Resonant dielectrophoresis and electrohydrodynamics for high-sensitivity impedance detection of whole-cell bacteria

In the space restricted airtight environment that people lives in, detecting harmful gas by miniature gas chromatography is the practical requirement at present, however, PIDs performance is key factor that restrict the application of miniature gas chromatography, the redesign of the detectors gas route in this paper aiming at improve detectors stability observably, and schemed out miniature PID with high sensitivity, low detection limit and fast response. The result of the experiment shows that the detection limit is 0.04ppm, the sensitivity is 101mv/ppm,the stability is 0.04×10-6/24h,meeting the project requirement. Keywords: photoionization detector; ionization chamber; sensitivity; detection limit;

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Construction of Two Stable Co(II)-Based Hydrogen-Bonded Organic Frameworks as a Luminescent Probe for Recognition of Fe3+ and Cr2O72− in H2O

Molecules ◽

10.3390/molecules26195955 ◽

2021 ◽

Vol 26 (19) ◽

pp. 5955

Author(s):

Qi-Ying Weng ◽

Ya-Li Zhao ◽

Jia-Ming Li ◽

Miao Ouyang

Keyword(s):

Detection Limit ◽

Aqueous Media ◽

Three Dimensional ◽

Cobalt Atom ◽

High Sensitivity ◽

X Ray Diffraction ◽

Chlorobenzoic Acid ◽

X Ray ◽

Highly Sensitive ◽

Hydrogen Bonded

A pair of cobalt(II)-based hydrogen-bonded organic frameworks (HOFs), [Co(pca)2(bmimb)]n (1) and [Co2(pca)4(bimb)2] (2), where Hpca = p-chlorobenzoic acid, bmimb = 1,3-bis((2-methylimidazol-1-yl)methyl)benzene, and bimb = 1,4-bis(imidazol-1-ylmethyl)benzene were hydrothermally synthesized and characterized through infrared spectroscopy (IR), elemental and thermal analysis (EA), power X-ray diffraction (PXRD), and single-crystal X-ray diffraction (SCXRD) analyses. X-ray diffraction structural analysis revealed that 1 has a one-dimensional (1D) infinite chain network through the deprotonated pca− monodentate chelation and with a μ2-bmimb bridge Co(II) atom, and 2 is a binuclear Co(II) complex construction with a pair of symmetry-related pca− and bimb ligands. For both 1 and 2, each cobalt atom has four coordinated twisted tetrahedral configurations with a N2O2 donor set. Then, 1 and 2 are further extended into three-dimensional (3D) or two-dimensional (2D) hydrogen-bonded organic frameworks through C–H···Cl interactions. Topologically, HOFs 1 and 2 can be simplified as a 4-connected qtz topology with a Schläfli symbol {64·82} and a 4-connected sql topology with a Schläfli symbol {44·62}, respectively. The fluorescent sensing application of 1 was investigated; 1 exhibits high sensitivity recognition for Fe3+ (Ksv: 10970 M−1 and detection limit: 19 μM) and Cr2O72− (Ksv: 12960 M−1 and detection limit: 20 μM). This work provides a feasible detection platform of HOFs for highly sensitive discrimination of Fe3+ and Cr2O72− in aqueous media.

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Rapid-Response, Low Detection Limit, and High-Sensitivity Capacitive Flexible Tactile Sensor Based on Three-Dimensional Porous Dielectric Layer for Wearable Electronic Skin

ACS Applied Materials & Interfaces ◽

10.1021/acsami.9b16511 ◽

2019 ◽

Vol 11 (43) ◽

pp. 40716-40725 ◽

Cited By ~ 19

Author(s):

Jie Qiu ◽

Xiaohui Guo ◽

Ran Chu ◽

Siliang Wang ◽

Wei Zeng ◽

...

Keyword(s):

Detection Limit ◽

Dielectric Layer ◽

Three Dimensional ◽

High Sensitivity ◽

Tactile Sensor ◽

Rapid Response ◽

Low Detection Limit ◽

Electronic Skin ◽

Wearable Electronic

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Marine Toxins Detection by Biosensors Based on Aptamers

Toxins ◽

10.3390/toxins12010001 ◽

2019 ◽

Vol 12 (1) ◽

pp. 1 ◽

Cited By ~ 3

Author(s):

Wei Ye ◽

Taomei Liu ◽

Weimin Zhang ◽

Muzi Zhu ◽

Zhaoming Liu ◽

...

Keyword(s):

Detection Limit ◽

Sensitivity And Specificity ◽

High Efficiency ◽

Rapid Development ◽

High Sensitivity ◽

Detection Methods ◽

Marine Toxins ◽

Time Saving ◽

Low Detection Limit ◽

The Future

Marine toxins cause great harm to human health through seafood, therefore, it is urgent to exploit new marine toxins detection methods with the merits of high sensitivity and specificity, low detection limit, convenience, and high efficiency. Aptasensors have emerged to replace classical detection methods for marine toxins detection. The rapid development of molecular biological approaches, sequencing technology, material science, electronics and chemical science boost the preparation and application of aptasensors. Taken together, the aptamer-based biosensors would be the best candidate for detection of the marine toxins with the merits of high sensitivity and specificity, convenience, time-saving, relatively low cost, extremely low detection limit, and high throughput, which have reduced the detection limit of marine toxins from nM to fM. This article reviews the detection of marine toxins by aptamer-based biosensors, as well as the selection approach for the systematic evolution of ligands by exponential enrichment (SELEX), the aptamer sequences. Moreover, the newest aptasensors and the future prospective are also discussed, which would provide thereotical basis for the future development of marine toxins detection by aptasensors.

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A comparative study of electrocatalytic oxidation of glucose on conductive Ni-MOF nanosheet arrays with different ligands

New Journal of Chemistry ◽

10.1039/d0nj04150e ◽

2020 ◽

Vol 44 (41) ◽

pp. 17849-17853

Author(s):

Yanxia Qiao ◽

Rui Zhang ◽

Fangyuan He ◽

Wenli Hu ◽

Xiaowei Cao ◽

...

Keyword(s):

Detection Limit ◽

Comparative Study ◽

Response Time ◽

Electrocatalytic Oxidation ◽

Glucose Sensor ◽

High Sensitivity ◽

Fast Response ◽

Serum Samples ◽

Nanosheet Arrays ◽

Oxidation Of Glucose

A glucose sensor based on conductive Ni-MOF nanosheet arrays/CC exhibits a fast response time, a low detection limit, a high sensitivity, and it can also be applied for the detection of glucose in human serum samples.

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Label-Free Split Aptamer Sensor for Femtomolar Detection of Dopamine by Means of Flexible Organic Electrochemical Transistors

Materials ◽

10.3390/ma13112577 ◽

2020 ◽

Vol 13 (11) ◽

pp. 2577 ◽

Cited By ~ 5

Author(s):

Yuanying Liang ◽

Ting Guo ◽

Lei Zhou ◽

Andreas Offenhäusser ◽

Dirk Mayer

Keyword(s):

Detection Limit ◽

Electrochemical Sensors ◽

Limit Of Detection ◽

High Sensitivity ◽

Label Free ◽

Dopamine Detection ◽

Electrochemical Transistor ◽

Sensitivity And Selectivity

The detection of chemical messenger molecules, such as neurotransmitters in nervous systems, demands high sensitivity to measure small variations, selectivity to eliminate interferences from analogues, and compliant devices to be minimally invasive to soft tissue. Here, an organic electrochemical transistor (OECT) embedded in a flexible polyimide substrate is utilized as transducer to realize a highly sensitive dopamine aptasensor. A split aptamer is tethered to a gold gate electrode and the analyte binding can be detected optionally either via an amperometric or a potentiometric transducer principle. The amperometric sensor can detect dopamine with a limit of detection of 1 μM, while the novel flexible OECT-based biosensor exhibits an ultralow detection limit down to the concentration of 0.5 fM, which is lower than all previously reported electrochemical sensors for dopamine detection. The low detection limit can be attributed to the intrinsic amplification properties of OECTs. Furthermore, a significant response to dopamine inputs among interfering analogues hallmarks the selective detection capabilities of this sensor. The high sensitivity and selectivity, as well as the flexible properties of the OECT-based aptasensor, are promising features for their integration in neuronal probes for the in vitro or in vivo detection of neurochemical signals.

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High sensitivity, homogeneous particle-based immunoassay for thyrotropin (Multipact).

Clinical Chemistry ◽

10.1093/clinchem/34.9.1745 ◽

1988 ◽

Vol 34 (9) ◽

pp. 1749-1752 ◽

Cited By ~ 11

Author(s):

T A Wilkins ◽

G Brouwers ◽

J C Mareschal ◽

C L Cambiaso

Keyword(s):

Detection Limit ◽

Present Method ◽

High Sensitivity ◽

Modular System ◽

Clinical Samples ◽

Good Precision ◽

Binding Properties ◽

Low Concentrations ◽

Homogeneous Particle ◽

Detection Technologies

Abstract We describe the first homogeneous, nonradioactive, high-sensitivity assay for human thyrotropin (TSH). The assay is based on particle immunoassay techniques, wherein 800-nm particles form the basis for the immunochemistry, delivery, and the detection technologies, respectively. Our assay also is the first to involve the use of fragmented monoclonal antibodies (to eliminate serum interferences) covalently coupled to particles without loss of their binding properties. Assays are performed in a semiautomated mode with use of a new modular system (Multipact). Equilibrium is reached in less than 2 h. Precision profile, sensitivity, and clinical studies indicate that the assay is accurate, has good precision at low concentrations, and that detection-limit characteristics compare well with those of a leading commercial high-sensitivity immunoradiometric assay (IRMA) for TSH. Dilution characteristics were satisfactory down to the assay's detection limit for a range of clinical samples. Correlation studies vs a reference IRMA method yielded the regression equation, present method = 0.976 (IRMA) + 0.002 milli-int. unit/L (r = 0.98), for 223 samples with TSH concentrations in the range 0 to 30 milli-int. units/L. For 40 samples with TSH less than or equal to 1.0 milli-int. unit/L it was: present method = 0.94 (IRMA) + 0.005 milli-int. unit/L (r = 0.96).

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A highly selective and sensitive fluorescent probe for lactate dehydrogenase based on ultrabright adenosine monophosphate capped gold nanoclusters

RSC Advances ◽

10.1039/c7ra00158d ◽

2017 ◽

Vol 7 (22) ◽

pp. 13438-13443 ◽

Cited By ~ 3

Author(s):

Jiao Liu ◽

Hong-Wei Li ◽

Yuqing Wu

Keyword(s):

Lactate Dehydrogenase ◽

Detection Limit ◽

Fluorescent Probe ◽

Fluorescence Probe ◽

Gold Nanoclusters ◽

High Sensitivity ◽

Adenosine Monophosphate ◽

Low Detection Limit ◽

Sensitivity And Selectivity

The ultrabright AuNCs@AMP are used as fluorescence probe to detect lactate dehydrogenase (LDH) with high sensitivity and selectivity, showing an extremely low detection limit of 0.2 nM (26 pg μL−1, 0.8 U L−1).

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