A colorimetric nitrite detection system with excellent selectivity and high sensitivity based on Ag@Au nanoparticles

The Analyst ◽  
2015 ◽  
Vol 140 (4) ◽  
pp. 1076-1081 ◽  
Author(s):  
Tianhua Li ◽  
Yonglong Li ◽  
Yujie Zhang ◽  
Chen Dong ◽  
Zheyu Shen ◽  
...  
Keyword(s):  
Au Nanoparticles ◽  
Color Change ◽  
Detection System ◽  
High Sensitivity ◽  
Nitrite Detection ◽  
Excellent Selectivity

NO2− could be directly detected with high sensitivity and excellent selectivity by visualizing the color change of a dispersion of Ag@AuNPs with the unaided eye.

scholarly journals Interfacing aptamers, nanoparticles and graphene in a hierarchical structure for highly selective detection of biomolecules in OECT devices

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Carlotta Peruzzi ◽  
Silvia Battistoni ◽  
Daniela Montesarchio ◽  
Matteo Cocuzza ◽  
Simone Luigi Marasso ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Au Nanoparticles ◽  
Limit Of Detection ◽  
High Sensitivity ◽  
Minimal Invasiveness ◽  
Hierarchic Structure ◽  
Final Response ◽  
Detection Of Biomolecules ◽  
Good Signal ◽  
Detection Of Biomarkers

AbstractIn several biomedical applications, the detection of biomarkers demands high sensitivity, selectivity and easy-to-use devices. Organic electrochemical transistors (OECTs) represent a promising class of devices combining a minimal invasiveness and good signal transduction. However, OECTs lack of intrinsic selectivity that should be implemented by specific approaches to make them well suitable for biomedical applications. Here, we report on a biosensor in which selectivity and a high sensitivity are achieved by interfacing, in an OECT architecture, a novel gate electrode based on aptamers, Au nanoparticles and graphene hierarchically organized to optimize the final response. The fabricated biosensor performs state of the art limit of detection monitoring biomolecules, such as thrombin-with a limit of detection in the picomolar range (≤ 5 pM) and a very good selectivity even in presence of supraphysiological concentrations of Bovine Serum Albumin (BSA-1mM). These accomplishments are the final result of the gate hierarchic structure that reduces sterich indrance that could contrast the recognition events and minimizes false positive, because of the low affinity of graphene towards the physiological environment. Since our approach can be easily applied to a large variety of different biomarkers, we envisage a relevant potential for a large series of different biomedical applications.

Abstract 4336: Interrogating the Human Myocardial Interstitium during Myocardial Arrest and Reperfusion: Dynamic Changes in Cytokines and Protease Activity

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Robert E Stroud ◽  
Christine N Koval ◽  
Isabelle Gengler ◽  
Anne M Deschamps ◽  
John S Ikonomidis ◽  
...  
Keyword(s):  
Detection System ◽  
Ischemia Reperfusion ◽  
Dynamic Assessment ◽  
High Sensitivity ◽  
Fluorescent Detection ◽  
Suspension Array ◽  
Cytokine Analysis ◽  
And Function ◽  
Inflammatory Molecules ◽  
Pulmonary Bypass

Background. Cytokines, such as the interleukins (IL1β, IL2, IL6) and tumor necrosis factor (TNF) can modulate myocardial structure and function with ischemia/reperfusion (I/R) but dynamic assessment of these biological molecules within the human myocardial interstitium with I/R has not been performed, and the inter-relationship to matrix metalloproteinases activity (MMPact) remains unexplored. Accordingly, a fluorogenic microdialysis method was used to simultaneously measure myocardial interstitial cytokine levels and MMPact in patients during and following I/R. Methods . MMPact was measured in patients (n=13) undergoing cardio-pulmonary bypass (CPB) at baseline, during myocardial arrest and CPB (on-CPB), and immediately following reperfusion and separation from CPB (post-CPB) by a validated in-line microdialysis fluorescent detection system. Myocardial interstitial fluid was subjected to cytokine analysis by high sensitivity multiplex suspension array. Results . Interstitial MMPact increased by over 30% post-CPB and was accompanied by a specific change in cytokine profiles (Figure ). The classical pro-inflammatory molecules such as TNF and IL6 were either not detectable or unchanged, whereas IL1β and IL2 which can be proinflammatory, were increased. Conclusions. These unique results demonstrated that a dynamic cytokine signature occurs within the human myocardial interstitium following I/R and is temporally related to heightened MMP activity. Direct interrogation of the human myocardial interstitium may provide a unique insight into critical signaling pathways which may evoke adverse structural and functional events following I/R.

Compact Detection System for High Sensitivity Hydrogen Profiling of Materials by Nuclear Reaction Analysis

2009 ◽  
Author(s):  
Daniel Keith Marble ◽  
Ben Urban ◽  
Jose Pacheco ◽  
Floyd D. McDaniel ◽  
Barney L. Doyle
Keyword(s):  
Nuclear Reaction ◽  
Detection System ◽  
High Sensitivity ◽  
Nuclear Reaction Analysis

scholarly journals Prototype Sistem Deteksi Partial Discharge Pada Isolasi Kabel Menggunakan Sensor Microphone (Prototype Of Partial Discharge Detection System In Cable Isolation Using Microphone Sensor)

2019 ◽  
Vol 3 (2) ◽  
pp. 206
Author(s):  
Mochamad Zaeynuri Setiawan ◽  
Fachrudin Hunaini ◽  
Mohamad Mukhsim
Keyword(s):  
Detection System ◽  
Partial Discharge ◽  
Measurement Data ◽  
Negative Ions ◽  
High Sensitivity ◽  
Sound Waves ◽  
Cable Insulation ◽  
Insulation Failure ◽  
Measurement Results ◽  
Discharge Detection

The phenomenon that often arises in a substation is the problem of partial discharge in outgoing cable insulation. Partial discharge is a jump of positive and negative ions that are not supposed to meet so that it can cause a spark jump. If a partial discharge is left too long it can cause insulation failure, the sound of snakes like hissing and the most can cause a flashover on the outgoing cable. Then a partial discharge detection prototype was made in the cable insulation in order to anticipate the isolation interference in the outgoing cable. Can simplify the work of substation operators to check the reliability of insulation on the outgoing side of each cubicle. So it was compiled as a method for measuring sound waves caused by partial discharge in the process of measuring using a microphone sensor, the Arduino Mega 2560 module as a microcontroller, the LCD TFT as a monitoring and the MicroSD card module as its storage. The microphone sensor is a sensor that has a high sensitivity to sound, has 2 analog and digital readings, and is easily designed with a microcontroller. Basically the unit of measure measured at partial discharge is Decibels. The results of the prototype can be applied to the cubicle and the way it works is to match the prototype to the outgoing cubicle cable then measure from the cable boots connector to the bottom of the outgoing cable with a distance of 1 meter. Then the measurement results will be monitored on the TFT LCD screen in the form of measurement results, graphs and categories on partial discharge. In this design the measurement data made by the microphone can be stored with microSD so that it can make an evaluation of partial discharge handling in outgoing cable insulation.

scholarly journals Scanning single-molecule counting system for Eprobe with highly simple and effective approach

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243319
Author(s):  
Takeshi Hanami ◽  
Tetsuya Tanabe ◽  
Takuya Hanashi ◽  
Mitsushiro Yamaguchi ◽  
Hidetaka Nakata ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Single Molecule ◽  
Detection System ◽  
Signal To Noise Ratio ◽  
High Sensitivity ◽  
Nucleic Acid Detection ◽  
Digital Measurement ◽  
Excitation Light ◽  
Target Nucleic Acid ◽  
Fluorescent Molecules

Here, we report a rapid and ultra-sensitive detection technique for fluorescent molecules called scanning single molecular counting (SSMC). The method uses a fluorescence-based digital measurement system to count single molecules in a solution. In this technique, noise is reduced by conforming the signal shape to the intensity distribution of the excitation light via a circular scan of the confocal region. This simple technique allows the fluorescent molecules to freely diffuse into the solution through the confocal region and be counted one by one and does not require statistical analysis. Using this technique, 28 to 62 aM fluorescent dye was detected through measurement for 600 s. Furthermore, we achieved a good signal-to-noise ratio (S/N = 2326) under the condition of 100 pM target nucleic acid by only mixing a hybridization-sensitive fluorescent probe, called Eprobe, into the target oligonucleotide solution. Combination of SSMC and Eprobe provides a simple, rapid, amplification-free, and high-sensitive target nucleic acid detection system. This method is promising for future applications to detect particularly difficult to design primers for amplification as miRNAs and other short oligo nucleotide biomarkers by only hybridization with high sensitivity.

scholarly journals Electrochemistry/Photoelectrochemistry-Based Immunosensing and Aptasensing of Carcinoembryonic Antigen

Sensors ◽  
2021 ◽  
Vol 21 (22) ◽  
pp. 7742
Author(s):  
Jingjing Jiang ◽  
Jili Xia ◽  
Yang Zang ◽  
Guowang Diao
Keyword(s):  
Carcinoembryonic Antigen ◽  
Early Cancer ◽  
Low Cost ◽  
High Sensitivity ◽  
Advanced Materials ◽  
Current Trends ◽  
Signaling Strategies ◽  
Development Prospects ◽  
Screening And Diagnosis ◽  
Excellent Selectivity

Recently, electrochemistry- and photoelectrochemistry-based biosensors have been regarded as powerful tools for trace monitoring of carcinoembryonic antigen (CEA) due to the fact of their intrinsic advantages (e.g., high sensitivity, excellent selectivity, small background, and low cost), which play an important role in early cancer screening and diagnosis and benefit people’s increasing demands for medical and health services. Thus, this mini-review will introduce the current trends in electrochemical and photoelectrochemical biosensors for CEA assay and classify them into two main categories according to the interactions between target and biorecognition elements: immunosensors and aptasensors. Some recent illustrative examples are summarized for interested readers, accompanied by simple descriptions of the related signaling strategies, advanced materials, and detection modes. Finally, the development prospects and challenges of future electrochemical and photoelectrochemical biosensors are considered.

Easy-to-Fabricate K2Pd(SO3)2-Dyed Polyester Fabric with Highly Selective and Fast Response to Carbon Monoxide

2021 ◽  
Vol 21 (8) ◽  
pp. 4400-4405
Author(s):  
Junyeop Lee ◽  
Nam Gon Do ◽  
Dong Hyuk Jeong ◽  
Sae-Wan Kim ◽  
Maeum Han ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Color Change ◽  
High Sensitivity ◽  
Cost Effective ◽  
Fast Response ◽  
Polyester Fabric ◽  
High Porosity ◽  
Sensing Material ◽  
Sensitivity And Selectivity ◽  
And Performance

Carbon monoxide (CO) is an odorless, colorless, tasteless, extremely flammable, and highly toxic gas. It is produced when there is insufficient oxygen supply during the combustion of carbon to produce carbon dioxide (CO2). CO is produced from operating engines, stoves, or furnaces. CO poisoning occurs when CO accumulates in the bloodstream and can result in severe tissue damage or even death. Many types of CO sensors have been reported, including electrochemical, semiconductor metal-oxide, catalytic combustion, thermal conductivity, and infrared absorption-type for the detection of CO. However, despite their excellent selectivity and sensitivity, issues such as complexity, power consumption, and calibration limit their applications. In this study, a fabricbased colorimetric CO sensor is proposed to address these issues. Potassium disulfitopalladate (II) (K2Pd(SO3)2) is dyed on a polyester fabric as a sensing material for selective CO detection. The sensing characteristics and performance are investigated using optical instruments such as RGB sensor and spectrometer. The sensor shows immediate color change when exposed to CO at a concentration that is even lower than 20 ppm before 2 min. The fast response time of the sensor is attributed to its high porosity to react with CO. This easy-to-fabricate and cost-effective sensor can detect and prevent the leakage of CO simultaneously with high sensitivity and selectivity toward CO.

Blood amyloid β oligomerization as a biomarker of Alzheimer’s disease: a blinded validation study

2020 ◽  
Author(s):  
Young Chul Youn ◽  
Byoung Sub Lee ◽  
Gwang Je Kim ◽  
Ji Sun Ryu ◽  
Kuntaek Lim ◽  
...  
Keyword(s):  
Clinical Diagnosis ◽  
Sensitivity And Specificity ◽  
Detection System ◽  
Amyloid Β ◽  
High Sensitivity ◽  
Community Based ◽  
Clinical Sensitivity ◽  
Aβ Oligomerization ◽  
Normal Cognition

Abstract INTRODUCTION: Oligomeric amyloid ß (Aß) is one of the major contributors to the pathomechanism of AD; Aß oligomerization in plasma can be measured using a Multimer Detection System-Oligomeric Aß (MDS-OAß) after incubation with spiked synthetic Aß. METHODS: We evaluated the clinical sensitivity and specificity of the MDS-OAß values by inBlood TM OAß test using heparin-treated plasma samples from 52 AD patients in comparison with 52 community-based subjects with normal cognition (NC). The inclusion criterion was proposed by the NINCDS-ADRDA and additionally required for the least 6 months of follow-up from the initial clinical diagnosis in the course of AD. RESULTS: The MDS-OAβ values were 1.43 ± 0.30 ng/ml in AD and 0.45 ± 0.19 ( p <0.001) in NC, respectively. Using a cut-off value of 0.78 ng/ml, the results revealed that 100% sensitivity 92.31% specificity. DISCUSSION: MDS-OAß to measure plasma Aβ oligomerization is a valuable blood-based biomarker for clinical diagnosis of AD, with high sensitivity and specificity.

High sensitivity acetylene detection system based on cavity enhanced absorption technique

2012 ◽  
Vol 20 (1) ◽  
pp. 9-16
Author(s):  
陈霄 CHEN Xiao ◽  
隋青美 SUI Qing-mei ◽  
苗飞 MIAO Fei ◽  
贾磊 JIA Lei ◽  
曹玉强 CAO Yu-qiang
Keyword(s):  
Detection System ◽  
High Sensitivity ◽  
Enhanced Absorption ◽  
Absorption Technique
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