Development of rapid and cost-effective top-loading device for the detection of anti-SARS-CoV-2 IgG/IgM antibodies

AbstractInfection with SARS-CoV-2, the Betacoronavirus, caused a pandemic that affected the globe negatively. The gold method, RT-PCR, can detect SARS-CoV-2 but it is time-consuming and needs sophisticated equipment and professional personnel. On the other hand, rapid tests offer fast results and can detect anti-SARS-CoV-2 antibodies (Abs). The aim of this study is to develop a new rapid and cost-effective method for the detection of anti-SARS-CoV-2 IgG/IgM Abs. A new top-loading detection device was developed and composed of a small piece of plastic (25 × 25 × 0.5 mm) with an opening in the center, a piece of nitrocellulose (NC) membrane enough to block the opening from one side and adhesive tape to affix the NC to the plastic piece. The NC is blotted with anti-human IgG/IgM and rabbit serum. The device was evaluated against a commercially available IgG/IgM ELISA detection kit using normal, Covid-19-positive, HCV, HBV, and Cytomegalovirus-positive sera. Outcomes demonstrated simplicity, reproducibility, and accuracy of the new device and results can be obtained in less than 5 min. We anticipate our developed assay method to be used widely in point of care before deciding on the use of expensive nucleic acid assays.

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Aptamer-Based Diagnostic Systems for the Rapid Screening of TB at the Point-of-Care

Diagnostics ◽

10.3390/diagnostics11081352 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1352

Author(s):

Darius Riziki Martin ◽

Nicole Remaliah Sibuyi ◽

Phumuzile Dube ◽

Adewale Oluwaseun Fadaka ◽

Ruben Cloete ◽

...

Keyword(s):

Low Income ◽

Point Of Care ◽

Health Care Systems ◽

Cost Effective ◽

Rapid Screening ◽

Low Income Countries ◽

Sputum Smear ◽

Diagnostic Systems ◽

Molecular Tests ◽

Rapid Tests

The transmission of Tuberculosis (TB) is very rapid and the burden it places on health care systems is felt globally. The effective management and prevention of this disease requires that it is detected early. Current TB diagnostic approaches, such as the culture, sputum smear, skin tuberculin, and molecular tests are time-consuming, and some are unaffordable for low-income countries. Rapid tests for disease biomarker detection are mostly based on immunological assays that use antibodies which are costly to produce, have low sensitivity and stability. Aptamers can replace antibodies in these diagnostic tests for the development of new rapid tests that are more cost effective; more stable at high temperatures and therefore have a better shelf life; do not have batch-to-batch variations, and thus more consistently bind to a specific target with similar or higher specificity and selectivity and are therefore more reliable. Advancements in TB research, in particular the application of proteomics to identify TB specific biomarkers, led to the identification of a number of biomarker proteins, that can be used to develop aptamer-based diagnostic assays able to screen individuals at the point-of-care (POC) more efficiently in resource-limited settings.

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Diagnostic optical sequencing

10.1101/685792 ◽

2019 ◽

Author(s):

Lee E. Korshoj ◽

Prashant Nagpal

Keyword(s):

Single Molecule ◽

Point Of Care ◽

Cost Effective ◽

Diagnostic Methods ◽

Sequencing Platform ◽

Molecular Variants ◽

Cost Effective Method ◽

Wide Range ◽

Lactamase Gene ◽

Modified Nucleobases

AbstractAdvances in precision medicine require high-throughput, inexpensive, point-of-care diagnostic methods with multi-omics capability for detecting a wide range of biomolecules and their molecular variants. Optical techniques have offered many promising advances towards such diagnostics. However, the inability to squeeze light with several hundred-nanometer wavelengths into angstrom-scale volume for single nucleotide measurements has hindered further progress. Recently, a block optical sequencing (BOS) method has been shown for determining relative nucleobase content in DNA k-mer blocks with Raman spectroscopy, and a block optical content scoring (BOCS) algorithm was developed for robust content-based genetic biomarker database searching. Here, we performed BOS measurements on positively-charged silver nanoparticles to achieve 93.3% accuracy for predicting nucleobase content in DNA k-mer blocks (where k=10), as well as measurements on RNA and chemically-modified nucleobases for extensions to transcriptomic and epigenetic studies. Our high-accuracy BOS measurements were then used with BOCS to correctly identify a β-lactamase gene from the MEGARes antibiotic resistance database and confirm the Pseudomonas aeruginosa pathogen of origin from <12 content measurements (<15% coverage) of the gene. These results prove the integration of BOS/BOCS as a diagnostic optical sequencing platform. With the versatile range of available plasmonic substrates offering simple data acquisition, varying resolution (single-molecule to ensemble), and multiplexing, this optical sequencing platform has potential as the rapid, cost-effective method needed for broad-spectrum biomarker detection.

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A Simple Colorimetric Molecular Detection of Novel Coronavirus (COVID-19), an Essential Diagnostic Tool for Pandemic Screening

10.1101/2020.04.10.20060293 ◽

2020 ◽

Cited By ~ 3

Author(s):

Pazhanimuthu Annamalai ◽

Madhu Kanta ◽

Pazhanivel Ramu ◽

Baskar Ravi ◽

Kokilavani Veerapandian ◽

...

Keyword(s):

Molecular Detection ◽

Point Of Care ◽

Lamp Assay ◽

High Sensitivity ◽

Cost Effective ◽

Cost Effective Method ◽

Recent Outbreak ◽

Pcr Method ◽

Novel Coronavirus ◽

Virus Isolates

AbstractThe recent outbreak of the newly emerged novel coronavirus (SARS-CoV-2) presents a big challenge for public health laboratories as virus isolates are not available while there is an increasing evidence that the epidemic is more widespread than initially thought, as well as spreading internationally across borders through travellers does already happen warranting a methodology for the rapid detection of the infection to control SARS-CoV-2. Aim: We intended to develop and deploy a robust and rapid diagnostic methodology using LAMP assay for use in point of care settings to detect SARS-COV-2 infection. Methodology: In the present study, we have developed a validated rapid diagnostic procedure to detect SARS-CoV-2 using LAMP assay, its design relying on isothermal amplification of the nucleic acids of the SARS-CoV-2. Results: The LAMP assay developed detects SARS-CoV-2 infection rapidly with high sensitivity and reliability. The data generated by LAMP assay were comparable and at par with the data generated by real-time PCR method. Conclusion: The present study demonstrates that the LAMP assay developed was a rapid, reliable, sensitive and cost effective method to detect SARS-CoV-2 infection in a point of care as well as in laboratory settings.

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Clinical performance of two EUA-approved anti-COVID-19 IgG/IgM rapid lateral flow immunoassays using whole blood finger-sticks

10.1101/2021.06.04.21258189 ◽

2021 ◽

Author(s):

Christian Tagwerker ◽

Irfan Baig ◽

Eric Brunson ◽

Kristine Mundo ◽

Dava Dutra-Smith ◽

...

Keyword(s):

Blood Plasma ◽

Whole Blood ◽

Clinical Performance ◽

Point Of Care ◽

Cost Effective ◽

Lateral Flow ◽

Simultaneous Application ◽

Igm Elisa ◽

Elisa Testing ◽

Finger Stick

Serological, or antibody, tests detect immunoglobulins produced by the hosts plasma B cells following exposure to foreign antigens. Venipuncture blood draws to collect human venous whole blood, plasma from anticoagulated blood (Li+ heparin, K2EDTA and sodium citrate), or serum are commonly utilized and require refrigerated temperatures during transport to the testing facility. Subsequent laboratory testing by enzyme-linked immunosorbent assays (ELISA) or chemiluminescence immunoassays (CLIA) can take an additional 2-5 hours. In the context of the COVID-19 pandemic, rapid diagnostic tests (RDT) to be used in point-of-care (POC) and remote settings have become essential during mandatory quarantine and isolation periods. RDTs allowed for more cost-effective testing using less collection materials with an immediate (5-10 minutes) test result. However, the majority of emerging RDTs receiving Emergency Use Authorization (EUA) approval by the Food and Drug Administration (FDA) for qualitative detection and differentiation of IgM and IgG antibodies to SARS-CoV-2 were only approved for use in human venous whole blood, plasma or serum. In this study we summarize performance characteristics of one RDT (COVID-19 IgG/IgM lateral flow immunoassay rapid cassette) to another by simultaneous application of whole blood finger-stick specimens (n = 32). The study was performed over 5 different days, with daily quality controls consisting of serum previously verified to be positive or negative by COVID-19 IgG/IgM ELISA testing.

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Eco-Friendly Synthesis of SnO2-Cu Nanocomposites and Evaluation of Their Peroxidase Mimetic Activity

Nanomaterials ◽

10.3390/nano11071798 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1798

Author(s):

Ravi Mani Tripathi ◽

Sang J. Chung

Keyword(s):

Ph Value ◽

Point Of Care ◽

Low Cost ◽

Colorimetric Detection ◽

Cost Effective ◽

Promising Alternative ◽

Enzyme Mimetic ◽

Peroxidase Mimetic ◽

Point Of Care Diagnostics ◽

Cost Effective Method

The enzyme mimetic activity of nanomaterials has been applied in colorimetric assays and point-of-care diagnostics. Several nanomaterials have been exploited for their peroxidase mimetic activity toward 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide. However, an efficient nanomaterial for the rapid and strong oxidation of TMB remains a strategic challenge. Therefore, in this study, we developed copper-loaded tin oxide (SnO2-Cu) nanocomposites that rapidly oxidize TMB. These nanocomposites have strong absorption at 650 nm and can be used for highly sensitive colorimetric detection. An environmentally friendly (green), rapid, easy, and cost-effective method was developed for the synthesis of these nanocomposites, which were characterized using ultraviolet-visible, energy-dispersive X-ray, and Fourier-transform infrared spectroscopy, as well as scanning electron microscopy. This is the first green synthesis of SnO2-Cu nanocomposites. Their enzyme mimetic activity, which was first studied here, was found to be strongly dependent on the temperature and pH value of the solution. The synthesized nanocomposites have the advantages of low cost, high stability, and ease of preparation for enzyme mimetic applications. Hence, SnO2-Cu nanocomposites are a promising alternative to peroxidase enzymes in colorimetric point-of-care diagnostics.

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Using off – set handpumps — a cost-effective method to protect drinking water in rural villages

Waterlines ◽

10.3362/0262-8104.1984.019 ◽

1984 ◽

Vol 2 (4) ◽

pp. 25-26

Author(s):

Daniel Jenkins

Keyword(s):

Drinking Water ◽

Cost Effective ◽

Rural Villages ◽

Cost Effective Method

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CAD Of Anticorrosive Protection Of Steel Structures

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2019.09.18-23 ◽

2019 ◽

pp. 18-23

Keyword(s):

Protective Coating ◽

Computer Aided Design ◽

Steel Structures ◽

Cost Effective ◽

Operating Conditions ◽

Computational Tool ◽

Protection Method ◽

Cost Effective Method ◽

The Cost ◽

Aided Design

The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.

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Monitoring effluent quality in hypertrophic wastewater reservoirs using remote sensing

Water Science & Technology ◽

10.2166/wst.1996.0148 ◽

1996 ◽

Vol 33 (8) ◽

pp. 23-29 ◽

Cited By ~ 3

Author(s):

I. Dor ◽

N. Ben-Yosef

Keyword(s):

Water Quality ◽

Theoretical Model ◽

Principal Component ◽

Cost Effective ◽

Operational Parameters ◽

Effluent Quality ◽

Optical Images ◽

Routine Monitoring ◽

Cost Effective Method ◽

Wastewater Quality

About one hundred and fifty wastewater reservoirs store effluents for irrigation in Israel. Effluent qualities differ according to the inflowing wastewater quality, the degree of pretreatment and the operational parameters. Certain aspects of water quality like concentration of organic matter, suspended solids and chlorophyll are significantly correlated with the water column transparency and colour. Accordingly optical images of the reservoirs obtained from the SPOT satellite demonstrate pronounced differences correlated with the water quality. The analysis of satellite multispectral images is based on a theoretical model. The model calculates, using the radiation transfer equation, the volume reflectance of the water body. Satellite images of 99 reservoirs were analyzed in the chromacity space in order to classify them according to water quality. Principal Component Analysis backed by the theoretical model increases the method sensitivity. Further elaboration of this approach will lead to the establishment of a time and cost effective method for the routine monitoring of these hypertrophic wastewater reservoirs.

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