scholarly journals A Novel Quinoxaline-Rhodamine Conjugate for a Simple and Efficient Detection of Hydrogen Sulphate Ion

Compounds ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 29-40
Author(s):  
Sutapa Sahu ◽  
Yeasin Sikdar ◽  
Riya Bag ◽  
Dilip K. Maiti ◽  
José P. Cerón-Carrasco ◽  
...  
Keyword(s):  
Solid Phase ◽  
Detection Limits ◽  
Hydrogen Sulfate ◽  
Absorption And Emission ◽  
Conjugate System ◽  
Colorimetric Chemosensor ◽  
Simple Strategy ◽  
Efficient Detection ◽  
Hydrogen Sulphate

This work presents the development of a quinoxaline and rhodamine conjugate system that acts as a colorimetric chemosensor for hydrogen sulfate (HSO4−) ions in methanol media. This sensor has been characterized both theoretically and experimentally. The detection limits for HSO4− are small as 0.71 µM and 3.8 µM for the absorption and emission experiments, respectively. The effectiveness of the probe in recognizing HSO4− both in gel and solid phase is evaluated as well. Thus, this works presents a simple strategy to detect the environmental HSO4− pollutant event at tiny concentrations.

A Decade of Development in Immunoassay Methodology

1990 ◽  
Vol 36 (8) ◽  
pp. 1408-1427 ◽  
Author(s):  
James P Gosling
Keyword(s):  
Monoclonal Antibodies ◽  
Liquid Phase ◽  
Analytical Methods ◽  
Clinical Laboratory ◽  
Solid Phase ◽  
Detection Limits ◽  
Assay System ◽  
Future Trends ◽  
Homogeneous Systems ◽  
Major Trend

Abstract Immunoassays are now very widely used in the clinical laboratory, either because no other type of assay system is feasible or because they are often the most effective and suitable of the possible analytical methods. The last decade has seen the development and refinement of many new immunoassay reagents and systems. The major trend has been away from liquid-phase assays involving radioisotopic labels, towards fast homogeneous or solid-phase assays capable of operation anywhere; and towards precise and reliable nonisotopic, automated or semi-automated laboratory assays, often with detection limits measured in pico- or attomoles. The use of monoclonal antibodies is now widespread, and the methodologies of labels and of solid-phase components are much more sophisticated. New assay formulations, novel homogeneous systems, immunosensors, free-analyte assays, the importance of thorough validation and of interfering substances, and future trends are discussed.

scholarly journals Determination of Citrinin in Barley by Indirect and Direct Enzyme Immunoassay

1996 ◽  
Vol 79 (6) ◽  
pp. 1325-1329 ◽  
Author(s):  
David Abramson ◽  
Ewald Usleber ◽  
Erwin Martlbauer
Keyword(s):  
Enzyme Immunoassay ◽  
Solid Phase ◽  
Polyclonal Antibodies ◽  
Detection Limits ◽  
Keyhole Limpet Hemocyanin ◽  
Buffer Solutions ◽  
Microtiter Plates ◽  
Coefficients Of Variation ◽  
Optimum Extraction

Abstract Polyclonal antibodies against the mycotoxin citrinin were raised in rabbits after immunization with citrinin conjugated to keyhole limpet hemocyanin. The antibodies were used in a competitive indirect enzyme immunoassay (EIA) with citrinin coupled to glucose oxidase as the solid-phase antigen for coating microtiter plates. Detection limits of this indirect EIA for citrinin ranged from 0.4 to 0.8 ng/mL for buffer solutions. Recoveries of citrinin added to ground barley at 100–2000 ng/g ranged from 105 to 112%, with coefficients of variation between 4.5 and 12%. A direct competitive EIA also was established, with citrinin coupled to horseradish peroxidase as the labeled antigen. Detection limits of this direct EIA for citrinin ranged from 2 to 4 ng/mL for buffer solutions. Recoveries of citrinin added to ground barley at 500–2000 ng/g ranged from 108 to 111%, with coefficients of variation between 8.4 and 26.9%. In naturally contaminated barley samples assayed with the indirect EIA, optimum extraction of citrinin was obtained in 30 min, and only one extraction was necessary to recover 72–76% of the analyte.

scholarly journals Determination of Some Aldehydes by Using Solid-Phase Microextraction and High-Performance Liquid Chromatography with UV Detection

2007 ◽  
Vol 90 (6) ◽  
pp. 1689-1694 ◽  
Author(s):  
Ashwini Kumar ◽  
Baldev Singh ◽  
Ashok Kumar Malik ◽  
Dhananjay K Tiwary
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Solid Phase Microextraction ◽  
High Performance ◽  
Solid Phase ◽  
Detection Limits ◽  
Uv Detection ◽  
New Approach ◽  
Better Than

Abstract A new approach has been developed for the extraction and determination of aldehydes such as veratraldehyde, m-nitrobenzaldehyde, cinnamaldehyde, benzaldehyde, and p-chlorobenzaldehyde by using solid-phase microextraction (SPME) and high-performance liquid chromatography with UV detection (HPLC/UV). The method involves adsorption of the aldehydes on polydimethylsiloxane/divinylbenzenecoated fiber, followed by desorption in the desorption chamber of the SPME-HPLC interface, using acetonitrilewater (70 + 30) as the mobile phase; UV detection was at 254 nm. A good separation of 5 aldehydes was obtained on a C18 column. The detection limits of veratraldehyde, m-nitrobenzaldehyde, cinnamaldehyde, benzaldehyde, and p-chlorobenzaldehyde are 25, 41, 13, 12, and 11 pg/mL, respectively, which are about 100 times better than the detection limits for other SPME methods using gas chromatography. The proposed method was validated by determining benzaldehyde in bitter almonds and cinnamaldehyde in cinnamon bark. The recoveries of the 5 analytes were determined by analysis of spiked drinking water.

Solid-Phase Extraction of Carbofuran, Atrazine, Simazine, Alachlor, and Cyanazine from Shallow Well Water

1990 ◽  
Vol 73 (3) ◽  
pp. 438-442 ◽  
Author(s):  
Ralph G Nash
Keyword(s):  
Solid Phase Extraction ◽  
Solid Phase ◽  
Detection Limits ◽  
Geological Survey ◽  
Well Water ◽  
Phase Extraction

Abstract Extraction of several nitrogen-containing pesticides from water on solid-phase C18 cartridges was rapid and accurate. One analyst can extract >48 samples/day. Recovery efficiencies were 77, 95, 92, 90, and 99% with detection limits of 0.20, 0.05, 0.05, 0.20, and 0.10 /μg/L for carbofuran, atrazine, simazine, alachlor, and, cyanazine, respectively. Extraction of the atrazine and simazine dealkylation products (deethylatrazlne and deethylsimazine) was less efficient, e.g., 26 and 9%, respectively. Comparisons with 10 U.S. Geological Survey samples gave similar results

scholarly journals A Novel Fluorescence and SPE Adsorption Nanomaterials of Molecularly Imprinted Polymers Based on Quantum Dot-Grafted Covalent Organic Frameworks for the High Selectivity and Sensitivity Detection of Ferulic Acid

Nanomaterials ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 305 ◽  
Author(s):  
Yu Wang ◽  
Yuzhen Wang ◽  
Huilin Liu
Keyword(s):  
Quantum Dot ◽  
Ferulic Acid ◽  
Molecularly Imprinted Polymers ◽  
Solid Phase ◽  
Synthesis Method ◽  
Hydroxyl Groups ◽  
Covalent Organic Frameworks ◽  
Molecularly Imprinted ◽  
Imprinted Polymers ◽  
Efficient Detection

A fluorescence and solid phase extraction (SPE) adsorption nanomaterials of molecularly imprinted polymers (MIPs) based on quantum dot-grafted covalent organic frameworks (QD-grafted COFs) was prepared by one-pot surface-imprinting synthesis method. Amino groups of silane reagent were at the surface of QDs to coordinate COFs efficiently by Schiff-base reactions, providing thermal and chemical stability to MIPs. It also reacted with the phenolic hydroxyl groups of ferulic acid (FA) through non-covalent interactions. The nanomaterials were used as fluorescence sensing and SPE adsorption toward determination of ferulic acid. The MIPs based on QD-grafted COFs had good fluorescence response ability, and quenching linearly at concentrations of ferulic acid from 0.03 to 60 mg kg−1, with a detection limit of 5 µg kg−1. At the same time, it exhibited a good SPE adsorption ability, and the FA extraction was from 1.63 to 3.11 mg kg−1 in grain by-products by SPE coupled with high performance liquid chromatography/mass spectrometry (HPLC/MS). The fluorescence and SPE-HPLC/MS were used for the efficient detection of ferulic acid in real samples with recovery values of 88–114% and 90–97%, respectively. Furthermore, the nanomaterials of MIPs based on QD-grafted COFs were used for FA detection with high sensitivity and selectivity, and it also increased the recycling of waste resources.

Determination of Nonylphenol and Octylphenol in Seawater Samples Using Solid-Phase Microextraction Procedures Coupled to Gas Chromatography–Mass Spectrometry

2012 ◽  
Vol 518-523 ◽  
pp. 1496-1500 ◽  
Author(s):  
Xian Yin Ping ◽  
Hui Sheng Zhuang
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Detection Limits ◽  
Operating Conditions ◽  
Gas Chromatography Mass Spectrometry ◽  
Chromatography Mass Spectrometry ◽  
Seawater Samples

The solid-phase microextraction (SPME) technique with on-fiber derivatization coupled to gas chromatography–mass spectrometry was evaluated for the analysis of technical nonylphenol (NP) and octylphenol (OP). The optimization of operating conditions influencing the performances of SPME and derivatization were studied in detail. The optimised method was linear over the range studied and showed good level of precision, with a RSD lower than 10% and detection limits at and 0.003 μgL−1for OP and 0.032μgL−1for NP, respectively. The results obtained from different seawater samples revealed the presence of the target compounds, at levels ranging between 0.034 and 0.186 μgL−1.

Introduction of O-sulfonated poly(vinylpyrrolidonium) hydrogen sulfate as an efficient, and reusable solid acid catalyst for some solvent-free multicomponent reactions

RSC Advances ◽  
2016 ◽  
Vol 6 (50) ◽  
pp. 44794-44806 ◽  
Author(s):  
Omid Goli-Jolodar ◽  
Farhad Shirini ◽  
Mohadeseh Seddighi
Keyword(s):  
Multicomponent Reactions ◽  
Solid Acid ◽  
Solid Acid Catalyst ◽  
Acid Catalyst ◽  
Acidity Function ◽  
Hydrogen Sulfate ◽  
Hammett Acidity Function ◽  
Ft Ir ◽  
Hydrogen Sulphate ◽  
Sulfonated Poly

In this work, O-sulfonated poly(vinylpyrrolidonium) hydrogen sulphate has been prepared as a powerful recyclable solid acid catalyst and characterized using a variety of techniques including elemental analysis, FT-IR, TGA, SEM, XRD, pH analysis and Hammett acidity function.

Synthesis of 1,4-Dihydropyridine as a Fluorescent and Colorimetric Chemosensor for Detection of Fe3+ Ion

2019 ◽  
Vol 17 (10) ◽  
pp. 747-754
Author(s):  
Zohreh Kheil Kordi ◽  
Ghodsi Mohammadi Ziarani ◽  
Alireza Badiei ◽  
Negar Lashgari
Keyword(s):  
Ammonium Acetate ◽  
Detection Limits ◽  
Colorimetric Sensor ◽  
Colorimetric Chemosensor ◽  
Vis Spectroscopy

A new fluorescent and colorimetric sensor for Fe3+ ion were synthesized via four-component reaction of acetophenone, dimedone, benzaldehyde and ammonium acetate in the presence of SrFe12O19. The chemosensor shows excellent sensitivity toward Fe3+ ion. The sensing ability of the chemosensor was studied by fluorescent and UV-Vis spectroscopy. The detection limits for Fe3+ were calculated respectively about 8.3 × 10–6 M and 2.3 × 10–6 M for fluorescence and UV-Vis techniques.

Kinetics of H+/Na+ solid-phase ion exchange on iron(III) hydrogen sulfate

2008 ◽  
Vol 53 (4) ◽  
pp. 520-523
Author(s):  
Yu. A. Karavanova ◽  
I. A. Stenina ◽  
A. B. Yaroslavtsev
Keyword(s):  
Ion Exchange ◽  
Solid Phase ◽  
Hydrogen Sulfate ◽  
Kinetics Of
Sign in / Sign up

Export Citation Format

Share Document