journal
MENU ▼
Read by QxMD icon Read
search

Sensors and Actuators. B, Chemical

journal
https://www.readbyqxmd.com/read/29255341/miniaturized-planar-room-temperature-ionic-liquid-electrochemical-gas-sensor-for-rapid-multiple-gas-pollutants-monitoring
#1
Hao Wan, Heyu Yin, Lu Lin, Xiangqun Zeng, Andrew J Mason
The growing impact of airborne pollutants and explosive gases on human health and occupational safety has escalated the demand of sensors to monitor hazardous gases. This paper presents a new miniaturized planar electrochemical gas sensor for rapid measurement of multiple gaseous hazards. The gas sensor features a porous polytetrafluoroethylene substrate that enables fast gas diffusion and room temperature ionic liquid as the electrolyte. Metal sputtering was utilized for platinum electrodes fabrication to enhance adhesion between the electrodes and the substrate...
February 2018: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/29180835/laminated-and-infused-parafilm%C3%A2-paper-for-paper-based-analytical-devices
#2
Yong Shin Kim, Yuanyuan Yang, Charles S Henry
Numerous fabrication methods have been reported for microfluidic paper-based analytical devices (μPADs) using barrier materials ranging from photoresist to wax. While these methods have been used with wide success, consistently producing small, high-resolution features using materials and methods that are compatible with solvents and surfactants remains a challenge. Two new methods are presented here for generating μPADs with well-defined, high-resolution structures compatible with solvents and surfactant-containing solutions by partially or fully fusing paper with Parafilm® followed by cutting with a CO2 laser cutter...
February 2018: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/29225421/flow-through-microfluidic-immunosensors-with-refractive-index-matched-silica-monoliths-as-volumetric-optical-detection-elements
#3
M S Wiederoder, E L Kendall, J-H Han, R G Ulrich, D L DeVoe
A sensitive and rapid absorbance based immunosensor that utilizes ex situ functionalized porous silica monoliths as volumetric optical detection elements is demonstrated in this study. The porous monolith structure facilitates high capture probe density and short diffusion length scales, enabling sensitive and rapid assays. Silica monoliths, synthesized and functionalized with immunocapture probes off-chip before integration into a sealed thermoplastic microfluidic device, serve to capture target antigens during perfusion through the porous structure...
January 2018: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/29200660/measuring-ultra-low-levels-of-nucleotide-biomarkers-using-quartz-crystal-microbalance-and-spr-microarray-imaging-methods-a-comparative-analysis
#4
Gayan Premaratne, Zainab H Al Mubarak, Lakmini Senavirathna, Lin Liu, Sadagopan Krishnan
Circulating serum nucleotide biomarkers are useful indicators for early diagnosis of cancer, respiratory illnesses, and other deadly diseases. In this work, we compared detection performances of a quartz crystal microbalance (QCM), which is a mass sensor, with that of a surface plasmon resonance (SPR) microarray for an oligonucleotide mimic of a microRNA-21 biomarker. A surface immobilized capture oligonucleotide probe was used to hybridize with the target oligonucleotide (i.e., the microRNA-21 mimic) to facilitate selective detection...
December 2017: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/29200659/electrochemical-detection-of-urinary-micrornas-via-sulfonamide-bound-antisense-hybridisation
#5
Daniel A Smith, Lucy J Newbury, Guido Drago, Timothy Bowen, James E Redman
Altered serum and plasma microRNA (miRNA) expression profiles have been observed in numerous human diseases, with a number of studies describing circulating miRNA biomarkers for cancer diagnosis, prognosis and response to treatment, and recruitment to clinical trials for miRNA-based drug therapy already underway. Electrochemical detection of biomarkers in urine has several significant advantages over circulating biomarker analysis including safety, cost, speed and ease of conversion to the point of care environment...
December 2017: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/29033497/investigation-into-the-ring-substituted-polyanilines-and-their-application-for-the-detection-and-adsorption-of-sulfur-dioxide
#6
Yuhong Tian, Ke Qu, Xiangqun Zeng
It has been demonstrated in this study that the substituents on the monomer aniline benzene ring are able to introduce the significant differences to the resulting polyaniline's collective properties. We systematically evaluated the structural perturbation effects of two substituents (methyl and methoxy) of aniline monomer through the electrochemical method. Our results showed that the methoxy group induces the less structural perturbation than the methyl counterpart, because of its partial double bond restriction...
October 2017: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/28970651/a-flexible-ag-agcl-micro-reference-electrode-based-on-a-parylene-tube-structure
#7
Zhiguo Zhao, Hongen Tu, Eric Gr Kim, Bonnie F Sloane, Yong Xu
In the effort of developing micro-electrochemical sensors, the miniaturization of reference electrodes has been a challenging task. In this paper, a flexible micro reference electrode with an internal electrolyte reservoir is reported. This new device is based on a unique microfabricated parylene tube structure, which is filled with Cl(-) rich electrolyte, into which a 50 μm diameter silver (Ag) wire covered with a 7.4 μm thick silver chloride (AgCl) layer is inserted. The distal end of the tube is filled with potassium chloride (KCl) saturated agarose gel...
August 2017: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/28966475/centrifugal-microfluidics-for-sorting-immune-cells-from-whole-blood
#8
Zeta Tak For Yu, Jophin George Joseph, Shirley Xiaosu Liu, Mei Ki Cheung, Parker James Haffey, Katsuo Kurabayashi, Jianping Fu
Sorting and enumeration of immune cells from blood are critical operations involved in many clinical applications. Conventional methods for sorting and counting immune cells from blood, such as flow cytometry and hemocytometers, are tedious, inaccurate, and difficult for implementation for point-of-care (POC) testing. Herein we developed a microscale centrifugal technology termed Centrifugal Microfluidic Chip (CMC) capable of sorting immune cells from blood and in situ cellular analysis in a laboratory setting...
June 2017: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/28579695/self-powered-autonomous-biological-oxygen-demand-biosensor-for-online-water-quality-monitoring
#9
Grzegorz Pasternak, John Greenman, Ioannis Ieropoulos
Standard Biological Oxygen Demand (BOD) analysis requires 5 days to complete. To date, microbial fuel cell biosensors used as an alternative method for BOD assessment requires external apparatus, which limits their use for on-line monitoring in remote, off-grid locations. In this study, a self-powered, floating biosensor was developed for online water quality monitoring. This approach eliminated the need for external apparatus and maintenance that would otherwise be required by other techniques. The biosensor was able to detect urine in freshwater and turn ON a visual and sound cues (85 dB)...
June 2017: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/28529409/an-experimental-check-of-backscattering-interferometry
#10
Michael M Baksh, M G Finn
Backscattering interferometry (BSI) was used to determine the association constants for four well-known biomolecular interactions: protein A + IgG, trypsin + antitrypsin, trypsin + p-aminobenzamidine, and antithrombin + heparin. Each gave well-defined binding curves and Kd values in close agreement with published findings obtained using other techniques. These results stand in direct contrast to the claims in a 2015 publication in this journal (Discussion of "Back Scattering Interferometry revisited-a theoretical and experimental investigation" Jørgensen, T...
May 2017: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/28603384/rapid-measurement-of-room-temperature-ionic-liquid-electrochemical-gas-sensor-using-transient-double-potential-amperometry
#11
Hao Wan, Heyu Yin, Andrew J Mason
Intense study on gas sensors has been conducted to implement fast gas sensing with high sensitivity, reliability and long lifetime. This paper presents a rapid amperometric method for gas sensing based on a room temperature ionic liquid electrochemical gas sensor. To implement a miniaturized sensor with a fast response time, a three electrode system with gold interdigitated electrodes was fabricated by photolithography on a porous polytetrafluoroethylene substrate that greatly enhances gas diffusion. Furthermore, based on the reversible reaction of oxygen, a new transient double potential amperometry (DPA) was explored for electrochemical analysis to decrease the measurement time and reverse reaction by-products that could cause current drift...
April 2017: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/28533632/local-ph-monitoring-of-small-cluster-of-cells-using-a-fiber-optic-dual-core-micro-probe
#12
Sisi Chen, Qingbo Yang, Hai Xiao, Honglan Shi, Yinfa Ma
Biological studies of tissues and cells have enabled numerous discoveries, but these studies still bear potential risks of invalidation because of cell heterogeneity. Through high-accuracy techniques, recent studies have demonstrated that discrepancies do exist between the results from low-number-cell studies and cell-population-based results. Thus the urgent need to re-evaluate key principles on limited number of cells has been provoked. In this study, a novel designed dual-core fiber-optic pH micro-probe was fabricated and demonstrated for niche environment pH sensing with high spatial resolution...
March 31, 2017: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/28090149/multiplexed-and-fully-automated-detection-of-metabolic-biomarkers-using-microdialysis-probe
#13
Champak Das, Guochun Wang, Qian Sun, Bradley Ledden
We report here, the design and development of an automated near real-time continuous detection system for lactate, glutamate, pyruvate and glucose using microdialysis probe. The system developed can automatically push perfusate through microdialysis probe (20, 100 and 1000 kDa MWCO cutoff probe) at low to medium flow rate of 0.5-2 μL/min with almost 100% fluid recovery. The microdialysate collected from the probe is analyzed automatically for these four metabolite biomarkers. It operates in a continuous mode with measurements of all four biomarkers once every 20 min...
January 2017: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/27721570/a-hydrogel-based-glucose-affinity-microsensor
#14
Junyi Shang, Jing Yan, Zhixing Zhang, Xian Huang, Panita Maturavongsadit, Bing Song, Yuan Jia, Tieying Ma, Dachao Li, Kexin Xu, Qian Wang, Qiao Lin
We present a hydrogel-based affinity microsensor for continuous glucose measurements. The microsensor is based on microelectromechanical systems (MEMS) technology, and incorporates a synthetic hydrogel that is attached to the device surface via in situ polymerization. Glucose molecules that diffuses into and out of the device binds reversibly with boronic acid groups in the hydrogel via affinity binding, and causes changes in the dielectric properties of the hydrogel, which can be measured using a MEMS capacitive transducer to determine the glucose concentration...
December 2016: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/28713203/solvatochromic-fluorescent-probes-for-recognition-of-human-serum-albumin-in-aqueous-solution-insights-into-structure-property-relationship
#15
Bin Liu, Xiaoman Bi, Lucas McDonald, Yi Pang, Danqing Liu, Chengjun Pan, Lei Wang
Human serum albumin (HSA) as the most abundant protein in human blood plasma, serves many physiological functions. The dysregulation of HSA in serum or in urine is associated with various diseases, such as cirrhosis of liver, multiple myeloma, and cardiovascular disease. Therefore, to quantify HSA in body fluids with high selectivity and sensitivity is of great significance for disease diagnosis and preventive medicine. We herein developed a series of amide-functionalized flavonoids probes, 1-3, for recognition of human serum albumin...
November 29, 2016: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/27812240/investigation-of-the-h2s-poisoning-process-for-sensing-composite-material-based-on-carbon-nanotubes-and-metal-oxides
#16
Yichen Duan, Laurent Pirolli, Andrew V Teplyakov
The poisoning of H2S sensing material based on the mixture of acid-treated carbon nanotubes, CuO and SnO2 was investigated by exposing the material to high doses of H2S (1% in volume) and following the changes spectroscopically. The presence of metal sulfides (CuS and SnS2), sulfates and thiols was confirmed on the surface of this material as the result of H2S poisoning. Further study revealed that leaving this material in air for extended period of time led to reoxidation of metal sulfides back to metal oxides...
November 1, 2016: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/27773967/ultrasonic-transducer-guided-electrochemical-impedance-spectroscopy-to-assess-lipid-laden-plaques
#17
Jianguo Ma, Yuan Luo, René R Sevag Packard, Teng Ma, Yichen Ding, Parinaz Abiri, Yu-Chong Tai, Qifa Zhou, Kirk K Shung, Rongsong Li, Tzung Hsiai
Plaque rupture causes acute coronary syndromes and stroke. Intraplaque oxidized low density lipoprotein (oxLDL) is metabolically unstable and prone to induce rupture. We designed an intravascular ultrasound (IVUS)-guided electrochemical impedance spectroscopy (EIS) sensor to enhance the detection reproducibility of oxLDL-laden plaques. The flexible 2-point micro-electrode array for EIS was affixed to an inflatable balloon anchored onto a co-axial double layer catheter (outer diameter = 2 mm). The mechanically scanning-driven IVUS transducer (45 MHz) was deployed through the inner catheter (diameter = 1...
November 1, 2016: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/27725788/an-efficient-power-harvesting-mobile-phone-based-electrochemical-biosensor-for-point-of-care-health-monitoring
#18
Alexander C Sun, Chengyang Yao, A G Venkatesh, Drew A Hall
Cellular phone penetration has grown continually over the past two decades with the number of connected devices rapidly approaching the total world population. Leveraging the worldwide ubiquity and connectivity of these devices, we developed a mobile phone-based electrochemical biosensor platform for point-of-care (POC) diagnostics and wellness tracking. The platform consists of an inexpensive electronic module (< $20) containing a low-power potentiostat that interfaces with and efficiently harvests power from a wide variety of phones through the audio jack...
November 1, 2016: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/27721569/impedimetric-immunosensing-in-a-porous-volumetric-microfluidic-detector
#19
Michael S Wiederoder, Isaac Misri, Don L DeVoe
A sensitive and rapid impedemetric immunosensor is demonstrated utilizing porous volumetric microfluidic detection elements and silver enhanced gold nanoparticle probes. The porous detection elements significantly increase capture probe density and decrease diffusion length scales compared to conventional planar sensors to improve target capture efficiency and enhance impedance signal. In this work, a packed bed of silica beads functionalized with antibody probes serves as a porous sensor element within a thermoplastic microchannel, with an interdigitated gold electrode microarray used to measure impedance changes caused by the concentration dependent formation of silver aggregates...
October 29, 2016: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/27932855/the-i-o-transform-of-a-chemical-sensor
#20
Nalin Katta, Douglas C Meier, Kurt D Benkstein, Steve Semancik, Baranidharan Raman
A number of sensing technologies, using a variety of transduction principles, have been proposed for non-invasive chemical sensing. A fundamental problem common to all these sensing technologies is determining what features of the transducer's signal constitute a chemical fingerprint that allows for precise analyte recognition. Of particular importance is the need to extract features that are robust with respect to the sensor's age or stimulus intensity. Here, using pulsed stimulus delivery, we show that a sensor's operation can be modeled as a linear input-output (I/O) transform...
September 2016: Sensors and Actuators. B, Chemical
journal
journal
40224
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"