scholarly journals A Smart Colorimetric Platform for Detection of Methanol, Ethanol and Formic Acid

Sensors ◽  
2022 ◽  
Vol 22 (2) ◽  
pp. 618
Author(s):  
Mizaj Shabil Sha ◽  
Muni Raj Maurya ◽  
Mithra Geetha ◽  
Bijandra Kumar ◽  
Aboubakr M. Abdullah ◽  
...  
Keyword(s):  
Formic Acid ◽  
Limit Of Detection ◽  
Colorimetric Method ◽  
Cost Effective ◽  
Co2 Conversion ◽  
New Approach ◽  
Novel Approach ◽  
Carbon Dioxide Co2 ◽  
Optimized Conditions ◽  
Real Time Application

Carbon dioxide (CO2) is a greenhouse gas in the atmosphere and scientists are working on converting it to useful products, thereby reducing its quantity in the atmosphere. For converting CO2, different approaches are used, and among them, electrochemistry is found to be the most common and more efficient technique. Current methods for detecting the products of electrochemical CO2 conversion are time-consuming and complex. To combat this, a simple, cost-effective colorimetric method has been developed to detect methanol, ethanol, and formic acid, which are formed electrochemically from CO2. In the present work, the highly efficient sensitive dyes were successfully established to detect these three compounds under optimized conditions. These dyes demonstrated excellent selectivity and showed no cross-reaction with other products generated in the CO2 conversion system. In the analysis using these three compounds, this strategy shows good specificity and limit of detection (LOD, ~0.03–0.06 ppm). A cost-effective and sensitive Internet of Things (IoT) colorimetric sensor prototype was developed to implement these dyes systems for practical and real-time application. Employing the dyes as sensing elements, the prototype exhibits unique red, green, and blue (RGB) values upon exposure to test solutions with a short response time of 2 s. Detection of these compounds via this new approach has been proven effective by comparing them with nuclear magnetic resonance (NMR). This novel approach can replace heavy-duty instruments such as high-pressure liquid chromatography (HPLC), gas chromatography (G.C.), and NMR due to its extraordinary selectivity and rapidity.

Novel HILIC-ESI-MS method for urinary profiling of MSUD and methylmalonic aciduria biomarkers

2019 ◽  
Vol 57 (8) ◽  
pp. 715-723
Author(s):  
Elizabeth Mary Mathew ◽  
Leslie Lewis ◽  
Pragna Rao ◽  
K Nalini ◽  
Asha Kamath ◽  
...  
Keyword(s):  
Formic Acid ◽  
Malonic Acid ◽  
Limit Of Detection ◽  
Cost Effective ◽  
Methylmalonic Aciduria ◽  
Limit Of Quantification ◽  
Maple Syrup ◽  
Effective Manner ◽  
Branched Chain ◽  
Development And Validation

AbstractMethyl malonic acid and branched-chain keto acids are important biomarkers for the diagnosis of cobalamin deficiencies and maple syrup urine disease. We report the development and validation of a HILIC-ESI-MS2 method for the quantification of these organic acids from neonatal urine. The samples were 100 times diluted and analyzed on a ZIC-HILIC column with 25-mM formic acid in water: 25-mM formic acid in acetonitrile (45:55) at a flow rate of 0.8 mL/min with a runtime of only 6 minutes. The method demonstrated a lower limit of detection of 10 ng/mL, Limit of Quantification (LOQ) of 50 ng/mL, linearity of r2 ≥ 0.990 and recoveries of 87–105% for all analytes. The intraday and interday precision CV’s were <10% and 12%, respectively. Extensive stability studies demonstrated the analytes to be stable in stock and in matrix with a percent change within ±15%. The Bland–Altman analysis of the developed method with the gold standard GCMS method demonstrated a bias of 0.44, 0.11, 0.009 and –0.19 for methyl malonic acid, 3-methyl-2-oxovaleric acid, 2-hydroxy-3methylbutyric acid and 4-methyl-2-oxovaleric acid, respectively, proving the methods are comparable. The newly developed method involves no derivatization and has a simple sample preparation and a low runtime, enabling it to be easily automated with a high sample throughput in a cost-effective manner.

Colorimetric Sensing of Methyl Parathion Using Nanozymatic Activity of Gold Nanoparticles

2020 ◽  
Vol 12 (2) ◽  
pp. 232-241
Author(s):  
Anjana Pandey ◽  
Saumya Srivastava ◽  
Gayatri ◽  
Priya Rai ◽  
Ashutosh Pandey
Keyword(s):  
Gold Nanoparticles ◽  
Methyl Parathion ◽  
Limit Of Detection ◽  
Colorimetric Assay ◽  
Cost Effective ◽  
Colorimetric Sensing ◽  
Electron Transfer Mechanism ◽  
Au Nps ◽  
New Approach ◽  
Cost Effective Technique

In this study, we have used new approach for detection of the methyl parathion residues i.e., by inhibiting half of the peroxidase-like activity of gold nanoparticles. We have investigated the peroxidase like activity of gold nanoparticles by colorimetric assay and optimized the pH, temperature, incubation time and different concentrations of H2O2 by using TMB as substrate as well as organophosphates effect on their enzyme mimetic activity. Kinetic study of gold nanoparticles has shown better catalytic activity than horseradish peroxidase at pH 3.5. The peroxidase substrate TMB (3,3,5,5-tetramethylbenzidine) can be oxidized by H2O2 by the enzymatic action of the gold nanoparticles resulting in a blue-coloured product, oxidized TMB. The principle involved behind the inhibition of enzymatic activity of nanozyme is due to hindrance of electron transfer mechanism TMB-H2O2-Au NPs system by the methyl parathion. The peroxidase activity is selectively reduced with increasing methyl parathion concentration. This sensing method has lowest limit of detection of 78.95 nM. This study can be used for development of sensitive and cost effective technique for sensing of harmful pesticides.

Supercritical Fluid Extraction of Bioactive Compounds from Plant Materials

2017 ◽  
Vol 100 (6) ◽  
pp. 1624-1635 ◽  
Author(s):  
Olga Wrona ◽  
Katarzyna Rafińska ◽  
Cezary Możeński ◽  
Bogusław Buszewski
Keyword(s):  
Supercritical Fluid Extraction ◽  
Supercritical Fluid ◽  
Cost Effective ◽  
Fluid Extraction ◽  
Plant Materials ◽  
New Approach ◽  
Effective Manner ◽  
Carbon Dioxide Co2 ◽  
Selection Of ◽  
Material Extraction

Abstract There has been growing interest in the application of supercritical solvents over the last several years, many of the applications industrial in nature. The purpose of plant material extraction is to obtain large amounts of extract rich in the desired active compounds in a time-sensitive and cost-effective manner. The productivity and profitability of a supercritical fluid extraction (SFE) process largely depends on the selection of process parameters, which are elaborated upon in this paper. Carbon dioxide (CO2) is the most desirable solvent for the supercritical extraction of natural products. Its near-ambient critical temperature makes it suitable for the extraction of thermolabile components without degradation. A new approach has been adopted for SFE in which the solubility of nonpolar supercritical CO2 can be enhanced by the addition of small amounts of cosolvent.

scholarly journals Estimation of Catechin in Ayurvedic Oil Formulations Containing Acacia catechu

2009 ◽  
Vol 92 (4) ◽  
pp. 1021-1026 ◽  
Author(s):  
Nidhi Dubey ◽  
Nitin Dubey ◽  
Rajendra Mehta ◽  
Ajay Saluja
Keyword(s):  
Formic Acid ◽  
Limit Of Detection ◽  
Linear Regression Analysis ◽  
Cost Effective ◽  
Analysis Data ◽  
Calibration Plot ◽  
Tlc Plates ◽  
Acacia Catechu ◽  
Hptlc Method

Abstract A sensitive, simple, rapid, and efficient HPTLC method was developed and validated for the analysis of catechin in marketed Ayurvedic oil formulations containing Acacia catechu. Chromatography of methanolic0.1 formic acid (7:3, v/v) extracts of these formulations was performed on silica gel 60 F254 aluminum-backed TLC plates of 0.2 mm layer thickness. The plate was developed up to 85 mm with the ternarymobile phase chloroformacetone0.1 formic acid (7.7 + 1.5 + 0.8, v/v/v) at 22 2C with 20 min of chamber saturation. The system produced compact spots of catechin at an Rf value of 0.36. The marker, catechin, was quantified at its maximum absorbance of 296 nm. The limit of detection and quantitation values were 6 and 20 ng/spot, respectively. The linear regression analysis data for the calibration plot showed a good linear relationship with a correlation coefficient of 0.9993 in the concentration range of 2001200 ng/spot for catechin with respect to peak area. Repeatability of the method was 0.88 RSD. Recovery values from 97 to 102 indicate excellent accuracy of the method. The developed HPTLC method is accurate, precise, and cost-effective, and it can be successfully applied for the determination of catechin in marketed Ayurvedic oil formulations containing Acacia catechu.

scholarly journals Carbon-Doping as Efficient Strategy for Improving Photocatalytic Activity of Polysilicon Supported Pd in Hydrogen Evolution from Formic Acid

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3919
Author(s):  
Amal Al-Azmi ◽  
Sajjad Keshipour
Keyword(s):  
Photocatalytic Activity ◽  
Citric Acid ◽  
Formic Acid ◽  
Cost Effective ◽  
Pd Nanoparticles ◽  
Carbon Doping ◽  
Turnover Frequency ◽  
New Approach ◽  
Carbon Doped ◽  
Supported Pd

Interest in cost-effective materials pushes researchers to the inexpensive and abundant semiconductors to use photons’ energy for generating electrons and holes required for photocatalytic transformations. At the same time, polysilicon is one of the economic semiconductors with a disadvantage of high bandgap which could be solved by carbon-doping. We employed this strategy to the synthesis of carbon-doped polysilicon by a new approach starting from citric acid and methyltrimethoxysilane. The nanocomposite obtained was utterly characterized, and compared with bare polysilicon; increased UV–Vis absorbance and shift to higher wavelengths were the most notable characteristics of the synthesized catalyst. The carbon-doped polysilicon was modified with Pd nanoparticles to obtain a new heterogeneous photocatalyst for the formic acid degradation. The decomposition of formic acid was photocatalyzed by the obtained nanocomposite with a hydrogen production turnover frequency of up to 690 h−1. Moreover, it was demonstrated that the catalyst is stable and recyclable.

scholarly journals AS1411-Templated Fluorescent Cu Nanomaterial’s Synthesis and Its Application to Detecting Melamine

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Lu Ga ◽  
Jun Ai ◽  
Yong Wang
Keyword(s):  
Ascorbic Acid ◽  
Linear Relationship ◽  
Correlation Coefficient ◽  
Fluorescence Intensity ◽  
Room Temperature ◽  
Cost Effective ◽  
Good Linear ◽  
Milk Samples ◽  
Novel Approach ◽  
Optimized Conditions

Herein, we report a novel approach to AS1411-templated formation of fluorescent copper nanomaterials and their application to melamine detection. Fluorescent copper nanomaterials were formed at room temperature by using AS1411 as a template and ascorbic acid as reductant. However, the fluorescence intensity decreased obviously in the presence of melamine. Under the optimized conditions, the quenching fluorescence intensities of copper nanomaterials showed a good linear relationship with the concentration of melamine in the range of 50 μmol/L–120 μmol/L, and the correlation coefficient was 0.9823. In addition, the method was successfully applied in the detection of melamine in milk samples. This method was cost-effective and convenient without any labels or complicated operations. Thus, this work successfully develops the capping AS1411 scaffolds of copper nanomaterials detection of melamine.

scholarly journals A novel approach for assessing the interaction of masonry walls under vertical loads

2005 ◽  
Vol 32 (4) ◽  
pp. 601-614
Author(s):  
Márcio R.S Corrêa ◽  
Adrian W Page
Keyword(s):  
Load Transfer ◽  
Design Procedure ◽  
Cost Effective ◽  
Masonry Walls ◽  
Shear Stresses ◽  
New Approach ◽  
Load Bearing ◽  
Parabolic Distribution ◽  
Novel Approach ◽  
Full Scale Tests

This paper investigates the behaviour of masonry load-bearing walls subjected to differential vertical load. A new approach for evaluating the interaction of intersecting walls is used, focusing on the mechanism of load transfer and the resulting shear stresses. The study is carried out using finite element modelling. Previous full-scale tests are used to verify the features of the numerical model. Once confirmed, the model is then used to study the phenomenon, varying parameters such as the number of floors and the dimensions of the walls. It is shown that the distance down the wall at which homogenization of the applied loads occurs can be predicted by application of the Saint Venant's Principle. The distribution of shear stresses along the interface can be simulated by a simple parabolic distribution. A simple design procedure is proposed, allowing more realistic, cost-effective designs of load-bearing masonry structures.Key words: masonry, walls, vertical loads, finite elements, interaction of walls.

Janus – A New Approach to Air Combat Pilot Training

2019 ◽  
Vol 2019 (4) ◽  
pp. 7-22
Author(s):  
Georges Bridel ◽  
Zdobyslaw Goraj ◽  
Lukasz Kiszkowiak ◽  
Jean-Georges Brévot ◽  
Jean-Pierre Devaux ◽  
...  
Keyword(s):  
Low Cost ◽  
Cost Effective ◽  
High Energy ◽  
Training System ◽  
Embedded Sensors ◽  
Pilot Training ◽  
New Approach ◽  
Combat Aircraft ◽  
Air Combat ◽  
The Cost

Abstract Advanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training. Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.

Green Synthesis and Spectroscopic Studies of Ag-rGO Nanocomposites for Highly Selective Mercury (II) Sensing

2018 ◽  
Vol 9 (1) ◽  
pp. 101-108 ◽  
Author(s):  
Shubhangi J. Mane-Gavade ◽  
Sandip R. Sabale ◽  
Xiao-Ying Yu ◽  
Gurunath H. Nikam ◽  
Bhaskar V. Tamhankar
Keyword(s):  
Green Synthesis ◽  
Color Change ◽  
Limit Of Detection ◽  
Aqueous Media ◽  
Suitable Condition ◽  
Cost Effective ◽  
Spectroscopic Studies ◽  
Calibration Plot ◽  
First Time

Introduction: Herein we report the green synthesis and characterization of silverreduced graphene oxide nanocomposites (Ag-rGO) using Acacia nilotica gum for the first time. Experimental: We demonstrate the Hg2+ ions sensing ability of the Ag-rGO nanocomposites form aqueous medium. The developed colorimetric sensor method is simple, fast and selective for the detection of Hg2+ ions in aqueous media in presence of other associated ions. A significant color change was noticed with naked eye upon Hg2+ addition. The color change was not observed for cations including Sr2+, Ni2+, Cd2+, Pb2+, Mg2+, Ca2+, Fe2+, Ba2+ and Mn2+indicating that only Hg2+ shows a strong interaction with Ag-rGO nanocomposites. Under the most suitable condition, the calibration plot (A0-A) against concentration of Hg2+ was linear in the range of 0.1-1.0 ppm with a correlation coefficient (R2) value 0.9998. Results & Conclusion The concentration of Hg2+ was quantitatively determined with the Limit of Detection (LOD) of 0.85 ppm. Also, this method shows excellent selectivity towards Hg2+ over nine other cations tested. Moreover, the method offers a new cost effective, rapid and simple approach for the detection of Hg2+ in water samples.

Sign in / Sign up

Export Citation Format

Share Document