

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http://dx.doi.org/10.1039/d0an00617cDOI Listing

Phosphorylcholine-based encoded hydrogel microparticles with enhanced fouling resistance for multiplex immunoassays.

Analyst 2020 Jun 26. Epub 2020 Jun 26.

Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.

Due to the growing interest in multiplex protein detection, encoded hydrogel microparticles have received attention as a possible path to high performance multiplex immunoassays through a combination of high multiplexing capability and enhanced binding kinetics. However, their practical operation in real complex samples is still limited because polyethylene glycol, which is the main component of hydrogel particles, suffers from oxidative damage and relatively high fouling properties in biochemical solutions. Here, we introduce poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)-based encoded hydrogel microparticles to perform fouling-resistant multiplex immunoassays, where the anti-fouling characteristics are attributed to the zwitterionic PMPC. Read More

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http://dx.doi.org/10.1039/d0an00808gDOI Listing

Metabolite collision cross section prediction without energy-minimized structures.

Analyst 2020 Jun 25. Epub 2020 Jun 25.

Georgia Institute of Technology, School of Chemistry and Biochemistry, 901 Atlantic Drive, Atlanta, GA 30332, USA.

Matching experimental ion mobility-mass spectrometry data to computationally-generated collision cross section (CCS) values enables more confident metabolite identifications. Here, we show for the first time that accurately predicting CCS values with simple models for the largest library of metabolite cross sections is indeed possible, achieving a root mean square error of 7.0 Å2 (median error of ∼2%) using linear methods accesible to most researchers. Read More

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http://dx.doi.org/10.1039/d0an00198hDOI Listing

Deep learning for 'artefact' removal in infrared spectroscopy.

Analyst 2020 Jun 24. Epub 2020 Jun 24.

Leibniz Institute of Photonic Technology Jena (IPHT Jena), Member of Leibniz Health Technologies, 07745 Jena, Germany. and Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University of Jena, 07743 Jena, Germany.

It has been well recognized that infrared spectra of microscopically heterogeneous media do not merely reflect the absorption of the sample but are influenced also by geometric factors and the wave nature of light causing scattering, reflection, interference, etc. These phenomena often occur simultaneously in complex samples like tissues and manifest themselves as intense baseline profiles, fringes, band distortion and band intensity changes in a measured IR spectrum. The information on the molecular level contained in IR spectra is thus entangled with the geometric structure of a sample and the optical model behind it, which largely hinders the data interpretation and in many cases renders the Beer-Lambert law invalid. Read More

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http://dx.doi.org/10.1039/d0an00917bDOI Listing

Ultrasensitive detection of butyrylcholinesterase activity based on the inner filter effect of MnO nanosheets on sulfur nanodots.

Analyst 2020 Jun 24. Epub 2020 Jun 24.

Key Laboratory of Chemical Biology of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis, Ministry of Education, College of Chemistry & Environmental Science, Hebei University, Baoding 071002, China.

Butyrylcholinesterase (BChE) activity is an important index for a variety of diseases. In this work, a "turn-on" assay is proposed based on controlling the inner filter effect (IFE) of MnO2 nanosheets (NSs) on sulfur nanodots (S-dots). The fluorescence of S-dots is effectively quenched by the MnO2 NSs, due to the wide overlap of the emission spectrum of S-dots and absorption spectrum of MnO2 NSs, together with the superior light absorption capability of MnO2 NSs. Read More

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http://dx.doi.org/10.1039/d0an00939cDOI Listing

Aqueous two-phase system antibody confinement enables cost-effective analysis of protein analytes by sandwich enzyme-linked immunosorbent assay with minimal optical crosstalk.

Analyst 2020 Jun 24. Epub 2020 Jun 24.

School of Biomedical Engineering, Dalhousie University, Halifax, NS, Canada. and Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS, Canada.

An aqueous two-phase system formed from polyethylene glycol and dextran was used to uniformly coat the bottom surfaces of the wells of standard 96-well assay plates with capture and detection antibodies to improve the performance and cost-effectiveness of sandwich enzyme-linked immunosorbent assay (ELISA). Using this approach, limits of detection and linear dynamic range values comparable to those obtained for conventional sandwich ELISA were obtained using considerably lower antibody quantities due to the much lower reagent volumes required when antibodies are applied in a dextran solution beneath a polyethylene glycol overlay. Confinement of the antibody reagents to the bottom surfaces of the wells within the dextran phase also dramatically decreased the optical crosstalk present between neighboring wells when using transparent microplates. Read More

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http://dx.doi.org/10.1039/d0an00699hDOI Listing

Nanoparticle and microorganism detection with a side-micron-orifice-based resistive pulse sensor.

Analyst 2020 Jun 24. Epub 2020 Jun 24.

Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.

This paper presents the detection of nanoparticles and microorganisms using a recently developed side-orifice-based resistive pulse sensor (SO-RPS). By decreasing the channel height of the detection section of the SO-RPS, the detection sensitivity was increased and an average signal to noise ratio (S/N) of about 3 was achieved for 100 nm polystyrene particles. It was also found that spherical particles generate symmetrical signals. Read More

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http://dx.doi.org/10.1039/d0an00679cDOI Listing

Fe detection, bioimaging, and patterning based on bright blue-fluorescent N-doped carbon dots.

Analyst 2020 Jun 23. Epub 2020 Jun 23.

Department of Chemistry and Chemical Engineering, Center of Environmental Science and Engineering Research, Shanxi University, Taiyuan, 030006, China.

Bright blue fluorescent N-doped carbon dots (N-CDs) with satisfactory yield (54%) were successfully fabricated by one-step hydrothermal treatment of astragalus. The obtained N-CDs possessed superior stability, solubility and high resistance to photo bleaching, and can be used as label-free nanosensors for the determination of Fe3+. The quantitative analysis of Fe3+ showed a linear range of 50 to 250 μM with the detection limit as low as 42 nM. Read More

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http://dx.doi.org/10.1039/d0an01042aDOI Listing

Simultaneous quantification of peroxidase and ascorbic acid in biosamples with an automatic system based on a Fe(iii)/methylthymol blue-carbon dot simulative enzyme.

Analyst 2020 Jun 23. Epub 2020 Jun 23.

West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu 610041, China.

Peroxidase (POD) and ascorbic acid (AsA) usually coexist in organisms to synergistically protect them from reactive oxygen damage, and their contents undergo dynamic changes under different physiological conditions. What's more, the response of POD-catalytic activity in spectrophotometry has to be corrected using the content of concomitant AsA because we found that there is an extinction reaction between AsA and chromogenic products obtained from POD catalysis. With these implications, by skilfully using the chromogenic and the extinction phenomena in the guaiacol/POD/H2O2 reaction, an automatic analysis system for simultaneous quantification of POD (73-440 U L-1) and AsA (4-60 mg L-1) was successfully established based on flow injection analysis (FIA). Read More

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http://dx.doi.org/10.1039/d0an00291gDOI Listing

A 3D porous graphene aerogel@GOx based microfluidic biosensor for electrochemical glucose detection.

Analyst 2020 Jun 23. Epub 2020 Jun 23.

School of Mechanical Engineering, and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing 211189, China.

As a chronic disease, diabetes may result in serious complications that endanger the health and life of patients. Accurate and real-time detection of blood sugar levels is of great significance for the prevention and treatment of diabetes. In this paper, an enzymatic electrochemical microfluidic biosensor for glucose detection was developed based on a three-dimensional (3D) porous graphene aerogel and glucose oxidase (GOx). Read More

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http://dx.doi.org/10.1039/d0an00681eDOI Listing

Microfluidic on-demand engineering of longitudinal dynamic self-assembly of particles.

Analyst 2020 Jun 23. Epub 2020 Jun 23.

School of Mechanical Engineering, and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing 211189, China.

The lack of a simple operable method for on-demand engineering of longitudinal dynamic self-assembly of particles is one of the main problems in employing particle manipulation in biomedical research studies. Herein, a viscoelasticity-induced self-assembling microfluidic system is proposed to increase the maneuverability and orderliness of longitudinal dynamic self-assembly of particles, and achieve the on-demand control of interparticle spacings and frequencies of particles passing through an outlet. In our microfluidic system, two kinds of functional microstructures and a side-channel were designed to preprocess randomly distributed particles allowing them not to aggregate but rather to evenly distribute, and realize the on-demand control of the particle volume concentration. Read More

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http://dx.doi.org/10.1039/d0an00653jDOI Listing

Quantitative H-NMR spectroscopy as an efficient method for identification and quantification of PVC, ABS and PA microparticles.

Analyst 2020 Jun 23. Epub 2020 Jun 23.

Institute of Integrated Natural Sciences, University Koblenz-Landau, Universitätsstr. 1, D-56070 Koblenz, Germany.

As an extension of the new, size-independent, fast and easy quantitative 1H-NMR (qNMR) spectroscopy as an alternative method for microplastic (MP) analysis we herein present the possibility to analyze three environmentally highly relevant MP particles by qNMR spectroscopy. The investigations cover polyvinyl chloride (PVC) powder with a size <50 μm, acrylonitrile butadiene styrene (ABS) granules with a size distribution of 100-300 μm, and polyamide (PA) fibres with a length of approx. 500 μm and a diameter of approx. Read More

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http://dx.doi.org/10.1039/d0an00879fDOI Listing

Recent advances in sensors for electrochemical analysis of nitrate in food and environmental matrices.

Analyst 2020 Jun 23. Epub 2020 Jun 23.

College of Science and Engineering, James Cook University, Townsville, Queensland 4811, Australia.

Nitrate is one of the most common contaminants in food and the environment and mainly arises from intense human activities. Electrochemical sensors have been considered as one of the most promising analytical tools for the rapid detection of nitrate in food and environmental matrices due to their quick response, high sensitivity, ease of operation and miniaturisation, and low sample and power consumption. In this review, we summarise advances in sensors for electrochemical analysis of nitrate over the past decade. Read More

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http://dx.doi.org/10.1039/d0an00823kDOI Listing

Development of a lateral flow immunoassay strip for rapid detection of IgG antibody against SARS-CoV-2 virus.

Analyst 2020 Jun 22. Epub 2020 Jun 22.

Jiangsu Provincial Center for Disease Control and Prevention, NHC Key laboratory of Enteric Pathogenic Microbiology, Nanjing, Jiangsu Province, P. R. China.

The ongoing worldwide SARS-CoV-2 epidemic clearly has a tremendous influence on public health. Molecular detection based on oral swabs was used for confirmation of SARS-CoV-2 infection. However, high false negative rates were reported. Read More

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http://dx.doi.org/10.1039/d0an00629gDOI Listing

LC-MS analysis of p-aminosalicylic acid under electrospray ionization conditions manifests a profound solvent effect.

Analyst 2020 Jun 22. Epub 2020 Jun 22.

Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ 07030, USA.

Selected-ion recording (SIR) or multiple-reaction monitoring (MRM) protocols are widely employed for the quantification of targeted analytes by liquid chromatography-mass spectrometry (LC-MS). After chromatographic separation, analytes are desolvated and converted to gaseous ions usually by electrospray-ionization. The chromatographic peaks generated in this way are then integrated for quantification. Read More

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http://dx.doi.org/10.1039/d0an00680gDOI Listing

Stepwise elucidation of fluorescence based sensing mechanisms considering picric acid as a model analyte.

Analyst 2020 Jun 22. Epub 2020 Jun 22.

Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, Assam-781 039, India. and Centre for Nanotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam-781 039, India.

In most of the sensing systems, specific detection mechanisms are involved during the detection process for a certain analyte irrespective of probes. However, unlike that of various sensing analytes, the detection of the highly toxic and explosive picric acid (PA) analyte was found to involve significant types of distinct sensing mechanisms depending on the nature of probes. Moreover, in the past five years, apart from the plethora of fluorescent probes designed, a number of unique organic small molecules and polymers have been strategically developed at our laboratory for the detection of PA, wherein the involvement of several diverse mechanisms along with a few new mechanisms depending on the electronic and photophysical properties of the probes has been unveiled. Read More

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http://dx.doi.org/10.1039/d0an00732cDOI Listing

Characterization of N-linked intact glycopeptide signatures of plasma IgGs from patients with prostate carcinoma and benign prostatic hyperplasia for diagnosis pre-stratification.

Analyst 2020 Jun 22. Epub 2020 Jun 22.

Key Lab of Transplant Engineering and Immunology, MOH; West China-Washington Mitochondria and Metabolism Research Center; Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu 610041, China.

The discovery of novel non-invasive biomarkers for discriminating between prostate carcinoma (PCa) patients and benign prostatic hyperplasia (BPH) patients is necessary to reduce the burden of biopsies, avoid overdiagnosis and improve quality of life. Previous studies suggest that abnormal glycosylation of immunoglobulin gamma molecules (IgGs) is strongly associated with immunological diseases and prostate diseases. Hence, characterizing N-linked intact glycopeptides of IgGs that correspond to the N-glycan structure with specific site information might enable a better understanding of the molecular pathogenesis and discovery of novel signatures in preoperative discrimination of BPH from PCa. Read More

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http://dx.doi.org/10.1039/d0an00225aDOI Listing

A platform for multiplexed colorimetric microRNA detection using shape-encoded hydrogel particles.

Analyst 2020 Jun 22. Epub 2020 Jun 22.

Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.

We report a platform utilizing a reporter enzyme, which produces a chromogenic indigo precipitate that preferentially localizes within a hydrogel microparticle. The 3D network of the hydrogel maintains the rapid target binding kinetics found in solution, while multiplexed target detection is achieved through shape-encoding of the particles. Moreover, the precipitate-laden hydrogels can be imaged with a simple phone camera setup. Read More

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http://dx.doi.org/10.1039/d0an00938eDOI Listing

Gold nanoparticle-streptavidin conjugates for rapid and efficient screening of aptamer function in lateral flow sensors using novel CD4-binding aptamers identified through Crossover-SELEX.

Analyst 2020 Jun 22. Epub 2020 Jun 22.

Rhodes University Biotechnology Innovation Centre, Grahamstown, Eastern Cape, South Africa.

To decrease the burden of laborious and reagent-intensive screening of modified aptamers, their binding function requires assessment in assay formats compatible with the end diagnostic application. Here, we report on the use of an alternative and cost-effective approach: a rapid lateral flow assay (LFA) utilising streptavidin-conjugated gold nanoparticles (AuNP) as reporter molecules to screen novel ssDNA aptamers for their ability to detect CD4. Crossover-SELEX was employed to identify CD4-targeting aptamers from a ssDNA library enriched against a recombinant human CD4 protein (hCD4) conjugated to magnetic-beads and to endogenous CD4 expressed by U937 cells. Read More

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http://dx.doi.org/10.1039/d0an00634cDOI Listing
June 2020
4.107 Impact Factor

New barbituric acid derivatives for data encryption and decryption based on the mechanochromic fluorescence effect.

Analyst 2020 Jun 19. Epub 2020 Jun 19.

School of Chemical and Pharmaceutical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.

Two barbituric acid derivatives CB-Ph and CB-Me were synthesized, both of which show a strong aggregation induced emission (AIE) effect. It was found that these two compounds show almost the same absorption and emission spectra. As a result, they show the same yellow color in daylight and the same yellow-green color under UV at 365 nm. Read More

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http://dx.doi.org/10.1039/d0an00728eDOI Listing
June 2020
4.107 Impact Factor

Field induced fragmentation spectra from reactive stage-tandem differential mobility spectrometry.

Analyst 2020 Jun 19. Epub 2020 Jun 19.

Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM 88003, USA..

A planar tandem differential mobility spectrometer was integrated with a middle reactive stage to fragment ions which were mobility selected in a first analyzer stage using characteristic compensation and separation fields. Fragmentation occurred in air at ambient pressure of 660 Torr (8.8 kPa) with electric fields of 10 to 35 kV cm-1 (E/N of 52 to 180 Td) between two 1 mm wide metal strips, located on each analyzer plate between the first and second mobility stages. Read More

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http://dx.doi.org/10.1039/d0an00665cDOI Listing

Preparation of a DNA-Tb-MOF conjugate as a time-resolved probe for the detection of SO derivatives through an off-on effect.

Analyst 2020 Jun 19. Epub 2020 Jun 19.

School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, PR China.

Herein we synthesize a DNA-sensitized Tb-MOF conjugate (DNA-Tb-MOF) as a time-resolved luminescent probe to sensitively and selectively assay SO2 and their derivatives (i.e., HSO3-) through a photoluminescence off-on effect. Read More

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http://dx.doi.org/10.1039/d0an00861cDOI Listing