1,945 results match your criteria application label-free


M2aia-Interactive, fast, and memory-efficient analysis of 2D and 3D multi-modal mass spectrometry imaging data.

Gigascience 2021 Jul;10(7)

Faculty of Computer Science, Mannheim University of Applied Sciences, Paul-Wittsack-Straße 10, 68163 Mannheim, Germany.

Background: Mass spectrometry imaging (MSI) is a label-free analysis method for resolving bio-molecules or pharmaceuticals in the spatial domain. It offers unique perspectives for the examination of entire organs or other tissue specimens. Owing to increasing capabilities of modern MSI devices, the use of 3D and multi-modal MSI becomes feasible in routine applications-resulting in hundreds of gigabytes of data. Read More

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The application of label-free imaging technologies in transdermal research for deeper mechanism revealing.

Asian J Pharm Sci 2021 May 24;16(3):265-279. Epub 2020 Aug 24.

Institute of Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.

The penetration behavior of topical substances in the skin not only relates to the transdermal delivery efficiency but also involves the safety and therapeutic effect of topical products, such as sunscreen and hair growth products. Researchers have tried to illustrate the transdermal process with diversified theories and technologies. Directly observing the distribution of topical substances on skin by characteristic imaging is the most convincing approach. Read More

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Plumbagin can potently enhance the activity of xanthine oxidase: in vitro, in vivo and in silico studies.

BMC Pharmacol Toxicol 2021 Jul 17;22(1):45. Epub 2021 Jul 17.

Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou, 646000, Sichuan, China.

Background: Abnormally elevated xanthine oxidase (XO) activity has been verified to cause various pathological processes, such as gout, oxidative stress injury and metabolic syndrome. Thus, XO activators may exhibit above potential toxicological properties. Plumbagin (PLB) is an important active compound in traditional Chinese medicine (TCM), while its obvious toxic effects have been reported, including diarrhea, skin rashes and hepatic toxicity. Read More

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Correction to: The role of band structure in co- and Fe-co-doped BaSrZrYO perovskite semiconductor to design an electrochemical aptasensing platform: application in label-free detection of ochratoxin a using voltammetry.

Mikrochim Acta 2021 Jul 16;188(8):260. Epub 2021 Jul 16.

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Faculty of Physics and Electronic Science, Hubei University, Wuhan, 430062, Hubei, China.

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Effect of valproic acid on functional bleb morphology in a rabbit model of minimally invasive surgery.

Br J Ophthalmol 2021 Jul 15. Epub 2021 Jul 15.

Department of Ophthalmology, Singapore Eye Research Institute, Singapore.

Purpose: To determine the effect of valproic acid (VPA) on bleb morphology and scar characteristics in a rabbit model of minimally invasive glaucoma surgery (MIGS).

Methods: Nine New Zealand white rabbits were subjected to MIGS with intraoperative implantation of the PreserFlo MicroShunt. Rabbits were then administered with subconjunctival injections of phosphate buffered saline (PBS) (n=4) or with VPA (n=5). Read More

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Label-Free Fluorescent Aptasensor for Adenosine Triphosphate Detection Using SYBR Gold as a Probe.

Appl Spectrosc 2021 Jul 14:37028211028668. Epub 2021 Jul 14.

College of Agriculture, Yanbian University, Yanji, China.

In this experimental research, a label-free sensing strategy is developed and employed to detect adenosine triphosphate with utilization of aptamers, including exonuclease I and SYBR Gold. The conformation of aptamers bonding to the specific target molecule (ATP) is transformed into an antiparallel G-quadruplex structure from a random coil. Afterwards, considering the unfolded aptamers are the preferred substrates for exonuclease I, the addition of exonuclease I is used so as to digest unfolded aptamers in the mixture in a selective manner. Read More

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A label-free electrochemical platform based on a thionine functionalized magnetic Fe-N-C electrocatalyst for the detection of microRNA-21.

Analyst 2021 Jul 18;146(14):4557-4565. Epub 2021 Jun 18.

School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, PR China.

Taking a composite of a nanomaterial and a signal molecule as a substrate material can provide a label-free electrochemical platform. Besides, the nanomaterial with a high catalytic activity towards the signal molecule can improve the sensitivity of the platform. Herein, a thionine functionalized Fe-N-C nanocomposite was employed as the substrate. Read More

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Strategy to Synthesize Tunable Multiemission Carbon Dots and Their Multicolor Visualization Application.

ACS Appl Mater Interfaces 2021 Jul 12;13(28):33354-33362. Epub 2021 Jul 12.

Key Laboratory of Luminescence Analysis and Molecular Sensing, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, P. R. China.

Studies on multiemission fluorescent carbon dots (CDs) excited at one wavelength are extremely promising because of their label-free property, facile synthesis, multicolor visualization, and prevention of background interference. In this study, a novel template strategy to develop multiemission carbon dots (M-CDs) using fluorescent precursors has emerged. We attempted to elucidate the relationship between precursor substances and luminescence origins. Read More

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In vivo liquid biopsy for glioblastoma malignancy by the AFM and LSPR based sensing of exosomal CD44 and CD133 in a mouse model.

Biosens Bioelectron 2021 Jul 2;191:113476. Epub 2021 Jul 2.

Department of Neuroscience, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, SAR, China. Electronic address:

Glioblastoma (GBM) is the fatal brain tumor in which secreted lactate enhances the expression of cluster of differentiation 44 (CD44) and the release of exosomes, cell-derived nanovesicles (30-200 nm), and therefore promotes tumor malignant progression. This study found that lactate-driven upregulated CD44 in malignant Glioblastoma cells (GMs) enhanced the release of CD44-enriched exosomes which increased GMs' migration and endothelial cells' tube formation, and CD44 in the secreted exosomes was sensitively detected by "capture and sensing" Titanium Nitride (TiN) - Nanoholes (NH) - discs immunocapture (TIC) - atomic force microscopy (AFM) and ultrasensitive TiN-NH-localized surface plasmon resonance (LSPR) biosensors. The limit of detection for exosomal CD44 with TIC-AFM- and TiN-NH-LSPR-biosensors was 5. Read More

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Quantitative Proteome and Phosphoproteome Profiling in Magnaporthe oryzae.

Methods Mol Biol 2021 ;2356:109-119

Institute of Immunology, University Medical Center, Johannes-Gutenberg University Mainz, Mainz, Germany.

The quality and consistency in every sample preparation procedure is crucial for any scientific output. Therefore, it is of utmost importance to have easy, economic, and robust sample preparation protocols. Here, we describe a simple and robust bottom-up proteomic sample preparation strategy for identification and label-free quantification (LFQ) of proteins and phosphoproteins. Read More

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January 2021

High spatiotemporal resolution optoacoustic sensing with photothermally induced acoustic vibrations in optical fibres.

Nat Commun 2021 07 6;12(1):4139. Epub 2021 Jul 6.

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

Optoacoustic vibrations in optical fibres have enabled spatially resolved sensing, but the weak electrostrictive force hinders their application. Here, we introduce photothermally induced acoustic vibrations (PTAVs) to realize high-performance fibre-based optoacoustic sensing. Strong acoustic vibrations with a wide range of axial wavenumbers k are photothermally actuated by using a focused pulsed laser. Read More

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[Affinity chromatography based phosphoproteome research on lung cancer cells and its application].

Se Pu 2021 Jan;39(1):77-86

State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.

Phosphorylation is one of the most important post-translational modifications in proteins. It plays a key role in numerous cellular processes, including signal transduction, cell proliferation, and intercellular communication. More than 30% of the cellular proteins are phosphorylated at a given time. Read More

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January 2021

Printing Microbial Dark Matter: Using Single Cell Dispensing and Genomics to Investigate the Patescibacteria/Candidate Phyla Radiation.

Front Microbiol 2021 16;12:635506. Epub 2021 Jun 16.

Institute for Biological Interfaces 5, Karlsruhe Institute of Technology, Karlsruhe, Germany.

As of today, the majority of environmental microorganisms remain uncultured. They are therefore referred to as "microbial dark matter." In the recent past, cultivation-independent methods like single-cell genomics (SCG) enabled the discovery of many previously unknown microorganisms, among them the Patescibacteria/Candidate Phyla Radiation (CPR). Read More

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Biofilm inhibition by biocompatible poly(ε-caprolactone) nanocapsules loaded with essential oils and their cyto/genotoxicity to human keratinocyte cell line.

Int J Pharm 2021 Jul 1;606:120846. Epub 2021 Jul 1.

Istituto Chimica Biomolecolare - Consiglio Nazionale delle Ricerche, Via Paolo Gaifami 18, 95126 Catania, Italy. Electronic address:

Essential oils (EOs) of Thymus capitatus (Th) carvacrol chemotype and Origanum vulgare (Or) thymol and carvacrol chemotype were encapsulated in biocompatible poly(ε-caprolactone) nanocapsules (NCs). These nanosystems exhibited antibacterial, antifungal, and antibiofilm activities against Staphylococcus aureus, Escherichia coli, and Candida albicans. Th-NCs and Or-NCs were more effective against all tested strains than pure EOs and at the same time were not cytotoxic on HaCaT (T0020001) human keratinocyte cell line. Read More

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Nitrogen-doped carbon quantum dots fabricated from cellulolytic enzyme lignin and its application to the determination of cytochrome c and trypsin.

Anal Bioanal Chem 2021 Jul 1. Epub 2021 Jul 1.

College of Chemistry, Chemical Engineering and Resource Utilization, Key Laboratory of Forest Plant Ecology, Northeast Forestry University, 26 Hexing Road, Harbin, 150040, Heilongjiang, China.

A sensitive and effective strategy for the detection of cytochrome c (Cyt c) and trypsin was developed using biomass nitrogen-doped carbon quantum dots (N-CQDs) as the fluorescence probe. N-CQDs were synthesized through a one-pot hydrothermal method by utilizing cellulolytic enzyme lignin as the carbon source and ammonia as the solvent and nitrogen source. The obtained N-CQDs had good water solubility and stable optical properties. Read More

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Engineering a Rolling-Circle Strand Displacement Amplification Mediated Label-Free Ultrasensitive Electrochemical Biosensing Platform.

Anal Chem 2021 07 1;93(27):9568-9574. Epub 2021 Jul 1.

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

In this work, an original rolling-circle strand displacement amplification (RC-SDA) was developed by introducing a circle DNA with two recognition domains as a template instead of the limited liner DNA template in traditional strand displacement amplification (SDA), which displayed much shorter reaction time down to 30 min and quite higher conversion efficiency of more than 1.77 × 10 compared with those of traditional strand displacement amplification (SDA) and could be applied to construct a label-free biosensor for ultrasensitive detection of an HIV DNA fragment. Once the target HIV DNA fragment interacts with the template circle DNA, the RC-SDA could be activated to dramatically output amounts of mimic target DNA with the assistance of the Phi29 DNA polymerase and Nb. Read More

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Microfluidic Tools for Enhanced Characterization of Therapeutic Stem Cells and Prediction of Their Potential Antimicrobial Secretome.

Antibiotics (Basel) 2021 Jun 22;10(7). Epub 2021 Jun 22.

Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, 40126 Bologna, Italy.

Antibiotic resistance is creating enormous attention on the development of new antibiotic-free therapy strategies for bacterial diseases. Mesenchymal stromal stem cells (MSCs) are the most promising candidates in current clinical trials and included in several cell-therapy protocols. Together with the well-known immunomodulatory and regenerative potential of the MSC secretome, these cells have shown direct and indirect anti-bacterial effects. Read More

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Analysing Complex Oral Protein Samples: Complete Workflow and Case Analysis of Salivary Pellicles.

J Clin Med 2021 Jun 25;10(13). Epub 2021 Jun 25.

Faculty of Dentistry, The University of Hong Kong, Hong Kong, China.

Studies on small quantity, highly complex protein samples, such as salivary pellicle, have been enabled by recent major technological and analytical breakthroughs. Advances in mass spectrometry-based computational proteomics such as Multidimensional Protein Identification Technology have allowed precise identification and quantification of complex protein samples on a proteome-wide scale, which has enabled the determination of corresponding genes and cellular functions at the protein level. The latter was achieved via protein-protein interaction mapping with Gene Ontology annotation. Read More

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Sheath-assisted versus sheathless dielectrophoretic particle separation.

Electrophoresis 2021 Jul 1. Epub 2021 Jul 1.

School of Engineering, Faculty of Applied Science, The University of British Columbia, Kelowna, BC, Canada.

Lab-on-chip devices are widely being used for binary and ternary cell/particle separation applications. Among the lab-on-chip methods, dielectrophoresis (DEP) is a cost-effective and label-free method, with great capabilities for size-based separation of cells and particles, which is mostly performed in sheath-assisted forms. However, the elimination of the sheath flows offers advantages such as ease of operation and higher sample throughput. Read More

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Biomass carbon dots derived from for the direct detection of glutathione and their imaging application in living cells.

J Mater Chem B 2021 Jul;9(28):5670-5681

Guangdong Provincial Key laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China.

The development of long-wavelength emission carbon dots as a label-free sensing platform for the direct detection of glutathione (GSH) is still of great challenge. Herein, novel rose-red fluorescence carbon dots (wCDs) with a long-wavelength emission of 654 nm were successfully synthesized by a one-step microwave-solvothermal treatment of biomass Wedelia trilobata. The biomass-based wCDs could sensitively respond to copper ions (Cu2+) with a limit of detection (LOD) of 0. Read More

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Highly selective and sensitive sandwich immunosensor platform modified with MUA-capped GNPs for detection of spike Receptor Binding Domain protein: A precious marker of COVID 19 infection.

Sens Actuators B Chem 2021 Oct 24;345:130355. Epub 2021 Jun 24.

Çanakkale Onsekiz Mart University, Faculty of Engineering, Bioengineering Department, Çanakkale, Turkey.

A label-free electrochemical biosensing system as a suitable analysis technique for COVID 19 specific spike receptor-binding domain protein (RBD) was developed with an aim to facilitate the diagnosis of coronavirus. A novel production procedure for the fabrication of gold nanoparticles (GNPs)-capped 11-mercaptoundecanoic acid (MUA) modified bioelectrode was presented and its application potential for RBD biosensing was examined. The bioelectrode fabrication protocol was based on covalent ester linking formation between hydroxylated ITO electrode and GNPs-capped MUA () with carboxyl ends. Read More

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October 2021

Label-free breast cancer detection using fiber probe-based Raman spectrochemical biomarker-dominated profiles extracted from a mixture analysis algorithm.

Anal Methods 2021 Jun 29. Epub 2021 Jun 29.

Department of Biomedical Engineering, College of Medicine, Kyung Hee University, Seoul, 02447, South Korea.

We report the development of a label-free, simple, and high efficiency breast cancer detection platform with multimodal biomarker analytic algorithms on a portable 785 nm Raman setup with an endoscopic Raman-lensed fiber optic probe. We propose a multimodal biomarker extraction algorithm (PCMA) implemented by combining a multivariate statistics principal component analysis (PCA) algorithm and a multivariate curve resolution-alternating least squares (MCR-ALS) computational model for extraction of the biomarker information hidden in Raman spectrochemical data. We show that the six Raman spectrochemical peaks at 1009, 1270, 1305/1443, 1658, and 1750 cm-1 assigned to phenylalanine, amide III in proteins, CH2 deformation in lipids, amide I in proteins, and carbonyl, respectively, can be used as a biomarker for breast cancer diagnosis using the biomarker-dominated PCMA spectrochemical spectra of breast tissues. Read More

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A novel liquid crystal-based aptasensor for ultra-low detection of ochratoxin a using a π-shaped DNA structure: Promising for future on-site detection test strips.

Biosens Bioelectron 2021 Jun 20;191:113457. Epub 2021 Jun 20.

Department of Food Safety and Quality Control, Research Institute of Food Science and Technology (RIFST), Mashhad, Iran.

Ochratoxin A (OTA) as the most dangerous mycotoxin is produced by Aspergillus Ochraceus and Penicillium verrucosum. OTA can be found in beverages and foodstuffs that induces the teratogenic, nephrotoxic, carcinogenic, and immunosuppressive effects on humans. Hence, developing highly sensitive methods for its detection is of great importance. Read More

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Boron nitride nanosheet modified label-free electrochemical immunosensor for cancer antigen 125 detection.

Biosens Bioelectron 2021 Jun 18;191:113454. Epub 2021 Jun 18.

Adnan Menderes University, Faculty of Science and Arts, Department of Chemistry, Aydın, Turkey; Adnan Menderes University, Nanotechnology Application and Research Center, Aydın, Turkey. Electronic address:

In this presented study, a new boron nitride nanosheets modified label-free electrochemical immunosensors were prepared for early detection of cancer antigen 125 (CA125). To aim for, boron nitride (BN) nanosheets were synthesized by conventional sonication-assisted method and then characterized. BN nanosheets were used for the surface modification of the working electrode of the screen-printed electrode (SPE). Read More

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Construction of Peroxidase-like Metal-Organic Frameworks in TiO Nanochannels: Robust Free-Standing Membranes for Diverse Target Sensing.

Anal Chem 2021 07 25;93(27):9486-9494. Epub 2021 Jun 25.

College of Sciences, Northeastern University, Shenyang 110004, China.

The high cost and easy denaturation of natural enzymes under environmental conditions hinder their practical usefulness in sensing devices. In this study, peroxidase (POD)-like metal-organic frameworks (MOFs) were grown in the nanochannels of an anodized TiO membrane (TiONM) as an electrochemical platform for multitarget sensing. By directly using a nanochannel wall as the precursor of metal nodes, Ti-MOFs were derived on the nanochannel wall. Read More

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Self-assembled nano-Ag/[email protected] film composite SERS substrates show high uniformity and high enhancement factor for creatinine detection.

Nanotechnology 2021 Jul 9;32(39). Epub 2021 Jul 9.

College of Optoelectronic Engineering, Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, People's Republic of China.

Serum creatinine is a key biomarker for the diagnosis and monitoring of kidney disease. Rapid and sensitive creatinine detection is thus important. Here, we propose a high-performance nano-Ag/[email protected] film composite SERS substrate for the rapid detection of creatinine in human serum. Read More

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Label-free imaging of human brain tissue at subcellular resolution for potential rapid intra-operative assessment of glioma surgery.

Theranostics 2021 24;11(15):7222-7234. Epub 2021 May 24.

Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.

Frozen section and smear preparation are the current standard for intraoperative histopathology during cancer surgery. However, these methods are time-consuming and subject to limited sampling. Multiphoton microscopy (MPM) is a high-resolution non-destructive imaging technique capable of optical sectioning in real time with subcellular resolution. Read More

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In-Cell Nanoelectronics: Opening the Door to Intracellular Electrophysiology.

Nanomicro Lett 2021 May 15;13(1):127. Epub 2021 May 15.

State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-Sen University, Guangzhou, 510006, People's Republic of China.

Establishing a reliable electrophysiological recording platform is crucial for cardiology and neuroscience research. Noninvasive and label-free planar multitransistors and multielectrode arrays are conducive to perform the large-scale cellular electrical activity recordings, but the signal attenuation limits these extracellular devices to record subthreshold activities. In recent decade, in-cell nanoelectronics have been rapidly developed to open the door to intracellular electrophysiology. Read More

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Scattering oblique plane microscopy for blood cell imaging.

Biomed Opt Express 2021 May 5;12(5):2575-2585. Epub 2021 Apr 5.

Department of Biomedical Engineering, Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.

Oblique plane microscopy (OPM) enables high speed, volumetric fluorescence imaging through a single-objective geometry. While these advantages have positioned OPM as a valuable tool to probe biological questions in animal models, its potential for human imaging is largely unexplored due to its typical use with exogenous fluorescent dyes. Here we introduce a scattering-contrast oblique plane microscope (sOPM) and demonstrate label-free imaging of blood cells flowing through human capillaries . Read More

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TiCT MXene sensor for rapid Hg analysis in high salinity environment.

J Hazard Mater 2021 Jun 2;418:126301. Epub 2021 Jun 2.

College of Environmental Science and Engineering, Biomedical Multidisciplinary Innovation Research Institute, Shanghai East Hospital, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China. Electronic address:

Mercury is one of the leading chemicals of concern and receives much attention in environmental safety. It is of great necessity to develop advanced Hg analysis method for rapid detection and monitoring. Field-effect transistor (FET) sensor, an emerging electronic sensor, has received great attention in environmental analysis since it has unique advantages in achieving rapid analysis of chemicals. Read More

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