41,063 results match your criteria Analytical Chemistry[Journal]


Simultaneous Discrimination and Quantification of Enantiomeric Amino Acids under Physiological Conditions by Chiral F NMR Tag.

Anal Chem 2022 May 26. Epub 2022 May 26.

State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.

Enantiomeric analysis is of great significance in chemistry, chemical biology and pharmaceutical research. We herein propose a chiral F NMR tag containing an amino reactive NHS group to discriminate the enantiomeric amino acids under physiological conditions by NMR spectroscopy. The chiral F NMR tag readily forms stable amide products with the amino acids in aqueous solution. Read More

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Detection of Histidine-Tagged Protein in by Single-Cell Inductively Coupled Plasma-Mass Spectrometry.

Anal Chem 2022 May 26. Epub 2022 May 26.

Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo, Chiba 260-8675, Japan.

We have developed a rapid and precise quantification method for a histidine (His)-tagged recombinant protein produced in () by single-cell inductively coupled plasma-mass spectrometry (SC-ICP-MS). Plasmid vector containing enhanced green fluorescent protein (EGFP) or red fluorescent protein (mCherry) gene fused with His-tag was transformed into . The transformed was exposed to nickel (Ni) chloride or cobalt (Co) chloride for labeling His-tag with the Ni or Co ion. Read More

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Modulating the Fluorescence of Silver Nanoclusters Wrapped in DNA Hairpin Loops via Confined Strand Displacement and Transient Concatenate Ligation for Amplifiable Biosensing.

Anal Chem 2022 May 26. Epub 2022 May 26.

Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.

It is intriguing to modulate the fluorescence emission of DNA-scaffolded silver nanoclusters (AgNCs) via confined strand displacement and transient concatenate ligation for amplifiable biosensing of a DNA segment related to SARS-CoV-2 (DNA). Herein, three stem-loop structural hairpins for signaling, recognizing, and assisting are designed to assemble a variant three-way DNA device (3WDD) with the aid of two linkers, in which orange-emitting AgNC (AgNC) is stably clustered and populated in the closed loop of a hairpin reporter. The presence of DNA initiates the toehold-mediated strand displacement that is confined in this 3WDD for repeatable recycling amplification, outputting numerous hybrid DNA-duplex conformers that are implemented for a transient "head-tail-head" tandem ligation one by one. Read More

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Monitoring Protein Global and Local Parameters in Unfolding and Binding Studies: The Extended Applicability of the Diffusion Coefficient─Molecular Size Empirical Relations.

Anal Chem 2022 May 26. Epub 2022 May 26.

Institute of Chemistry, Analytical and BioNMR Laboratory, Eötvös Loránd University, Pázmány Péter sétány 1/a, Budapest 1117, Hungary.

Protein unfolding and denaturation are main issues in biochemical and pharmaceutical research. Using a global parameter, the translational diffusion coefficient , folded, unfolded, and intrinsically disordered proteins of a given molar mass can be distinguished based on their distinct hydrodynamic properties. For broader applications, we provide generalized, PFG-NMR-based empirical relations validated at different temperatures and ready to use with the corresponding corrections in different media. Read More

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Bio-Nanohybrid Cell Based Signal Amplification System for Electrochemical Sensing.

Anal Chem 2022 May 26. Epub 2022 May 26.

Biofuels Institute, School of Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China.

A signal amplification system for electrochemical sensing was established by bio-nanohybrid cells (BNC) based on bacterial self-assembly and biomineralization. The BNC was constructed by partially encapsulating a MR-1 cell with the self-biomineralized iron sulfide nanoparticles. The iron sulfide nanoparticle encapsulated BNCs showed high transmembrane electron transfer efficiency and was explored as a superior redox cycling module. Read More

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Two-Dimensional and Three-Dimensional Time-of-Flight Secondary Ion Mass Spectrometry Image Feature Extraction Using a Spatially Aware Convolutional Autoencoder.

Anal Chem 2022 May 26. Epub 2022 May 26.

Centre for Materials and Surface Science and Department of Chemistry and Physics, La Trobe University, Bundoora, Victoria 3086, Australia.

Feature extraction algorithms are an important class of unsupervised methods used to reduce data dimensionality. They have been applied extensively for time-of-flight secondary ion mass spectrometry (ToF-SIMS) imaging─commonly, matrix factorization (MF) techniques such as principal component analysis have been used. A limitation of MF is the assumption of linearity, which is generally not accurate for ToF-SIMS data. Read More

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Accurate and Efficient SIMS Oxygen Isotope Analysis of Composition-Variable Minerals: Online Matrix Effect Calibration for Dolomite.

Anal Chem 2022 May 26. Epub 2022 May 26.

Department of Mineralogy, Petrology and Applied Geology, Faculty of Earth Sciences, University of Barcelona, 08028 Barcelona, Spain.

High-quality oxygen isotope analysis of composition-variable minerals (e.g., ubiquitous carbonates) using secondary ion mass spectrometry (SIMS) is extremely challenging. Read More

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Smartphone-Based Electrochemiluminescence for Visual Simultaneous Detection of and Tumor Suppressor Gene Methylation in Thyroid Cancer Patient Plasma.

Anal Chem 2022 May 26. Epub 2022 May 26.

Biosensor Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, P.O. Box 1411713137, Islamic Republic of Iran.

Visual one-step simultaneous detection of low-abundance methylation is a crucial challenge in early cancer diagnosis in a simple manner. Through the design of a closed split bipolar electrochemistry system (BE), detection of promoter methylation of tumor suppressor genes in papillary thyroid cancer, and , was achieved using electrochemiluminescence. For this purpose, electrochemiluminescence of luminol loaded into the [email protected] and gold nanorod-functionalized graphite-like carbon nitride nanosheet ([email protected] NS), separately, on the anodic and cathodic pole bipolar electrodes (BPEs) in two different chambers of a bipolar cell were recorded on a smartphone camera. Read More

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Harmonized Quality Assurance/Quality Control Provisions for Nontargeted Measurement of Urinary Pesticide Biomarkers in the HBM4EU Multisite SPECIMEn Study.

Anal Chem 2022 May 26. Epub 2022 May 26.

Oniris, INRAE, LABERCA, Nantes 44300, France.

A set of quality assurance/quality control (QA/QC) criteria for nontargeted measurement of pesticide exposure markers in a large-scale study of human urine has been proposed and applied across five laboratories within the HBM4EU project. Quality control material, including reference standards and fortified pooled urine samples (QC urine) were prepared in a centralized way and distributed across participants to monitor analytical performance and consistency of the liquid chromatography coupled to high-resolution mass spectrometry data generated with a harmonized workflow. Signal intensities, mass accuracy, and retention times of selected QA/QC markers covering a broad range of physicochemical properties were monitored across QC solvent standards, QC urine samples, study urine samples, and procedural blanks, setting acceptance thresholds for repeatability and accuracy. Read More

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"RESET" Effect: Random Extending Sequences Enhance the Trans-Cleavage Activity of CRISPR/Cas12a.

Anal Chem 2022 May 26. Epub 2022 May 26.

State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Research Centre for Analytical Sciences, College of Chemistry, Nankai University, Tianjin 300071, People's Republic of China.

The trans-cleavage activity of CRISPR/Cas12a has been widely used in biosensing applications. However, the lack of exploration on the fundamental properties of CRISPR/Cas12a not only discourages further in-depth studies of the CRISPR/Cas12a system but also limits the design space of CRISPR/Cas12a-based applications. Herein, a "RESET" effect (random extending sequences enhance trans-cleavage activity) is discovered for the activation of CRISPR/Cas12a trans-cleavage activity. Read More

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Toward Nanomolar Multi-Component Analysis by F NMR.

Anal Chem 2022 May 25. Epub 2022 May 25.

Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China.

The widespread application of nuclear magnetic resonance (NMR) spectroscopy in detection is currently hampered by its inherently low sensitivity and complications resulting from the undesired signal overlap. Here, we report a detection scheme to address these challenges, where analytes are recognized by F-labeled probes to induce characteristic shifts of F resonances that can be used as "chromatographic" signatures to pin down each low-concentration analyte in complex mixtures. This unique signal transduction mechanism allows detection sensitivity to be enhanced by using massive chemically equivalent F atoms, which was achieved through the proper installation of nonafluoro--butoxy groups on probes of high structural symmetry. Read More

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Ultrasensitive and Single-Base Resolution Quantification of 8-Oxo-7,8-dihydroguanine in DNA by Extension and Ligation-Based qPCR.

Anal Chem 2022 May 25. Epub 2022 May 25.

Beijing National Laboratory for Molecular Sciences (BNLMS), MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.

Oxidative DNA damage is tightly linked to the development of multiple age-related diseases. The prominent oxidation product is 8-oxo-7,8-dihydroguanine (OG), which has been proved to be an important epigenetic-like biomarker. Quantification of the locus-specific OG frequency includes quantitative and locating information, which is of great significance for exploring the functional roles of OG in disease induction and gene regulation. Read More

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C-Isotope-Assisted Assessment of Metabolic Quenching During Sample Collection from Suspension Cell Cultures.

Anal Chem 2022 May 25. Epub 2022 May 25.

Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States.

Metabolomics and fluxomics are core approaches to directly profile and interrogate cellular metabolism in response to various genetic or environmental perturbations. In order to accurately measure the abundance and isotope enrichment of intracellular metabolites, cell culture samples must be rapidly harvested and cold quenched to preserve the in vivo metabolic state of the cells at the time of sample collection. When dealing with suspension cultures, this process is complicated by the need to separate the liquid culture media from cellular biomass prior to metabolite extraction. Read More

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Surpassing the Background Barrier for Multidimensional Single-Molecule Localization Super-Resolution Imaging: A Case of Lysosome-Exclusively Turn-on Probe.

Anal Chem 2022 May 25. Epub 2022 May 25.

State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China.

The background barrier restricts the dimensionality of live-cell single-molecule localization super-resolution imaging. Ideally, a probe exclusively turned on by its target, without any nonspecific fluorescence signals from off-target molecules, constitutes a practical solution to surpass this barrier. Yet, few such fluorophores have been developed. Read More

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Improved Peptide Backbone Fragmentation Is the Primary Advantage of MS-Cleavable Crosslinkers.

Anal Chem 2022 May 25. Epub 2022 May 25.

Technische Universität Berlin, Chair of Bioanalytics, 10623 Berlin, Germany.

Proteome-wide crosslinking mass spectrometry studies have coincided with the advent of mass spectrometry (MS)-cleavable crosslinkers that can reveal the individual masses of the two crosslinked peptides. However, recently, such studies have also been published with noncleavable crosslinkers, suggesting that MS-cleavability is not essential. We therefore examined in detail the advantages and disadvantages of using the commonly used MS-cleavable crosslinker, disuccinimidyl sulfoxide (DSSO). Read More

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Differentiation of Protonated Sulfonate Esters from Isomeric Sulfite Esters and Sulfones by Gas-Phase Ion-Molecule Reactions Followed by Diagnostic Collision-Activated Dissociation in Tandem Mass Spectrometry Experiments.

Anal Chem 2022 May 25. Epub 2022 May 25.

Department of Chemistry, Purdue University, 560 Oval Dr, West Lafayette, Indiana 47907, United States.

Sulfonate esters, a class of potentially mutagenic drug impurities, are strictly regulated in pharmaceuticals. On the other hand, sulfite esters and sulfones, analogs of sulfonate esters, have limited safety concerns. However, previously developed analytical methods for sulfonate ester identification cannot be used to differentiate sulfonate esters from the isomeric sulfite esters and sulfones. Read More

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Multiplexed Analysis of the Cellular Uptake of Polymeric Nanocarriers.

Anal Chem 2022 May 25. Epub 2022 May 25.

Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States.

Polymeric nanocarriers (PNCs) are versatile drug delivery vehicles capable of delivering a variety of therapeutics. Quantitatively monitoring their uptake in biological systems is essential for realizing their potential as next-generation delivery systems; however, existing quantification strategies are limited due to the challenges of detecting polymeric materials in complex biological samples. Here, we describe a metal-coded mass tagging approach that enables the multiplexed quantification of the PNC uptake in cells using mass spectrometry (MS). Read More

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Optical Microfiber with a Gold Nanorods-Black Phosphorous Nanointerface: An Ultrasensitive Biosensor and Nanotherapy Platform.

Anal Chem 2022 May 25. Epub 2022 May 25.

Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 511143, China.

The detection and therapy of cancers in the early stage significantly alleviate the associated dangers. Optical devices offer new opportunities for these early measures. However, the clinical translation of the existing methods is severely hindered by their relatively low sensitivity or unclear physiological metabolism. Read More

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Differentiation and Quantitation of Coeluting Isomeric Amadori and Heyns Peptides Using Sugar-Specific Fragment Ion Ratios.

Anal Chem 2022 May 24. Epub 2022 May 24.

Institute of Bioanalytical Chemistry, Faculty of Chemistry and Mineralogy, Universität Leipzig, 04103 Leipzig, Germany.

d-glucose and d-fructose present in blood, tissues, and organs of all mammals can react with amino groups, leading to glucated (Amadori) and fructated (Heyns) products, i.e., proteins glycated at lysine residues. Read More

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Disposable Microchamber with a Microfluidic Paper-Based Lid for Generation and Membrane Separation of SO Gas Employing an In Situ Electrochemical Gas Sensor for Quantifying Sulfite in Wine.

Anal Chem 2022 May 24. Epub 2022 May 24.

Flow Innovation-Research for Science and Technology Laboratories (Firstlabs), Mahidol University, Rama 6 Road, Bangkok 10400, Thailand.

This work presents a fully disposable microchamber for gas generation of a sample solution. The microchamber consists of a cylindrical well-reactor and a paper-based microfluidic lid (μFluidic lid), which also serves as the reagent loading and dispensing unit. The base of the reactor consists of a hydrophobic membrane covering an in-house graphene electrochemical gas sensor. Read More

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Accurate Prediction of y Ions in Beam-Type Collision-Induced Dissociation Using Deep Learning.

Anal Chem 2022 May 24. Epub 2022 May 24.

Bio Convergence Research Institute, Bertis Inc., Heungdeok 1-ro, Giheung-gu, Yongin-si, 16954 Gyeonggi-do, Republic of Korea.

Peptide fragmentation spectra contain critical information for the identification of peptides by mass spectrometry. In this study, we developed an algorithm that more accurately predicts the high-intensity peaks among the peptide spectra. The training data are composed of 180,833 peptides from the National Institute of Standards and Technology and Proteomics Identification database, which were fragmented by either quadrupole time-of-flight or triple-quadrupole collision-induced dissociation methods. Read More

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Electrochemical Impedimetric Real-Time Polymerase Chain Reactions Using Anomalous Charge Transfer Enhancement.

Anal Chem 2022 May 24. Epub 2022 May 24.

Graduate School of Engineering, Osaka University 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan.

We developed a new electrochemical impedimetric method for the real-time detection of polymerase chain reactions (PCR) based on our recent discovery that the DNA intercalator, [Ru(bpy)DPPZ], anomalously enhances charge transfer between redox mediators, K[Fe(CN)]/K[Fe(CN)], and a carbon electrode. Three mM [Fe(CN)] and 5 μM [Ru(bpy)DPPZ] were added to the PCR solution, and electrochemical impedance spectroscopy (EIS) measurements were performed at each elongation heat cycle. The charge transfer resistance (Rct) was initially low due to the presence of [Ru(bpy)DPPZ] in the solution. Read More

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Navigate Flying Molecular Elephants Safely to the Ground: Mass-Selective Soft Landing up to the Mega-Dalton Range by Electrospray Controlled Ion-Beam Deposition.

Anal Chem 2022 May 24. Epub 2022 May 24.

Physics Department E20, Technical University of Munich, 85748 Garching, Germany.

The prototype of a highly versatile and efficient preparative mass spectrometry system used for the deposition of molecules in ultrahigh vacuum (UHV) is presented, along with encouraging performance data obtained using four model species that are thermolabile or not sublimable. The test panel comprises two small organic compounds, a small and very large protein, and a large DNA species covering a 4-log mass range up to 1.7 MDa as part of a broad spectrum of analyte species evaluated to date. Read More

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Phenotypic Differentiation of Autotrophic and Heterotrophic Bacterial Cells Using Raman-DO Labeling.

Anal Chem 2022 May 24. Epub 2022 May 24.

Institute of Physical Chemistry and Abbe Center of Photonics (IPC), Friedrich-Schiller-University Jena, Helmholtzweg 4, 07743 Jena, Germany.

Carbon cycling is one of the major biogeochemical processes driven by bacteria. Autotrophic bacteria convert carbon dioxide (CO) into organic compounds that are used by heterotrophs. Mixotrophic bacteria can employ both autotrophy and heterotrophy for growth. Read More

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Separation of Americium from Curium through Oxidation State Control with Record Efficiency.

Anal Chem 2022 May 24. Epub 2022 May 24.

Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, P. R. China.

Separation of americium (Am) from curium (Cm) could greatly facilitate the development of advanced nuclear fuel cycles, help with accurate nuclear forensic analysis, and allow for more efficient recovery and utilization of the two strategic elements. In this work, an Am/Cm separation strategy based on the stabilization of pentavalent Am in a biphasic solvent extraction system using bismuthate as the oxidant and -tetraoctyl diglycolamide (TODGA) as the extractant was developed. The distinctive differences between Am(V) and Cm(III) in terms of both steric configuration and charge density afford record high Cm/Am separation factors (>10) through only one single contact in solvent extraction. Read More

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Dual-Engine Powered Paper Photoelectrochemical Platform Based on 3D DNA Nanomachine-Mediated CRISPR/Cas12a for Detection of Multiple miRNAs.

Anal Chem 2022 May 24. Epub 2022 May 24.

School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China.

This work proposed a novel double-engine powered paper photoelectrochemical (PEC) biosensor based on an anode-cathode cooperative amplification strategy and various signal enhancement mechanisms, which realized the monitoring of multiple miRNAs (such as miRNA-141 and miRNA-21). Specifically, CN quantum dots (QDs) sensitized ZnO nanostars and BiOI nanospheres simultaneously to construct a composite photoelectric layer that amplified the original photocurrent of the photoanode and photocathode, respectively. Through the independent design and partition of a flexible paper chip to functionalize injection holes and electrode areas, the bipolar combination completed the secondary upgrade of signals, which also provided biological reaction sites for multitarget detection. Read More

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Integrated Aptasensor Array for Sweat Drug Analysis.

Anal Chem 2022 May 24. Epub 2022 May 24.

College of Chemistry and Materials Science, Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Guangdong Engineering & Technology Research Centre of Graphene-like Materials and Products, Jinan University, Guangzhou 510632, China.

Drug abuse is seriously endangering human health and jeopardizing society. There is an urgent need for rapid, sensitive, portable, and easy-to-operate methods for the daily detection of drugs in biological matrices. However, current drug detection methods based on chromatography, spectroscopy, immunosorbent assays, etc. Read More

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Pressure-Enhanced Liquid Chromatography, a Proof of Concept: Tuning Selectivity with Pressure Changes and Gradients.

Anal Chem 2022 May 23. Epub 2022 May 23.

Waters Corporation, 34 Maple Street, Milford, Massachusetts 01757, United States.

Many chromatographers have observed that the operating pressure can dramatically change the chromatographic retention of solutes. Small molecules show observables changes, yet even more sizable effects are encountered with large biomolecules. With this work, we have explored the use of pressure as a method development parameter to alter the reversed-phase selectivity of peptide and protein separations. Read More

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Quantitative Evaluation on the Degradation Process of the Pulmonary Surfactant Monolayer When Exposed to Low-Level Ozone of Ambient Environment.

Anal Chem 2022 May 23. Epub 2022 May 23.

Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.

Ozone is a potent environmental oxidant with high chemical reactivity and is present in the ambient environment at a low level of a few tens of ppb. However, only limited information is known about low-level ozone's influence on the respiratory system. In the present study, we systematically investigated the degradation of 1-palmitoyl-2-oleoyl--glycero-3-phosphocholine (POPC), which is one of the major components of the pulmonary surfactant (PS), enabling breath function of the lung exposed to low ambient-level ozone (40 ± 10 ppb). Read More

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Generation and Screening of Antigen-Specific Nanobodies from Mammalian Cells Expressing the BCR Repertoire Library Using Droplet-Based Microfluidics.

Anal Chem 2022 May 23. Epub 2022 May 23.

BGI-Shenzhen, Shenzhen 518083, China.

Nanobodies, also known as VHHs, originate from the serum of Camelidae. Nanobodies have considerable advantages over conventional antibodies, including smaller size, more modifiable, and deeper tissue penetration, making them promising tools for immunotherapy and antibody-drug development. A high-throughput nanobody screening platform is critical to the rapid development of nanobodies. Read More

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