scholarly journals A Multifunctional Molecular Probe for Detecting Hg2+ and Ag+ Based on Ion-Mediated Base Mismatch

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3280 ◽  
Author(s):  
Luhui Wang ◽  
Yingying Zhang ◽  
Yafei Dong
Keyword(s):  
Environmental Samples ◽  
Low Cost ◽  
Logic Gate ◽  
Fluorescent Labeling ◽  
Molecular Probe ◽  
Strand Displacement ◽  
Orthogonal Experiments ◽  
Base Mismatch ◽  
Optimized Conditions ◽  
Or Logic Gate

In this paper, a multifunctional biosensing platform for sensitively detecting Hg2+ and Ag+, based on ion-mediated base mismatch, fluorescent labeling, and strand displacement, is introduced. The sensor can also be used as an OR logic gate, the multifunctional design of sensors is realized. Firstly, orthogonal experiments with three factors and three levels were carried out on the designed sensor, and preliminary optimization of conditions was performed for subsequent experiments. Next, the designed sensor was tested the specificity and target selectivity under the optimized conditions, and the application to actual environmental samples further verified the feasibility. Generally, this is a convenient, fast, stable, and low-cost method that provides a variety of ideas and an experimental basis for subsequent research.

Preparation of Solar-Grade Polysilicon by Acid Leaching

2010 ◽  
Vol 160-162 ◽  
pp. 1297-1300
Author(s):  
Yu Chang ◽  
Hong Yu Chen ◽  
Qi Wen Luo ◽  
Qi Hui Ye
Keyword(s):  
Grain Size ◽  
Removal Efficiency ◽  
Low Cost ◽  
Acid Leaching ◽  
Operating Conditions ◽  
Process Conditions ◽  
Primary Process ◽  
Optimal Operating ◽  
Orthogonal Experiments ◽  
Optimized Conditions

A low-cost acid leaching process is studied in this paper to prepare solar-grade polysilicon. The effects of process conditions (grain size, acid species and concentration, leaching time and temperature) are discussed. The further optimized conditions by orthogonal experiments are given in this paper. Optimal operating conditions are suggested: 75μm of grain size, 80 min of leaching time, 0.28 mol/l of concentration of HF, 80 C of leaching temperature. The removal efficiency of impurity reaches 98.41%. Analysis by ICP-AES and SEM illustrates acid leaching appears to be a potential primary process for solar-grade Si purification. .

An optical DNA logic gate based on strand displacement and magnetic separation, with response to multiple microRNAs in cancer cell lysates

2017 ◽  
Vol 184 (8) ◽  
pp. 2505-2513 ◽  
Author(s):  
Xiaoting Ji ◽  
Haoyuan Lv ◽  
Minghui Ma ◽  
Binglin Lv ◽  
Caifeng Ding
Keyword(s):  
Magnetic Separation ◽  
Cancer Cell ◽  
Logic Gate ◽  
Strand Displacement ◽  
Cell Lysates

Low-cost BSA technique for threshold-logic gate based multiplier implementations

1997 ◽  
Vol 33 (12) ◽  
pp. 1028
Author(s):  
J.M. Quintana ◽  
M.J. Avedillo ◽  
A. Rueda
Keyword(s):  
Low Cost ◽  
Logic Gate ◽  
Threshold Logic

scholarly journals DETERMINATION OF BTEX IN ENVIRONMENTAL SAMPLES: DEVELOPMENT AND PROTECTION OF TECHNOLOGIES AND ANALYTICAL METHODS

2019 ◽  
Vol 16 (31) ◽  
pp. 431-439
Author(s):  
Helilma de Andréa PINHEIRO ◽  
Ana Paula Mota FERREIRA ◽  
Ismael Carlos Braga ALVES ◽  
Antônio Fernandes SANTOS JÚNIOR ◽  
Raquel Bezerra dos Santos SAWCZUK ◽  
...  
Keyword(s):  
Petroleum Hydrocarbons ◽  
Environmental Samples ◽  
Low Cost ◽  
The United States ◽  
Operational Control ◽  
Toxic Compounds ◽  
Chromatographic Techniques ◽  
Benzene Toluene ◽  
And Storage

The contamination of water and soil by petroleum hydrocarbons is reported quite frequently, mainly due to accidents involving transport and storage of fuels. Among the most toxic compounds the most volatile benzene, toluene, ethylbenzene and xylene (BTEX). Residues of these compounds can cause serious environmental and public health troubles. Thus, more sensitive, selective and low-cost techniques, focused on the analysis and monitoring of these contaminants are being developed in order to establish operational control and to comply with local laws, but the intellectual property of such technologies is still unknown. The present study shows the panorama about patents, thesis and dissertations which have been already published on this theme. Together, the United States and China hold the largest number of patents, and most of thesis/dissertations describe methodologies for BTEX detection in water, although numerous environmental problems caused by oils in the soil had been reported. Also, the methods based on chromatographic techniques stand out in relation to the other techniques. It was possible to verify important advances in the field of sensors, especially the electrochemical ones, in order to solve the analytical gaps.

Sensitive Electrochemical Detection of 2,4-Dichlorophenol Using Novel Carbon Fiber Microelectrode

2011 ◽  
Vol 391-392 ◽  
pp. 1387-1391
Author(s):  
Zhan Jun Yang ◽  
Xiao Chun Huang ◽  
Juan Li ◽  
Yan Yan Ren ◽  
Xiao Ya Hu
Keyword(s):  
Electron Microscopy ◽  
Cyclic Voltammetry ◽  
Detection Limit ◽  
Carbon Fiber ◽  
Low Cost ◽  
Promising Alternative ◽  
Carbon Fiber Microelectrode ◽  
Electrochemical Signal ◽  
Analytical System ◽  
Optimized Conditions

A novel electrochemical strategy was proposed for detection of 2,4-Dichlorophenol (2,4-DCP) at fabricated carbon fiber microelectrode (CFME). The resultant CFME was characterized using scan electron microscopy (SEM) and cyclic voltammetry (CV). Upon addition of surfactant TritonX-100 in analytical system, the electrochemical signal of 2,4-DCP was obviously increased. Under the optimized conditions, the resulted CFME showed wide linear range for 2,4-DCP from 3.0×10-8to 1.8×10-6M with the detection limit of 1.0×10-8M (S/N = 3). The proposed method is simple, low-cost and convenient and will be a promising alternative for CFME fabrication.

Genetic Evolution for the Development of Robust Artificial Neural Network Logic Gates

2009 ◽  
Author(s):  
Anthony M. Roy ◽  
Erik K. Antonsson ◽  
Andrew A. Shapiro
Keyword(s):  
Logic Gate ◽  
Logic Gates ◽  
Design Methods ◽  
Neural Net ◽  
C Programs ◽  
Artificial Neural Net ◽  
Classical Design ◽  
Artificial Neural ◽  
Exclusive Or ◽  
Or Logic Gate

Control tasks involving dramatic non-linearities, such as decision making, can be challenging for classical design methods. However, autonomous stochastic design methods have proved effective. In particular, Genetic Algorithms (GA) that create phenotypes by the application of genotypes comprising rules are robust and highly scalable. Such encodings are useful for complex applications such as artificial neural net design. This paper outlines an evolutionary algorithm that creates C++ programs which in turn create Artificial Neural Networks (ANNs) that can functionally perform as an exclusive-OR logic gate. Furthermore, the GAs are able to create scalable ANNs robust enough to feature redundancies that allow the network to function despite internal failures.

scholarly journals Engineering of Bifunctional Enzymes with Uricase and Peroxidase Activities for Simple and Rapid Quantification of Uric Acid in Biological Samples

Catalysts ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 428
Author(s):  
Thanawat Phuadraksa ◽  
Jurairat Chittrakanwong ◽  
Kittitouch Tullayaprayouch ◽  
Naruthai Onsirisakul ◽  
Sineewanlaya Wichit ◽  
...  
Keyword(s):  
Uric Acid ◽  
Low Cost ◽  
Colorimetric Detection ◽  
Amplex Red ◽  
Bifunctional Enzymes ◽  
Bifunctional Proteins ◽  
Frame Fusion ◽  
The Cost ◽  
Optimized Conditions ◽  
Catalyzed Oxidation

Serum uric acid (SUA) is an important biomarker for prognosis and management of gout and other diseases. The development of a low-cost, simple, rapid and reliable assay for SUA detection is of great importance. In the present study, to save the cost of enzyme production and to shorten the reaction time for uric acid quantification, bifunctional proteins with uricase and peroxidase activities were engineered. In-frame fusion of Candida utilis uricase (CUOX) and Vitreoscilla hemoglobin (VHb) resulted in two versions of the bifunctional protein, CUOX-VHb (CV) and VHb-CUOX (VC). To our knowledge, this is the first report to describe the production of proteins with uricase and peroxidase activities. Based on the measurement of the initial rates of the coupled reaction (between uricase and peroxidase), CV was proven to be the most efficient enzyme followed by VC and native enzymes (CUOX+VHb), respectively. CV was further applied for the development of an assay for colorimetric detection of SUA, which was based on VHb-catalyzed oxidation of Amplex Red in the presence of hydrogen peroxide (H2O2). Under the optimized conditions, the assay exhibited a linear relationship between the absorbance and UA concentration over the range of 2.5 to 50 μM, with a detection limit of 1 μM. In addition, the assay can be performed at a single pH (8.0) so adjustment of the pH for peroxidase activity was not required. This advantage helped to further reduce costs and time. The developed assay was also successfully applied to detect UA in pooled human serum with the recoveries over 94.8%. These results suggest that the proposed assay holds great potential for clinical application.

scholarly journals Brilliant Green and Acid Orange 74 Dyes Removal from Water by Pinus roxburghii Leaves in Naturally Benign Way: An Application of Green Chemistry

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Rabia Rehman ◽  
Sara Jan Muhammad ◽  
Muhammad Arshad
Keyword(s):  
Brilliant Green ◽  
Low Cost ◽  
Kinetic Studies ◽  
Agitation Speed ◽  
Pinus Roxburghii ◽  
Acid Orange ◽  
Pseudo Second Order ◽  
Optimized Conditions ◽  
Adsorbent Dose ◽  
Dyes Removal

The purpose of this study was to use low cost and easily accessible biosorbent for batch-scale elimination of brilliant green and acid orange 74 dyes from aqueous solution. Pinus roxburghii leaves were utilized to study their dye-eliminating capacities. The adsorbent was characterized by FTIR, TGA, DTA, and SEM. The optimized conditions for brilliant green and acid orange 74 dye elimination were adsorbent dose, 1.2 and 1.8 g; contact time, 30 and 45 min; pH, 2 and 1; temperature, 50°C and 60°C; and agitation speed, 125 rpm and 50 rpm for BG and AO-74, respectively. Adsorption records well fitted Langmuir isotherm. Possibility of the procedure was shown by negative values of the thermodynamic parameter ∆G° for both dyes. Kinetic studies showed that adsorption of BG and AO-74 dyes from watery solution by PR leaves followed pseudo-second-order kinetics.

scholarly journals Highly Selective, Aptamer-Based, Ultrasensitive Nanogold Colorimetric Smartphone Readout for Detection of Cd(II)

Molecules ◽  
2019 ◽  
Vol 24 (15) ◽  
pp. 2745 ◽  
Author(s):  
Lu Xu ◽  
Jun Liang ◽  
Yonghui Wang ◽  
Shuyue Ren ◽  
Jin Wu ◽  
...  
Keyword(s):  
Limit Of Detection ◽  
Low Cost ◽  
Quantitative Detection ◽  
Practical Application ◽  
Full Agreement ◽  
Experimental Conditions ◽  
Dose Time ◽  
Dimethyl Ammonium ◽  
Rice Samples ◽  
Optimized Conditions

A highly selective and sensitive method for Cd(II) detection was developed based on aptamer and gold nanoparticles (AuNPs) combined with a colorimetric smartphone readout. The experimental conditions such as reaction time of polydiene dimethyl ammonium chloride (PDDA) and AuNPs, PDDA dose, time of aptamer and PDDA incubation, and aptamer concentration were optimized. Under the optimized conditions, the color and red(R) value of the solution was concentration-dependent on Cd(II). The proposed method exhibited a linear range of 1–400 ng/mL (r2 = 0.9794) with a limit of detection (LOD) of 1 ng/mL. This method had been successfully applied to test and quantify Cd(II) in water and rice samples, and the results were in full agreement with those from the atomic absorption spectrometer. Therefore, low-cost colorimetry demonstrated its potential for practical application in visual or quantitative detection with a smartphone. This approach can be readily applied to other analytes.

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