A rapid magnetic bead-based immunoassay for sensitive determination of diclofenac

Abstract Increasing contamination of environmental waters with pharmaceuticals represents an emerging threat for the drinking water quality and safety. In this regard, fast and reliable analytical methods are required to allow quick countermeasures in case of contamination. Here, we report the development of a magnetic bead-based immunoassay (MBBA) for the fast and cost-effective determination of the analgesic diclofenac (DCF) in water samples, based on diclofenac-coupled magnetic beads and a robust monoclonal anti-DCF antibody. A novel synthetic strategy for preparation of the beads resulted in an assay that enabled for the determination of diclofenac with a significantly lower limit of detection (400 ng/L) than the respective enzyme-linked immunosorbent assay (ELISA). With shorter incubation times and only one manual washing step required, the assay demands for remarkably shorter time to result (< 45 min) and less equipment than ELISA. Evaluation of assay precision and accuracy with a series of spiked water samples yielded results with low to moderate intra- and inter-assay variations and in good agreement with LC–MS/MS reference analysis. The assay principle can be transferred to other, e.g., microfluidic, formats, as well as applied to other analytes and may replace ELISA as the standard immunochemical method. Graphical abstract

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Pitfalls in the Immunochemical Determination of β‑Lactam Antibiotics in Water

Antibiotics ◽

10.3390/antibiotics10030298 ◽

2021 ◽

Vol 10 (3) ◽

pp. 298

Author(s):

Alexander Ecke ◽

Rudolf J. Schneider

Keyword(s):

Limit Of Detection ◽

Cost Effective ◽

Enzyme Linked Immunosorbent Assay ◽

Degree Of Hydrolysis ◽

Site Analysis ◽

Antibody Recognition ◽

Immunochemical Determination ◽

Key Factor ◽

Lactam Ring

Contamination of waters with pharmaceuticals is an alarming problem as it may support the evolution of antimicrobial resistance. Therefore, fast and cost-effective analytical methods for potential on-site analysis are desired in order to control the water quality and assure the safety of its use as a source of drinking water. Antibody-based methods, such as the enzyme-linked immunosorbent assay (ELISA), can be helpful in this regard but can also have certain pitfalls in store, depending on the analyte. As shown here for the class of β-lactam antibiotics, hydrolysis of the β‑lactam ring is a key factor in the immunochemical analysis as it influences antibody recognition. With the antibody used in this study, the limit of detection (LOD) in the immunoassay could be significantly reduced by hydrolysis for the five tested penicillins, with the lowest LOD for carbenicillin (0.2 nmol/L) and the greatest impact on penicillins G and V (reduction by 85%). In addition to enhanced quantification, our strategy also provides access to information about the degree of hydrolysis in water samples as shown for the most abundant penicillin amoxicillin.

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Detection of bisphenol A in water samples using ELISA determination method

Water Science & Technology Water Supply ◽

10.2166/ws.2011.008 ◽

2011 ◽

Vol 11 (1) ◽

pp. 55-60 ◽

Cited By ~ 4

Author(s):

J. Zheng ◽

S. Q. Zhao ◽

X. T. Xu ◽

K. Zhang

Keyword(s):

Drinking Water ◽

Bisphenol A ◽

Water Samples ◽

Limit Of Detection ◽

Industrial Effluent ◽

Cross Reactivity ◽

Enzyme Linked Immunosorbent Assay ◽

Uv Spectrophotometry ◽

Inhibition Concentration

In order to study whether bisphenol A (BPA) can pass into drinking water from polycarbonate barrel and exist in the river and industrial effluent the indirect competitive enzyme-linked immunosorbent assay (ELISA) for the determination of BPA was established. The results presented an inhibition concentration at 50% absorbance (IC50) of 0.123 mg L−1, and the limit of detection (LOD) is 9.934 μg L−1. The specificity of antiserum was proved well because the cross-reactivity with benzene, tert-butylbenzene, hydroquinone and o-hydroxybenzoic acid were found lower than 0.01%, except phenol was 0.26%. The method was found to be reliable and repeatable. It was used for monitoring the concentration of BPA in the barreled drinking water. The results confirmed BPA can pass into barreled drinking water from the polycarbonate barrel and concentration increased as days went on. A certain content of BPA was found in industrial effluent. The results of ELISA were consistent with the results of UV spectrophotometry. BPA could not be found in the water samples obtained from Zhujiang River. The established method shows specific recognition of BPA and could be applied in detection of environmental BPA.

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Immobilization-Free Electrochemical Sensor Coupled with a Graphene-Oxide-Based Aptasensor for Glycated Albumin Detection

Biosensors ◽

10.3390/bios11030085 ◽

2021 ◽

Vol 11 (3) ◽

pp. 85

Author(s):

Wassa Waiwinya ◽

Thitirat Putnin ◽

Dechnarong Pimalai ◽

Wireeya Chawjiraphan ◽

Nuankanya Sathirapongsasuti ◽

...

Keyword(s):

Graphene Oxide ◽

Electrochemical Sensor ◽

Detection Method ◽

Limit Of Detection ◽

Glycated Albumin ◽

Cost Effective ◽

Logarithmic Scale ◽

Electrochemical Aptasensor ◽

Alternative Approach

An immobilization-free electrochemical sensor coupled with a graphene oxide (GO)-based aptasensor was developed for glycated human serum albumin (GHSA) detection. The concentration of GHSA was monitored by measuring the electrochemical response of free GO and aptamer-bound GO in the presence of glycated albumin; their currents served as the analytical signals. The electrochemical aptasensor exhibited good performance with a base-10 logarithmic scale. The calibration curve was achieved in the range of 0.01–50 µg/mL. The limit of detection (LOD) was 8.70 ng/mL. The developed method was considered a one-drop measurement process because a fabrication step and the probe-immobilization process were not required. This simple sensor offers a cost-effective, rapid, and sensitive detection method, and could be an alternative approach for determination of GHSA levels.

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Determination of cobalt in water samples by atomic absorption spectrometry after pre-concentration with a simple ionic liquid-based dispersive liquid-liquid micro-extraction methodology

Open Chemistry ◽

10.2478/s11532-010-0030-2 ◽

2010 ◽

Vol 8 (3) ◽

pp. 617-625 ◽

Cited By ~ 18

Author(s):

Hossein Abdolmohammad-Zadeh ◽

Elnaz Ebrahimzadeh

Keyword(s):

Ionic Liquid ◽

Atomic Absorption Spectrometry ◽

Atomic Absorption ◽

Water Samples ◽

Limit Of Detection ◽

Absorption Spectrometry ◽

Experimental Conditions ◽

Flame Atomic Absorption ◽

Relative Standard

AbstractA rapid dispersive liquid-liquid micro-extraction (DLLME) methodology based on the application of 1-hexylpyridinium hexafluorophosphate [C6py][PF6] ionic liquid (IL) as an extractant solvent was applied for the pre-concentration of trace levels of cobalt prior to determination by flame atomic absorption spectrometry (FAAS). 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was employed as a chelator forming a Co-PMBP complex to extract cobalt ions from aqueous solution into the fine droplets of [C6py][PF6]. Some effective factors that influence the micro-extraction efficiency include the pH, the PMBP concentration, the amount of ionic liquid, the ionic strength, the temperature and the centrifugation time which were investigated and optimized. In the optimum experimental conditions, the limit of detection (3s) and the enrichment factor were 0.70 µg L−1 and 60, respectively. The relative standard deviation (RSD) for six replicate determinations of 50 µg L−1 Co was 2.36%. The calibration graph using the pre-concentration system was linear at levels 2–166 µg L−1 with a correlation coefficient of 0.9982. The applicability of the proposed method was evaluated by the determination of trace amounts of cobalt in several water samples.

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Characterization and validation of fragment antigen-binding (Fab) antibody-based immunoassay for deoxymiroestrol, a potent phytoestrogen from Pueraria candollei

10.22541/au.161270515.50311593/v1 ◽

2021 ◽

Author(s):

Worapol Sae-foo ◽

Supaluk Krittanai ◽

Wipawee Juengsanguanpornsuk ◽

Gorawit Yusakul ◽

Tharita Kitisripanya ◽

...

Keyword(s):

Quantitative Method ◽

Estrogenic Activity ◽

Limit Of Detection ◽

Hormone Replacement ◽

Enzyme Linked Immunosorbent Assay ◽

Antigen Binding ◽

Pueraria Candollei ◽

Specific Determination ◽

Fragment Antigen Binding

Deoxymiroestrol is the most potent phytoestrogen in chromenes group that has been found in Pueraria candollei, Thai name known as Kwao Krua Khao. Several studies reported estrogenic activity of P. candollei in order to using as hormone replacement therapy for postmenopausal women. Previously, specific determination of deoxymiroestrol content by enzyme-linked immunosorbent assay (ELISA) using polyclonal antibody (pAb) have been reported. However, production of pAb has limitation and variability from different batches. Therefore, in this study, we established quantitative method for determination of deoxymiroestrol using fragment antigen-binding (Fab) antibody-based immunoassay. The developed immunoassay has specificity to deoxymiroestrol with a calibration range of 15.6-1000 ng mL-1. Precision including intra-assay and inter-assay are 1.48-7.11 and 0.58-9.31%, respectively. Accuracy of the assay showed in recovery between 99.77-101.61% when spike deoxymiroestrol standard into the samples. The limit of detection (LOD) is 30.80 ng mL-1. Comparation antibody-based immunoassay for determination of deoxymiroestrol using Fab with pAb was represented consistency (R2 = 0.9807) when analysis roots bark of Pueraria candollei from difference areas. Therefore, this development assay can apply to determine deoxymiroestrol content in the plant samples.

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Proposal of De Novo Antigen Test for COVID-19: Ultrasensitive Detection of Spike Proteins of SARS-CoV-2

Diagnostics ◽

10.3390/diagnostics10080594 ◽

2020 ◽

Vol 10 (8) ◽

pp. 594 ◽

Cited By ~ 8

Author(s):

Yuta Kyosei ◽

Mayuri Namba ◽

Sou Yamura ◽

Rikiya Takeuchi ◽

Noriko Aoki ◽

...

Keyword(s):

De Novo ◽

Limit Of Detection ◽

False Negative ◽

Cost Effective ◽

Detection Sensitivity ◽

Enzyme Linked Immunosorbent Assay ◽

Antigen Test ◽

Virus Rna ◽

Antigen Tests ◽

Spike Proteins

Polymerase chain reaction (PCR)-based antigen tests are technically difficult, time-consuming, and expensive, and may produce false negative results requiring follow-up confirmation with computed tomography. The global coronavirus disease 2019 (COVID-19) pandemic has increased the demand for accurate, easy-to-use, rapid, and cost-effective antigen tests for clinical application. We propose a de novo antigen test for diagnosing COVID-19 using the combination of sandwich enzyme-linked immunosorbent assay and thio-nicotinamide adenine dinucleotide (thio-NAD) cycling. Our test takes advantage of the spike proteins specific to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. The limit of detection of our test was 2.3 × 10−18 moles/assay. If the virus has ~25 spike proteins on its surface, our method should detect on the order of 10−20 moles of virus/assay, corresponding to ~104 copies of the virus RNA/assay. The detection sensitivity approaches that of PCR-based assays because the average virus RNA load used for PCR-based assays is ~105 copies per oro- or naso-pharyngeal swab specimen. To our knowledge, this is the first ultrasensitive antigen test for SARS-CoV-2 spike proteins that can be performed with an easy-to-use microplate reader. Sufficient sensitivity can be achieved within 10 min of thio-NAD cycling. Our antigen test allows for rapid, cost-effective, specific, ultrasensitive, and simultaneous multiple measurements of SARS-CoV-2, and has broad application for the diagnosis for COVID-19.

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Rapid detection of Clostridium difficile via magnetic bead aggregation in cost-effective polyester microdevices with cell phone image analysis

The Analyst ◽

10.1039/c6an00674d ◽

2016 ◽

Vol 141 (19) ◽

pp. 5637-5645 ◽

Cited By ~ 14

Author(s):

Jacquelyn A. DuVall ◽

Scott T. Cabaniss ◽

Morgan L. Angotti ◽

John H. Moore ◽

Mayuresh Abhyankar ◽

...

Keyword(s):

Image Analysis ◽

Clostridium Difficile ◽

Rapid Detection ◽

Cell Phone ◽

Magnetic Beads ◽

Cost Effective ◽

Magnetic Bead ◽

Isothermal Amplification ◽

Specific Detection

A centrifugally-driven polyester microdevice for sequence-specific detection ofClostridium difficileusing magnetic beads, isothermal amplification, and cell phone image analysis.

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Determination of carcinogenic herbicides in milk samples using green non-ionic silicone surfactant of cloud point extraction and spectrophotometry

Royal Society Open Science ◽

10.1098/rsos.171500 ◽

2018 ◽

Vol 5 (4) ◽

pp. 171500 ◽

Cited By ~ 1

Author(s):

N. I. Mohd ◽

N. N. M. Zain ◽

M. Raoov ◽

S. Mohamad

Keyword(s):

Cloud Point ◽

Cloud Point Extraction ◽

Limit Of Detection ◽

Cost Effective ◽

Silicone Surfactant ◽

Extraction Solvent ◽

Milk Samples ◽

Relative Standard ◽

Limit Of Quantitation

A new cloud point methodology was successfully used for the extraction of carcinogenic pesticides in milk samples as a prior step to their determination by spectrophotometry. In this work, non-ionic silicone surfactant, also known as 3-(3-hydroxypropyl-heptatrimethylxyloxane), was chosen as a green extraction solvent because of its structure and properties. The effect of different parameters, such as the type of surfactant, concentration and volume of surfactant, pH, salt, temperature, incubation time and water content on the cloud point extraction of carcinogenic pesticides such as atrazine and propazine, was studied in detail and a set of optimum conditions was established. A good correlation coefficient ( R 2 ) in the range of 0.991–0.997 for all calibration curves was obtained. The limit of detection was 1.06 µg l −1 (atrazine) and 1.22 µg l −1 (propazine), and the limit of quantitation was 3.54 µg l −1 (atrazine) and 4.07 µg l −1 (propazine). Satisfactory recoveries in the range of 81–108% were determined in milk samples at 5 and 1000 µg l −1 , respectively, with low relative standard deviation, n = 3 of 0.301–7.45% in milk matrices. The proposed method is very convenient, rapid, cost-effective and environmentally friendly for food analysis.

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An Automated and High-Throughput Immunoaffinity Magnetic Bead-Based Sample Clean-Up Platform for the Determination of Aflatoxins in Grains and Oils Using UPLC-FLD

Toxins ◽

10.3390/toxins11100583 ◽

2019 ◽

Vol 11 (10) ◽

pp. 583 ◽

Cited By ~ 3

Author(s):

Zhihong Xuan ◽

Jin Ye ◽

Bing Zhang ◽

Li Li ◽

Yu Wu ◽

...

Keyword(s):

High Throughput ◽

High Performance ◽

Cost Effective ◽

Magnetic Bead ◽

The Novel ◽

Analysis Method ◽

Automated Method ◽

Accuracy And Precision ◽

Optimized Conditions

Sample clean-up remains the most time-consuming and error-prone step in the whole analytical procedure for aflatoxins (AFTs) analysis. Herein, an automated and high-throughput sample clean-up platform was developed with a disposable, cost-effective immunoaffinity magnetic bead-based kit. Under optimized conditions, the automated method takes less than 30 min to simultaneously purify 20 samples without requiring any centrifugation or filtering steps. When coupled to ultra-high performance liquid chromatography with fluorescence detection, this new analysis method displays excellent accuracy and precision as well as outstanding efficiency. Furthermore, an interlaboratory study was performed in six laboratories to validate the novel protocol. Mean recovery, repeatability, reproducibility, and Horwitz ratio values were within 91.9%–107.4%, 2.5%–7.4%, 2.7%–10.6%, and 0.26%–0.90, respectively. Results demonstrate that the developed sample clean-up platform is a reliable alternative to most widely adopted clean-up procedures for AFTs in cereals and oils.

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A Monoclonal Antibody-Based Enzyme-Linked Immunosorbent Assay for Determination of Homoharringtonine

Planta Medica ◽

10.1055/a-0578-8689 ◽

2018 ◽

Vol 84 (14) ◽

pp. 1038-1044 ◽

Cited By ~ 3

Author(s):

Benyakan Pongkitwitoon ◽

Seiichi Sakamoto ◽

Rika Nagamitsu ◽

Waraporn Putalun ◽

Hiroyuki Tanaka ◽

...

Keyword(s):

Monoclonal Antibody ◽

Immunosorbent Assay ◽

Myeloid Leukemia ◽

High Performance ◽

Sodium Periodate ◽

Limit Of Detection ◽

Enzyme Linked Immunosorbent Assay ◽

Study Support ◽

Mediated Oxidation

AbstractHomoharringtonine (HHT), also known as omacetaxine, is a natural compound found in the genus Cephalotaxus and is a promising pharmaceutical drug used for the treatment of chronic or accelerated phase chronic myeloid leukemia. As a tool for the quantitative determination of HHT, a specific monoclonal antibody against HHT (MAb 6A1) was generated by conjugates prepared via sodium periodate-mediated oxidation. The developed indirect competitive enzyme-linked immunosorbent assay (icELISA) using MAb 6A1 was found to be highly specific and sensitive with a limit of detection for HHT of 48.8 ng/mL. Validation assays to evaluate precision and accuracy of the method were conducted by the use of intra- and inter-assay analysis, recovery test, and comparison analysis between the amounts of HHT determined by ELISA and high-performance liquid chromatography. These results revealed that the established icELISA using MAb 6A1 is specific, sensitive, and reliable enough to be applied to the qualitative analysis for HHT. Furthermore, the results of this study support the usefulness of sodium periodate as a reagent for the conjugation between Cephalotaxus alkaloids and proteins for producing specific antibodies.

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