Read by QxMD icon Read

ACS Sensors

Ji Yeon Hwang, Sang Tae Kim, Junyoung Kwon, Jaebeom Lee, Young-Ok Chun, Jin Soo Han, Ho-Seong Han
Circulating tumor cells (CTCs) have considerable clinical significance in cancer progression and prognosis. In this context, CTC-derived microRNAs (miRs) in blood and tissues have been proposed as the novel non-invasive biomarkers for monitoring tumor progression, especially, at the early stages. To monitor circulating miRs, a tool should have high sensitivity, be a simple procedure, and allow detection in very small volumes. Thus, we designed a sensing tool for sensitive monitoring of blood or tissue miRs using a fluorophore-quencher probe-based molecular beacon (MB)...
November 14, 2018: ACS Sensors
Ketki Chawla, Mario M Modena, Paolo S Ravaynia, Flavio C Lombardo, Martin Leonhardt, Gordana Panic, Sebastian C Bürgel, Jennifer Keiser, Andreas Hierlemann
Schistosomiasis is a neglected tropical disease, caused by parasitic worms, which affects almost 200 millions people worldwide. For over 40 years, chemotherapeutic treatment has relied on the administration of praziquantel, an efficacious drug against schistosomiasis. However, concerns about developing drug resistance require the discovery of novel drug compounds. Currently, the drug-screening process is mostly based on the visual evaluation of drug effects on worm larvae in vitro by a trained operator. This manual process is extremely labor-intensive, has limited throughput and may be affected by subjectivity of the operator evaluation...
November 14, 2018: ACS Sensors
Xiaojun Liu, Conghui Huang, Chenghua Zong, Aiye Liang, Zhangjian Wu, Yusu Zhang, Qingquan Zhang, Wenfeng Zhao, Hongwei Gai
We developed a single-molecule homogeneous immunoassay by counting spatially "overlapping" two-color quantum dots (QD) under a wide-field fluorescence microscope. QD 655 with red fluorescence and QD 565 with green fluorescence were modified with capture and detection antibodies, respectively. A capture antibody-modified QD 655 and a detection antibody-modified QD 565 were conjugated by a corresponding antigen molecule to form a "sandwich" immunocomplex. The conjugated QD 655 could not be distinguished from the conjugated QD 565 by fluorescent microscopy because the distance between them was smaller than the resolution of an optical microscope (approximately 200 nm)...
November 14, 2018: ACS Sensors
Makusu Tsutsui, Kazumichi Yokota, Tomoko Nakada, Akihide Arima, Wataru Tonomura, Masateru Taniguchi, Takashi Washio, Tomoji Kawai
Utilization of multiple-channel structure is a promising way of accomplishing high-throughput detections of analytes in solid-state pore sensors. Here we report on systematic investigation of particle capture efficiency in Si3 N4 multipore systems of various array configurations. We demonstrated enhanced detection throughput with increasing numbers of pore channels in a membrane. Meanwhile, we also observed significant contributions of the interchannel crosstalk in closely integrated multipores that tended to deteriorate throughput performance by causing shrinkage of the absorption zone via the interference-derived weakening of the electric field around the pore orifice...
November 13, 2018: ACS Sensors
Stephanie Hui Kit Yap, Yi-Hsin Chien, Rex Tan, Abdul Rahman Bin Shaik Alauddin, Wen Bin Ji, Swee Chuan Tjin, Ken-Tye Yong
This study demonstrated a L-glutathione-modified non-adiabatic microfiber sensor to detect trace level of heavy metal ion in aqueous solution. The sensor showed an exclusively selective response to Pb2+ among other metal ions and a measured detection limit of 5g/L, lower than the maximum allowable limit of Pb2+ in drinking water by WHO. Moreover, a novel compact all-fiber-based interrogation scheme was proposed to promote the development of a portable handheld system for on-site measurement. The presented scheme does not require costly and bulky laboratory equipment but operates based on the reflected optical power of two fiber Bragg gratings (FBG), measured using photodetectors independently...
November 13, 2018: ACS Sensors
Sirsendu Bhowmick, Jun Wang
Multiplex measurement of protein expression with the single-cell resolution has been challenging. Although a few conventional approaches including flow cytometry and immunofluorescence-based methods have been developed to detect proteins in individual cells, they are either dependent on bulky instrument or not multiplexed and high-throughput enough. Here we present a portable single-cell analysis system that is operable in a resource-limited environment. A stand-sit microchip housed in a clamp enables simple and instrument-free operation of all necessary steps, and the detection based on immunogold enhancement exonerates the reliance on fluorescence optics and electronics...
November 13, 2018: ACS Sensors
Qian Han, Jianping Liu, Qingtao Meng, Yong-Lei Wang, Huan Feng, Zhiqiang Zhang, Zhi Ping Xu, Run Zhang
An effective bioanalytical method for rapid, sensitive, specific, and in situ sensing of nitric oxide (NO) is the key for further unveiling the biological functions of this gasotransmitter molecule in vitro and in vivo. In this contribution, a new fluorescence probe for sensing and imaging of NO in live systems was developed. The probe, FP-NO, was designed by exploring a novel sensing mechanism, i.e., the rotation of the N-N single bond of a coumarin derivative. FP-NO was prepared by incorporating a recognition unit, thiosemicarbazide moiety into a coumarin fluorophore...
November 13, 2018: ACS Sensors
Suphasinee Sateanchok, Nadezda Pankratova, Maria Cuartero, Thomas Cherubini, Kate Grudpan, Eric Bakker
There is an urgent need for reliable seawater phosphate measuring tools to better assess eutrophication. Today, most accepted sensing approaches are based on the established colorimetric molybdenum blue assay. It requires one to modify the sample to strongly acidic conditions and to add various reagents, principally molybdate and reducing agent (e.g., ascorbic acid), to form a blue colored phosphate complex that is subsequently detected spectrophotometrically. The associated need for large sample and mobile phase reservoirs and mixing coils are, unfortunately, not ideally adapted for the development of operationally simple in situ sensing instruments...
November 12, 2018: ACS Sensors
Cui Lai, Shiyu Liu, Chen Zhang, Guangming Zeng, Danlian Huang, Lei Qin, Xigui Liu, Huan Yi, Rongzhong Wang, Fanglong Huang, Bisheng Li, Tianyu Hu
A renewable electrochemical aptasensor was proposed for super sensitive determination of Hg2+. The novel aptasensor, based on sulfur-nitrogen co-doped ordered mesoporous carbon (SN-OMC) and thymine-Hg2+-thymine (T-Hg2+-T) mismatch structure, used ferrocene as signal molecules to achieve the conversion of current signals. In the absence of Hg2+, the thiol modified T-rich probe 1 spontaneously formed a hairpin structure by base pairing. After hybridizing with the ferrocene-labeled probe 2 in the presence of Hg2+, the hairpin structure of probe 1 was opened due to the preferentially formation of T-Hg2+-T mismatch structure and the ferrocene signal molecules approached the modified electrode surface...
November 9, 2018: ACS Sensors
Nesmine Maptue, Weina Jiang, Crystal Harrison, Alexander M Funk, Gaurav Sharma, Craig R Malloy, Dean Sherry, Chalermchai Khemtong
13 C Magnetic resonance imaging of hyperpolarized (HP) 13 C-enriched bicarbonate (H13 CO3 - ) and carbon dioxide (13 CO2 ) is a novel and sensitive technique for tissue pH mapping in vivo. Administration of the HP physiological buffer pair is attractive, but poor polarization and the short T1 of 13 C-enriched inorganic bicarbonate salts are major drawbacks for this approach. Here, we report a new class of mixed anhydrides for esterase-catalyzed production of highly polarized 13 CO2 and H13 CO3 - in tissue. A series of precursors with different alkoxy and acyl groups were synthesized and tested for chemical stability and T1 ...
November 9, 2018: ACS Sensors
Beichen Lin, Jin Xu, Kunning Lin, Mingpo Li, Miao Lu
This study proposed a low-cost sensor for in-situ automatic monitoring of phosphate and nitrite in agricultural water environments, involving a series of "Fish-Bite" reservoirs, multiple reagent capsules, and a colorimetric sensor. The "Fish-Bite" reservoir is an alternative to the pumps, valves and filters that are widely used for water sample collection, and also offers a closed cell for chromogenic reactions afterwards. Up to two capsules can be embedded in each reservoir to support chromogenic reactions that use two different reagents in sequence...
November 8, 2018: ACS Sensors
Tesfalem Geremariam Welearegay, Mohamed Fethi Diouani, Lars Österlund, Florina Ionescu, Kamel Belgacem, Hanen Smadhi, Samira Khaled, Abdelhamid Kidar, Umut Cindemir, Dhafer Laouini, Radu Ionescu
Human cutaneous leishmaniasis, although designated as one of the most neglected tropical diseases, remains underestimated due to its misdiagnosis. The diagnosis is mainly based on the microscopic detection of amastigote forms, isolation of the parasite, or the detection of Leishmania DNA, in addition to its differential clinical characterization; these tools are not always available in routine daily practice, and they are expensive and time consuming. Here we present a simple-to-use, non-invasive approach for human cutaneous leishmaniasis diagnosis, which is based on the analysis of volatile organic compounds in exhaled breath with an array of specifically-designed chemical gas sensors...
November 7, 2018: ACS Sensors
Mengmeng Song, Lantu Dang, Juan Long, Chengguo Hu
We report here a simple filtration method for the scalable fabrication of user-designed and carbon nanomaterial-based electrode arrays using laser-cut polyvinyl chloride (PVC) tape templates. This method can produce electrode arrays with high uniformity and low resistance from the dilute dispersions of single-walled carbon nanotubes (SWNTs) and graphene nanoplatelets (GNPs). For these two carbon arrays, the SWNTs array is demonstrated to possess several interesting properties, e.g., good mechanical property, excellent flexibility and favorable electrochemical behaviors...
November 7, 2018: ACS Sensors
Maral P S Mousavi, Mohamed K Abd El-Rahman, Amr M Mahmoud, Rania M Abdelsalam, Philippe Buhlmann
The neurotransmitter acetylcholine (ACh) plays a key role in the pathophysiology of brain disorders such as Alzheimer's disease. Understanding the dynamics of ACh concentration changes and kinetics of ACh degradation in the living brain is crucial to unravel the pathophysiology of such diseases and the rational design of therapeutics. In this work, an electrochemical sensor capable of dynamic, label-free, selective, and in-situ detection of ACh in a range of 1 nM to 1 mM (with temporal resolution of less than one second) was developed...
November 6, 2018: ACS Sensors
Jai Kyoung Sim, Bongyoung Ahn, Il Doh
This study proposes a skin analysis device using a truncate hollow cone (THC) probe for measuring both transepidermal water loss (TEWL) and skin hardness. Because skin health is closely related to the epidermal barrier function and skin mechanical property, it is important to measure their biophysical indicators at the same time, to understand skin conditions and diagnose skin disorders such as atopic dermatitis and systemic sclerosis. Previous skin analyzers, however, required different probes with different protocols for each biophysical indicators, which makes the measurement inconvenient and increases the measurement uncertainty...
November 6, 2018: ACS Sensors
Jennifer H Granger, Marc D Porter
This paper describes preliminary results on the surprising impact of human serum as a sample matrix on the detectability of protective antigen (PA) and lethal factor (LF), two antigenic protein markers of Bacillus anthracis, in a heterogeneous immunometric assay. Two sample matrices were examined: human serum and physiological buffer. Human serum is used as a specimen in the diagnostic testing of potentially infected individuals. Physiological buffers are often applied to the recovery of biomarkers dispersed in suspicious white powders and other suspect specimens and as a serum diluent to combat contributions to the measured test response from nonspecific adsorption...
November 6, 2018: ACS Sensors
Wei-Lun Hsu, Junho Hwang, Hirofumi Daiguji
In this work, we study transport-induced-charge electroosmosis toward alternating current resistive pulse sensing for the next generation of biomedical applications. Transport-induced-charge electroosmosis, being a new class of electrokinetic phenomenon, occurs as a salt concentration gradient works in synergy with an electric field in ultrathin nanopores. Apart from the conventional electric double layer-governed electroosmotic flow in which the flow behavior is subject to the surface charge, it is found that the transport-induced-charge electroosmotic flow behaves independently of surface charge magnitude but can be linearly regulated by the bulk salt concentration bias...
November 5, 2018: ACS Sensors
Ellairaja Sundaram, Venkatesan Subramanian, Kumaravel Velayutham, Rohini Gomathinayagam, Vairathevar Sivasamy Vasantha
A very simple chemodosimeter has been developed for creatinine biomolecules based on Michael addition reaction by using ( E)-3-(Pyren-2-yl)-1-(3,4,5-trimethoxyphenyl)prop-2- en-1-one Chalcone. The photophysical properties of the chalcone were thoroughly analyzed using UV-vis and emission techniques. The chalcone has exhibited two absorption maxima at 297 and 407 nm which are due n-π* and π-π* transactions, respectively. This property was further confirmed by repeating UV-vis absorbance studies of the chalcones in different solvents having different polarity...
November 5, 2018: ACS Sensors
Gaser N Abdelrasoul, Scott MacKay, Saad Y Salim, Kathleen P Ismond, Marcus Tamura, Charfeddine Khalifa, Emma Mannan, Donghai Lin, Tanushree Mandal, Ruth R Montgomery, David S Wishart, Jie Chen, Rachel G Khadaroo
Inadequate blood supply to the intestine can lead to acute mesenteric ischemia (AMI), with a mortality rate ranging from 60% to 90%. This high mortality rate is partially due to late detection and the lack of efficient early diagnostic tests. There is an urgent need for a point-of-care tool for immediate bedside diagnosis. Here we present for the first time a rapid and non-invasive electrochemical biosensor device based on non-faradic impedance spectroscopy to detect intestinal fatty-acid binding protein (I-FABP) as an indication of AMI...
November 5, 2018: ACS Sensors
Xinyuan Zhou, Anqi Wang, Ying Wang, Luozhen Bian, Zai-Xing Yang, Yuzhi Bian, Yan Gong, Xiaofeng Wu, Ning Han, Yunfa Chen
Though the chemical origin of a metal oxide gas sensor is widely accepted to be the surface reaction of detectants with ionsorbed oxygen, how the sensing material transduces the chemical reaction into electrical signal (i.e. resistance change) is still not well recognized. Herein, the single ZnO NW is used as a model to investigate the relationship between the microstructure and sensing performance. It is found that the acetone responses arrive at the maximum at the NW diameter (D) of ~110 nm at the D range of 80 nm to 400 nm, which is even the temperature independent at the temperature region of 200 ℃-375 ℃...
November 2, 2018: ACS Sensors
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"