14,057 results match your criteria Analyst[Journal]


Instrumentational implementation for parallelized nanopore electrochemical measurements.

Analyst 2021 Jun 12. Epub 2021 Jun 12.

State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 210023, Nanjing, China.

Nanopore electrochemistry, as one of the promising tools for single molecule sensing, has proved its capability in DNA sequencing and protein analysis. To achieve a high resolution for obtaining molecular information, the nanopore electrochemical technique not only urgently requires an appropriate nanopore sensing interface with atomic resolution but also requires advanced instrumentation and its related data processing methods. In order to reveal the fundamental biological process and process the point-of-care diagnosis, it is necessary to use a nanopore sensing instrument with a high amperometric and temporal resolution as well as high throughput. Read More

View Article and Full-Text PDF

Ratiometric sensing of Zn with a new benzothiazole-based fluorescent sensor and living cell imaging.

Analyst 2021 Jun 11. Epub 2021 Jun 11.

School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China.

A new fluorescent probe, 3-(benzo[d]thiazol-2-yl)-5-bromosalicylaldehyde-4N-phenyl thiosemicarbazone (BTT), for ratiometric sensing of Zn2+ ions in methanol/HEPES buffer solution (3 : 2, pH = 7.4) is reported in this paper. The presence of Zn2+ ions yields a significant blue shift in the maximum emission of BTT from 570 nm to 488 nm, accompanied by a clear color change from orange to green. Read More

View Article and Full-Text PDF

A nucleus targetable fluorescent probe for ratiometric imaging of endogenous NO in living cells and zebrafishes.

Analyst 2021 Jun 10. Epub 2021 Jun 10.

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

Nitric oxide (NO) is an important cellular messenger molecule in the cardiovascular, nervous and immune systems. Real-time monitoring of NO activity in specific organelles of live cells is important to understand its biological function. In this work, a nucleus targetable ratiometric NO probe, Hoe-Rh-NO, is developed by linking Hoechst to rhodamine spirolactam. Read More

View Article and Full-Text PDF

Field induced displacement reactions with proton bound dimers of organophosphorus compounds in a tandem differential mobility spectrometer.

Analyst 2021 Jun 10. Epub 2021 Jun 10.

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

Endothermic displacement reactions between proton bound dimers of organophosphorus compounds (OPCs) and isopropanol (IPA) were enabled in air at ambient pressure with tandem differential mobility spectrometry (DMS). Proton bound dimers (M2H+) were mobility isolated in purified air with a first DMS stage, mixed with IPA at ≥100 ppm in a middle reactive stage at 106 to 160 Td from a symmetrical 4 MHz waveform, and mobility analyzed in a second DMS stage. Although the enthalpy for displacement of M by IPA in M2H+ is unfavorable by +44 to 50 kJ mol-1, formation of the heterogenous proton bound dimer, MH+(IPA) arises from field induced dissociation of M2H+ to MH+ and addition of IPA. Read More

View Article and Full-Text PDF

Padlock probe-based rolling circle amplification lateral flow assay for point-of-need nucleic acid detection.

Analyst 2021 Jun 9. Epub 2021 Jun 9.

School of Biomedical Engineering, Colorado State University, Fort Collins, CO 80523, USA. and Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA.

Sensitive, reliable and cost-effective detection of pathogens has wide ranging applications in clinical diagnostics and therapeutics, water and food safety, environmental monitoring, biosafety and epidemiology. Nucleic acid amplification tests (NAATs) such as PCR and isothermal amplification methods provide excellent analytical performance and significantly faster turnaround times than conventional culture-based methods. However, the inherent cost and complexity of NAATs limit their application in resource-limited settings and the developing world. Read More

View Article and Full-Text PDF

Live monitoring of cellular metabolism and mitochondrial respiration in 3D cell culture system using NMR spectroscopy.

Analyst 2021 Jun 9. Epub 2021 Jun 9.

Department of Biomedical Research and Radiology, University of Bern, Switzerland.

Background: Because of the interplay between mitochondrial respiration and cellular metabolism, the simultaneous monitoring of both cellular processes provides important insights for the understanding of biological processes. NMR flow systems provide a unique window into the metabolome of cultured cells. Simplified bioreactor construction based on commercially available flow systems increase the practicability and reproducibility of bioreactor studies using standard NMR spectrometers. Read More

View Article and Full-Text PDF

A new metric for relating macroscopic chromatograms to microscopic surface dynamics: the distribution function ratio (DFR).

Analyst 2021 Jun 9. Epub 2021 Jun 9.

Department of Chemistry, Rice University, Houston, Texas 77251, USA. and Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77251, USA and Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77251, USA and Smalley-Curl Institute, Rice University, Houston, Texas 77251, USA.

Heterogeneous stationary phase chemistry causes chromatographic tailing that lowers separation efficiency and complicates optimizing mobile phase conditions. Model-free metrics are attractive for assessing optimal separation conditions due to the low quantity of information required, but often do not reveal underlying mechanisms that cause tailing, for example, heterogeneous retention modes. We report a new metric, which we call the Distribution Function Ratio (DFR), based on a graphical comparison between the chromatogram and Gaussian cumulative distribution functions, achieving correspondence to ground truth surface dynamics with a single chromatogram. Read More

View Article and Full-Text PDF

Rapid isolation of extracellular vesicles from diverse biofluid matrices capillary-channeled polymer fiber solid-phase extraction micropipette tips.

Analyst 2021 Jun 9. Epub 2021 Jun 9.

Clemson University, Department of Chemistry, Clemson, SC 29634, USA.

Extracellular vesicles (EVs) play essential roles in biological systems based on their ability to carry genetic and protein cargos, intercede in cellular communication and serve as vectors in intercellular transport. As such, EVs are species of increasing focus from the points of view of fundamental biochemistry, clinical diagnostics, and therapeutics delivery. Of particular interest are 30-200 nm EVs called exosomes, which have demonstrated high potential for use in diagnostic and targeted delivery applications. Read More

View Article and Full-Text PDF

[email protected]: a magnetic polyaniline nanomaterial for highly efficient and handy enrichment of intact -glycopeptides.

Analyst 2021 Jun 8. Epub 2021 Jun 8.

Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine, Peking Union Medical College, 5 Dongdan San Tiao, Beijing 100005, China.

Glycosylation of proteins plays important roles in the occurrence and development of chronic diseases. In this study, we report an enrichment method of intact N-glycopeptides using a magnetic polyaniline nanomaterial ([email protected]). Under the synergistic effect of hydrogen bonding and electrostatic adsorption, [email protected] can rapidly and easily enrich N-glycopeptides derived from standard protein (bovine fetuin and transferrin) tryptic digests and serum haptoglobin tryptic digests. Read More

View Article and Full-Text PDF

Nitrogen and copper-doped carbon quantum dots with intrinsic peroxidase-like activity for double-signal detection of phenol.

Analyst 2021 Jun 9. Epub 2021 Jun 9.

Anhui Key Laboratory of Chemo-Biosensing, Key Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, P R China.

Herein, a simple and facile one-step hydrothermal carbonization synthesis procedure for the fabrication of N, Cu-doped carbon quantum dots (N, Cu-CQDs) as a peroxidase-mimicking enzyme was reported. The peroxidase-like performance of N, Cu-CQDs was assessed based on the oxidative coupling reaction of phenol with 4-aminoantipyrine (4-AAP) in the presence of hydrogen peroxide (H2O2). The N, Cu-CQDs/4-AAP/H2O2 system was applied to sensing phenol based on double signals of absorption spectra (or colorimetric visualization) as well as fluorescence spectra. Read More

View Article and Full-Text PDF

Large-scale investigation of single cell activities and response dynamics in a microarray chip with a microfluidics-fabricated microporous membrane.

Analyst 2021 Jun 9. Epub 2021 Jun 9.

Departments of Biomedical Engineering and Pathology, School of Basic Medical Science, Central South University, Changsha, Hunan 410013, China.

Microengineering technology involving microfabrication, micropatterning and microfluidics enables promising advances in single cell manipulation and analysis. Herein, we describe a parallel, large-scale, and temporal investigation of diverse single cell activities and response dynamics using a facile-assembled microwell array chip with a microfluidics-molded microporous membrane. We demonstrated that the versatility with respect to geometrical homogeneity and diversity of microporous membrane fabrication, as well as the stability, repeatability, and reproducibility rely on the well-improved molding. Read More

View Article and Full-Text PDF

Evolution of DNA aptamers against esophageal squamous cell carcinoma using cell-SELEX.

Analyst 2021 Jun 9. Epub 2021 Jun 9.

Department of Pathophysiology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China. and Henan Provincial Cooperative Innovation Center for Cancer Chemoprevention, Zhengzhou, Henan, China and State Key Laboratory of Esophageal Cancer Prevention and Treatment, Zhengzhou University, Zhengzhou, Henan, China and China-US Hormel (Henan) Cancer Institute, Zhengzhou, Henan, China and Cancer Chemoprevention International Collaboration Laboratory, Zhengzhou, Henan, China.

Esophageal cancer is the ninth most common cancer and the sixth most common cause of cancer-related death worldwide, and the esophageal squamous cell carcinoma (ESCC) subtype accounts for about 90% of all cases of esophageal cancer globally. Currently, ESCC is usually diagnosed in late stages, and targeted therapy is lacking. Therefore, the development of ESCC-specific recognition molecules for an early detection and targeted treatment of ESCC is urgently needed. Read More

View Article and Full-Text PDF

Detection and mapping of haemoglobin variants in blood fingermarks by MALDI MS for suspect "profiling".

Analyst 2021 Jun 9. Epub 2021 Jun 9.

Biomolecular Science Research Centre, Centre for Mass Spectrometry Imaging, Sheffield Hallam University, Sheffield, UK.

Over the past seven years Matrix Assisted Laser Desorption Ionisation Mass Spectrometry Profiling (MALDI MSP) and Imaging (MALDI MSI) have proven to be feasible tools for the detection of blood and its provenance in stains and fingermarks. However, whilst this capability as a confirmatory test addresses the primary questions at the scene of a violent crime, additional intelligence recoverable from blood can also prove important for investigations. A DNA profile is the most obvious and important example of such intelligence; however, it is not always suitable for identification purposes, depending on quantity, age and environmental conditions. Read More

View Article and Full-Text PDF

An electrochemiluminescence aptasensor for diethylstilbestrol assay based on resonance energy transfer between AgPO-Cu-MOF(II) and silver nanoparticles.

Analyst 2021 Jun 8. Epub 2021 Jun 8.

Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China. and Advanced Catalysis and Green Manufacturing Collaborative Innovation Center, Changzhou University, Changzhou 213164, China.

In this work, a novel electrochemiluminescence (ECL) aptasensor based on the resonance energy transfer (RET) effect between Ag3PO4-Cu-MOF (ii) and silver nanoparticles (Ag NPs) is proposed. The ECL emission spectra of Ag3PO4-Cu-MOF and the ultraviolet absorption spectra of Ag NPs showed a good spectral overlap. Based on this, we designed an "on-off-on" ECL sensing strategy for the sensitive and specific detection of diethylstilbestrol (DES). Read More

View Article and Full-Text PDF

Enhancing the enzymatic inhibition performance of Cu-based metal-organic frameworks by shortening the organic ligands.

Analyst 2021 Jun 7. Epub 2021 Jun 7.

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

Creating more exposed active sites on the metal-organic framework (MOF) surface is crucial for enhancing the recognition ability of MOF artificial receptors. Here, a copper-based MOF Cu(im)2 (im = imidazole) was utilized to act as an artificial receptor, inhibiting the activity of α-chymotrypsin. The shortest diazole ligand reduced the distance between regenerative copper sites, creating as many active sites as possible on the MOF unit surface. Read More

View Article and Full-Text PDF

Multiphoton imaging and Raman spectroscopy of the bovine vertebral endplate.

Analyst 2021 Jun 7. Epub 2021 Jun 7.

School of Physics and Astronomy, University of Exeter, Exeter, UK.

The interface between the intervertebral disc and the vertebral body is important to the discs' biomechanics and physiology, and is widely implicated in its pathology. This study aimed to explore biochemically and structurally the bony endplate, cartilage endplate and intervertebral disc, below the nucleus and below the annulus in healthy bovine tails. Multiphoton imaging and spontaneous Raman spectroscopy were employed. Read More

View Article and Full-Text PDF

Real-time monitoring of bead-based DNA hybridization in a microfluidic system: study of amplicon hybridization behavior on solid supports.

Analyst 2021 Jun 4. Epub 2021 Jun 4.

Centre de recherche en infectiologie de l'Université Laval, Axe Maladies infectieuses et immunitaires, Centre de recherche du CHU de Québec-Université Laval, 2705 boulevard Laurier, Québec, QC G1V 4G2, Canada. and Département de microbiologie-infectiologie et immunologie, Faculté de médecine, Université Laval, 1050 avenue de la Médecine, Québec, QC G1V 0A6, Canada.

DNA hybridization phenomena occurring on solid supports are not understood as clearly as aqueous phase hybridizations and mathematical models cannot predict some empirically obtained results. Ongoing research has identified important parameters but remains incomplete to accurately account for all interactions. It has previously been shown that the length of the overhanging (dangling) end of the target DNA strand following hybridization to the capture probe is correlated to interactions with the complementary strand in solution which can result in unbinding of the target and its release from the surface. Read More

View Article and Full-Text PDF

Correction: An electronic enzyme-linked immunosorbent assay platform for protein analysis based on magnetic beads and AlGaN/GaN high electron mobility transistors.

Analyst 2021 Jun 4. Epub 2021 Jun 4.

Key Laboratory of Multifunctional Nanomaterials and Smart Systems, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215125, People's Republic of China. and School of Nano Technology and Nano Bionics, University of Science and Technology of China, Hefei, 230026, People's Republic of China.

Correction for 'An electronic enzyme-linked immunosorbent assay platform for protein analysis based on magnetic beads and AlGaN/GaN high electron mobility transistors' by Jin Wang et al., Analyst, 2020, 145, 2725-2730, DOI: 10.1039/C9AN01809C. Read More

View Article and Full-Text PDF

Influence of oxygen plasma treatment on structural and spectral changes in silica-coated gold nanorods studied using total internal reflection microscopy and spectroscopy.

Analyst 2021 Jun 2. Epub 2021 Jun 2.

Energy Harvest-Storage Research Center (EHSRC), University of Ulsan, 93 Daehak-ro, Nam-gu, Ulsan 44610, Republic of Korea. and Department of Chemistry, University of Ulsan, 93 Daehak-ro, Nam-gu, Ulsan 44610, Republic of Korea.

This paper shows how oxygen plasma treatment affects the structural, localized surface plasmon resonance (LSPR) spectral, and spatial orientation changes in single gold nanorods coated with a mesoporous silica shell ([email protected]) in comparison with bare AuNRs with the same aspect ratio (AR). Single [email protected] subjected to different plasma treatment times were characterized using scanning electron microscopy and total internal reflection scattering (TIRS) microscopy and spectroscopy. The AR of the single AuNRs without a silica shell was decreased by structural deformation, while their LSPR linewidth was increased with increasing plasma treatment time. Read More

View Article and Full-Text PDF

Thermal equilibria between conformers enable highly reliable single-fluorophore ratiometric thermometers.

Analyst 2021 Jun 2. Epub 2021 Jun 2.

Fluorescence Research Group, Singapore University of Technology and Design, 8 Somapah Road, Singapore 487372.

Fluorescent thermometers based on organic dyes play an important role in the visualization of dynamic temperature topography with high resolution. Many molecular thermometers contain two fluorophores with different temperature responses to achieve ratiometric temperature detection. However, the stability and reliability of such ratiometric thermometers are highly dependent on the susceptibility of the fluorophores towards photobleaching. Read More

View Article and Full-Text PDF

Enzyme-responsive fluorescent nanoemulsion based on lipophilic dye liquid.

Analyst 2021 Jun 1. Epub 2021 Jun 1.

Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1-1 Gakuencho, Nakaku, Sakai, Osaka 599-8531, Japan.

An enzyme-responsive fluorescent nanoemulsion (NE) based on lipophilic dye liquid (LDL) was developed for alkaline phosphatase (ALP). The response mechanism of the NE involved enzymatic reactions and simultaneous extraction of anions. The LDL-based NE exhibited 3. Read More

View Article and Full-Text PDF

Plug-and-play assembly of paper-based colorimetric and electrochemical devices for multiplexed detection of metals.

Analyst 2021 Jun;146(11):3463-3473

Instituto de Química, Universidade Federal de Goiás, 74690-900, Goiânia, GO, Brazil. and Instituto Nacional de Ciência e Tecnologia de Bioanalítica, 13083-861, Campinas, SP, Brazil.

Heavy metals are the main pollutants present in aquatic environments and their presence in human organisms can lead to many different diseases. While many methods exist for analysis, colorimetric and electrochemistry are particularly attractive for on-site analysis and their integration on a single platform can improve multiplexed metals analysis. This report describes for the first time a "plug-and-play" (PnP) assembly for coupling a microfluidic paper-based device (μPAD) and a screen-printed electrochemical paper-based device (ePAD) using a vertical and reversible foldable mechanism for multiplexed detection of Fe, Ni, Cu, Zn, Cd and Pb in river water samples. Read More

View Article and Full-Text PDF

Electricity-free chemical heater for isothermal nucleic acid amplification with applications in COVID-19 home testing.

Analyst 2021 Jun 1. Epub 2021 Jun 1.

Mechanical Engineering and Applied Mechanics, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA 19104, USA.

Molecular detection of pathogenic nucleic acids from patient samples requires incubating biochemical reactions at specific temperatures to amplify DNA. This incubation is typically carried out with an electrical heater and a temperature controller. To reduce test cost, to eliminate the need for manufacturing incubators, which may require significant time, and to enable electricity-free operation, we use energetic compounds such as an Mg(Fe) alloy mixed with a phase-change material (PCM) that undergoes phase transformation at the desired incubation temperature. Read More

View Article and Full-Text PDF

Outstanding Reviewers for in 2020.

Authors:

Analyst 2021 Jun 2. Epub 2021 Jun 2.

View Article and Full-Text PDF

Microplasma-induced vapor generation for rapid, sample preparation-free screening of mercury in fruits and vegetables.

Analyst 2021 Jun 1. Epub 2021 Jun 1.

Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China.

A method for the rapid screening of toxic elements in fruits and vegetables is of significant importance to prevent human exposure to these elements. In this work, a simple method used for microplasma-induced vapor generation (μPIVG) was developed for the rapid screening and quantification of mercury in fruits and vegetables without sample preparation. A stainless-steel capillary was partly inserted into a juice droplet from the tested fruits and then the sample liquid automatically moved to the end of the capillary with the assistance of inherent capillary driving force. Read More

View Article and Full-Text PDF

TiN nanopillar-enhanced laser desorption and ionization of various analytes.

Analyst 2021 Jun;146(11):3454-3462

Toyota Central R&D Laboratories, Inc., Nagakute, Aichi 480-1192, Japan.

The present paper reports on the use of TiN nanopillars as a robust analytical substrate for laser desorption/ionization mass spectrometry (LDI-MS). TiN nanopillars were fabricated on silicon wafers through the dynamic oblique deposition of titanium, followed by thermal treatment in an ammonia atmosphere. The TiN nanopillars were readily applicable to a simple "dried-droplet" method in the LDI-MS without surface modification or pre-treatment. Read More

View Article and Full-Text PDF

Feature fusion of Raman chemical imaging and digital histopathology using machine learning for prostate cancer detection.

Analyst 2021 Jun 1. Epub 2021 Jun 1.

Technological University Dublin, School of Computer Science, City Campus, Grangegorman Lower, Dublin 7, Ireland. and Irish Centre for Applied AI and Machine Learning (CeADAR), Block 9/10, NexusUCD, Belfield Office Park, Clonskeagh, Dublin 4, Ireland.

The diagnosis of prostate cancer is challenging due to the heterogeneity of its presentations, leading to the over diagnosis and treatment of non-clinically important disease. Accurate diagnosis can directly benefit a patient's quality of life and prognosis. Towards addressing this issue, we present a learning model for the automatic identification of prostate cancer. Read More

View Article and Full-Text PDF

Label-free monitoring of crystalline chitin hydrolysis by chitinase based on Raman spectroscopy.

Analyst 2021 Jun 1. Epub 2021 Jun 1.

Department of Applied Physics, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan. and Advanced Photonics and Biosensing Open Innovation Laboratory, AIST-Osaka University, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan and Institute for Open and Transdisciplinary Research Initiatives, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.

We demonstrate a method for label-free monitoring of hydrolytic activity of crystalline-chitin-degrading enzyme, chitinase, by means of Raman spectroscopy. We found that crystalline chitin exhibited a characteristic Raman peak at 2995 cm-1, which did not appear in the reaction product, N,N'-diacetylchitobiose. We used this Raman peak as a marker of crystalline chitin degradation to monitor the hydrolytic activity of chitinase. Read More

View Article and Full-Text PDF

Commercially available rapid diagnostic tests for the detection of high priority pathogens: status and challenges.

Analyst 2021 Jun 1. Epub 2021 Jun 1.

Bioengineering Department, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs. Lyngby, Denmark.

The ongoing COVID-19 pandemic has shown the importance of having analytical devices that allow a simple, fast, and robust detection of pathogens which cause epidemics and pandemics. The information these devices can collect is crucial for health authorities to make effective decisions to contain the disease's advance. The World Health Organization published a list of primary pathogens that have raised concern as potential causes of future pandemics. Read More

View Article and Full-Text PDF

Glucose oxidase decorated fluorescent metal-organic frameworks as biomimetic cascade nanozymes for glucose detection through the inner filter effect.

Analyst 2021 May 31. Epub 2021 May 31.

Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China.

Metal-organic frameworks (MOFs) as a peroxidase mimic have been integrated with glucose oxidase (GOx) to achieve one-step glucose detection. However, limited by the loading amount of GOx, the performances of the developed glucose sensing assays still remain to be further improved to meet sensing requirements in diverse biological samples. Herein, with Fe3+ as the metal ion and 2-amino-benzenedicarboxylic acid as a ligand, a fluorescent Fe-based organic framework (NH2-MIL-101) with peroxidase-like activity was synthesized. Read More

View Article and Full-Text PDF