Rapid Detection of Coronavirus (COVID-19) Using Microwave Immunosensor Cavity Resonator

This paper presents a rapid diagnostic device for the detection of the pandemic coronavirus (COVID-19) using a micro-immunosensor cavity resonator. Coronavirus has been declared an international public health crisis, so it is important to design quick diagnostic methods for the detection of infected cases, especially in rural areas, to limit the spread of the virus. Herein, a proof-of-concept is presented for a portable laboratory device for the detection of the SARS-CoV-2 virus using electromagnetic biosensors. This device is a microwave cavity resonator (MCR) composed of a sensor operating at industrial, scientific and medical (ISM) 2.45 GHz inserted in 3D housing. The changes of electrical properties of measured serum samples after passing the sensor surface are presented. The three change parameters of the sensor are resonating frequency value, amplitude and phase of the reflection coefficient |S11|. This immune-sensor offers a portable, rapid and accurate diagnostic method for the SARS-CoV-2 virus, which can enable on-site diagnosis of infection. Medical validation for the device is performed through biostatistical analysis using the ROC (Receiver Operating Characteristic) method. The predictive accuracy of the device is 63.3% and 60.6% for reflection and phase, respectively. The device has advantages of low cost, low size and weight and rapid response. It does need a trained technician to operate it since a software program operates automatically. The device can be used at ports’ quarantine units, hospitals, etc.

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Low-Cost and Lightweight 3D-Printed Split-Ring Resonator for Chemical Sensing Applications

Sensors ◽

10.3390/s18093049 ◽

2018 ◽

Vol 18 (9) ◽

pp. 3049 ◽

Cited By ~ 8

Author(s):

Ahmed Salim ◽

Saptarshi Ghosh ◽

Sungjoon Lim

Keyword(s):

Chemical Sensing ◽

Ring Resonator ◽

Low Cost ◽

Three Dimensional ◽

External Cavity ◽

Cavity Resonator ◽

Split Ring Resonator ◽

Microwave Cavity ◽

Split Ring ◽

Sensing Applications

In this paper, a microwave cavity resonator is presented for chemical sensing applications. The proposed resonator is comprised of a three dimensional (3D) split-ring resonator (SRR) residing in an external cavity and capacitively coupled by a pair of coaxial probes. 3D-printing technology with polylactic acid (PLA) filament is used to build the 3D SRR and cavity. Then, the surfaces of the SRR and the inside walls of cavity are silver-coated. The novelty of our proposed structure is its light weight and inexpensive design, owing to the utilization of low density and low-cost PLA. A Teflon tube is passed through the split-gap of the SRR so that it is parallel to the applied electric field. With an empty tube, the resonance frequency of the structure is measured at 2.56 GHz with an insertion loss of 13.6 dB and quality factor (Q) of 75. A frequency shift of 205 MHz with respect to the empty channel was measured when deionized water (DIW) was injected into the tube. Using volume occupied by the structure, the weight of the proposed microwave resonator is estimated as 22.8 g which is significantly lighter than any metallic structure of comparable size.

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Performance of Tsol-p27 antigen for the serological diagnosis of cysticercosis in Mozambique

Journal of Helminthology ◽

10.1017/s0022149x15000747 ◽

2015 ◽

Vol 90 (5) ◽

pp. 630-633 ◽

Cited By ~ 2

Author(s):

N. Nhancupe ◽

E.V. Noormahomed ◽

S. Afonso ◽

K.I. Falk ◽

J. Lindh

Keyword(s):

Western Blot ◽

Sensitivity And Specificity ◽

Blot Analysis ◽

Western Blot Analysis ◽

Low Cost ◽

High Sensitivity ◽

Diagnostic Methods ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Neuroimaging Techniques

AbstractThe diagnosis of neurocysticercosis (NCC) requires expensive neuroimaging techniques that are seldom affordable for people in endemic countries. Accordingly, there is a need for new low-cost diagnostic methods that offer high sensitivity and specificity. In this study, we evaluated Western blot analysis of the previously described recombinant antigen Tsol-p27 in relation to a commercial or in-house enzyme-linked immunosorbent assay (ELISA) for NCC, and compared the results with those provided by a commercial enzyme-linked immunoelectrotransfer blot (EITB) assay, which was regarded as the reference standard method. The analysed serum samples were obtained from 165 people, 18 of whom were confirmed to be NCC positive by EITB. Comparing our Western blot analysis of Tsol-p27 with a previous evaluation performed in Central America showed similar specificity (96.69% versus 97.8%) and sensitivity (85.71% versus 86.7%). The present results indicate that the recombinant Tsol-p27 antigen provides good sensitivity and specificity, and might be preferable as a diagnostic antigen in poorly equipped laboratories in endemic countries.

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SPEEDS: A Portable Serological Testing Platform for Rapid Electrochemical Detection of SARS-CoV-2 Antibodies

10.1101/2021.05.16.21256907 ◽

2021 ◽

Author(s):

Ran Peng ◽

Yueyue Pan ◽

Zhijie Li ◽

Zhen Qin ◽

James M. Rini ◽

...

Keyword(s):

Point Of Care ◽

Low Cost ◽

Serum Antibody ◽

Electrochemical Immunosensor ◽

Immunoglobulin M ◽

Serum Samples ◽

Health Crisis ◽

Population Immunity ◽

Stable Performance ◽

Antibody Levels

The COVID-19 pandemic has resulted in a worldwide health crisis. Rapid diagnosis, new therapeutics and effective vaccines will all be required to stop the spread of COVID-19. Quantitative evaluation of serum antibody levels against the SARS-CoV-2 virus provides a means of monitoring a patient's immune response to a natural viral infection or vaccination, as well as evidence of a prior infection. In this paper, a portable and low-cost electrochemical immunosensor is developed for the rapid and accurate quantification of SARS-CoV-2 serum antibodies. The immunosensor is capable of quantifying the concentrations of immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies against the SARS-CoV-2 spike protein in human serum. For IgG and IgM, it provides measurements in the range of 10.1 ng/mL—60 μg/mL and 1.64 ng/mL — 50 μg/mL, respectively, and both antibodies can be assayed in 13 min. We also developed device stabilization and storage strategies to achieve stable performance of the immunosensor within 24-week storage at room temperature. We evaluated the performance of the immunosensor using COVID-19 patient serum samples collected at different time points after symptom onset. The rapid and sensitive detection of IgG and IgM provided by our immunosensor fulfills the need of rapid COVID-19 serology testing for both point-of-care diagnosis and population immunity screening.

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All-Solid-State Potentiometric Ion-Sensors Based on Tailored Imprinted Polymers for Pholcodine Determination

Polymers ◽

10.3390/polym13081192 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1192

Author(s):

Hisham S. M. Abd-Rabboh ◽

Abd El-Galil E. Amr ◽

Abdulrahman A. Almehizia ◽

Ayman H. Kamel

Keyword(s):

Solid State ◽

Low Cost ◽

Cost Effective ◽

Pharmaceutical Formulations ◽

Measurement Sensitivity ◽

Serum Samples ◽

Multiwalled Carbon ◽

Imprinted Polymers ◽

High Measurement ◽

Liquid Chromatographic

In recent times, the application of the use of ion-selective electrodes has expanded in the field of pharmaceutical analyses due to their distinction from other sensors in their high selectivity and low cost of measurement, in addition to their high measurement sensitivity. Cost-effective, reliable, and robust all-solid-state potentiometric selective electrodes were designed, characterized, and successfully used for pholcodine determination. The design of the sensor device was based on the use of a screen-printed electrode modified with multiwalled carbon nanotubes (MWCNTs) as a solid-contact transducer. Tailored pholcodine (PHO) molecularly imprinted polymers (MIPs) were prepared, characterized, and used as sensory receptors in the presented potentiometric sensing devices. The sensors exhibited a sensitivity of 31.6 ± 0.5 mV/decade (n = 5, R2 = 0.9980) over the linear range of 5.5 × 10−6 M with a detection limit of 2.5 × 10−7 M. Real serum samples in addition to pharmaceutical formulations containing PHO were analyzed, and the results were compared with those obtained by the conventional standard liquid chromatographic approach. The presented analytical device showed an outstanding efficiency for fast, direct, and low-cost assessment of pholcodine levels in different matrices.

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Standardization of dot-ELISA for the serological diagnosis of toxocariasis and comparision of the assay with ELISA

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46651992000100010 ◽

1992 ◽

Vol 34 (1) ◽

pp. 55-60 ◽

Cited By ~ 34

Author(s):

Eide Dias Camargo ◽

Paulo Mutuko Nakamura ◽

Adelaide José Vaz ◽

Marcos Vinícius da Silva ◽

Pedro Paulo Chieffi ◽

...

Keyword(s):

Low Cost ◽

Clinical Signs ◽

Toxocara Canis ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Specific Antibodies ◽

Normal Individuals ◽

Before And After ◽

Dot Elisa ◽

Stability Time

The dot-enzyme-linked immunosorbent assay (dot-ELISA) was standardized using somatic (S) and excretory-secretory (ES) antigens of Toxocara-canis for the detection of specific antibodies in 22 serum samples from children aged 1 to 15 years, with clinical signs of toxocariasis. Fourteen serum samples from apparently normal individuals and 28 sera from patients with other pathologies were used as controls. All samples were used before and after absorption with Ascaris suum extract. When the results were evaluated in comparison with ELISA, the two tests were found to have similar sensitivity, but dot-ELISA was found to be more specific in the presence of the two antigens studied. Dot-ELISA proved to be effective for the diagnosis of human toxocariasis, presenting advantages in terms of yield, stability, time and ease of execution and low cost.

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Retrospective analysis of hospital morbidity with uveitis

Modern technologies in ophtalmology ◽

10.25276/2312-4911-2021-2-116-120 ◽

2021 ◽

pp. 116-120

Author(s):

S.A. Amansakhatov ◽

◽

A.P. Yalkabova ◽

Keyword(s):

Retrospective Analysis ◽

Rural Areas ◽

Urine Analysis ◽

Age Groups ◽

Posterior Uveitis ◽

Diagnostic Methods ◽

Ophthalmological Examination ◽

Case Histories ◽

Infectious Uveitis ◽

Hospital Morbidity

Purpose. To study the structure of hospital incidence of uveitis on the basis of a retrospective analysis of case histories of the International Center for Eye Diseases. Material and мethods. A retrospective analysis of the case histories of 896 patients with various forms of uveitis for 10 years (from 2011 to 2020) was carried out. Standard ophthalmological examination: visiometry, refractometry, tonometry, biomicroscopy, ophthalmoscopy,USB, OCT. Laboratory examination: general blood and urine analysis, biochemical and immunological blood tests. Results. The hospital incidence of uveitis was 6.5% with a slight predominance of females (53.3%) and a predominance of people living in rural areas (62.4%). Clinically and anatomically, the most common in the age groups from 31 to 60 years was the most common anterior uveitis 39.4% (n=353), followed by posterior uveitis in frequency – 38.3% (n=343), average uveitis – 7.9% (n=71) and panuveitis 2.2% (n=20). Unilateral lesion in 68.9% of patients. The etiological factor was established in 29.3% of patients, of which the largest group was infectious uveitis – 20.6% of cases. Most often, herpesvirus and cytomegalovirus were infectious agents (91.4%). Conclusion. The results of the study showed the need for expanding diagnostic methods, correcting the treatment strategy and tactics of managing this category of patients. Key words: uveitis, clinical features, morbidity.

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Green Communication Infrastructure (GCI) Serving Different Smart City Applications

Current Chinese Computer Science ◽

10.2174/2665997201666211119101556 ◽

2021 ◽

Vol 01 ◽

Author(s):

Qutaiba I. Ali ◽

Issam Jafar

Keyword(s):

Rural Areas ◽

Smart City ◽

Low Cost ◽

System Level ◽

Green Communication ◽

Communication Infrastructure ◽

Wide Range ◽

The World ◽

Self Powered ◽

Application Fields

Aims: The aim of the Green Communication Infrastructure ‎‎(GCI) project is to understand the idea of a self ‎‎"sustainably" controlled correspondence foundation ‎fitting for smart city application fields. ‎ Background: This paper shows the endeavors to understand the idea of a ‎self "sustainably" energized communication foundation ‎fitting for smart city application fields. The recommended ‎Green Communication Infrastructure (CGI) comprises ‎different kinds of remote settled (or even versatile) hubs ‎performing diverse activities as per the application ‎requests. An imperative class of these hubs is the Wireless ‎Solar Router (WSR). Objective: The work in this venture was begun in 2009 with the aim ‎of demonstrating the essential advances that must be taken to ‎accomplish such framework and to proclaim the value of ‎embracing natural vitality assets in building mission ‎basic frameworks. Alternate destinations of this venture ‎are introducing a sensibly cost, solid, verified, and simple ‎to introduce correspondence foundation.‎ Method: The arrangement to actualize the GCI was accomplished ‎subsequent to passing two structure levels: device level and ‎system level. Result: The suggested system is highly applicable and serves a wide ‎range of smart city application fields and hence many ‎people and organizations can utilize this system. ‎ Conclusion: The presence of a reliable, secured, low cost, easy to install ‎and self-powered communication infrastructure is ‎mandatory in our nowadays. The communities in ‎developing countries or in rural areas need such a system ‎highly in order to communicate with other people in the ‎world which will affect positively their social and ‎economic situation.

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Social housing for urban households sheltering children responsible for the "kuluna" and "black babies" phenomena in Congo Brazzaville.

Advances in Social Sciences Research Journal ◽

10.14738/assrj.712.9541 ◽

2021 ◽

Vol 7 (12) ◽

pp. 424-437

Author(s):

Alain Symphorien Ndongo

Keyword(s):

Rural Areas ◽

Social Order ◽

Social Housing ◽

Spiritual Development ◽

Deviant Behavior ◽

Low Cost ◽

Urban Housing ◽

The Government ◽

Family Warmth ◽

Congo Brazzaville

Housing as a place where household members spend about half (12 hours) of their daily time, including six to eight hours in sleep, is one of the essential conditions in the fight against poverty and precariousness. The current Congolese urban environment is facing serious problems: small plots of land, lack of suitable housing in relation to the size and composition of households, overcrowding, and water and electricity supplies. This situation is becoming critical with the appearance of deviant behavior among children aged between 10 and 30. The government and its development partners have demonstrated their powerlessness face to this situation, leaving thousands of children on the streets without education or family warmth to form real criminal gangs. These street children have created the phenomena of "kuluna" and "black babies". It has been shown that these one act in this way for their survival, claiming their rights. In this study, we find innovative proposals to provide households sheltering adulterine and adoptive children with low-cost social housing, in order to restore the image of the head of the household and provide the children with a pleasant space for their physical, economic, cultural and spiritual development. This will undoubtedly help to find solutions to the problems facing children and indeed Congolese society as a whole today. The study revealed that if the government does not take practical measures in response to the phenomena created by wayward children, especially "black babies" and "kuluna", there will be a massive adherence of other children, especially the adulterine and adoptive ones. There will be a risk of the phenomena will to be exported to rural areas. The study recommends a "State - Household" partnership in the manufacture of new types of urban housing for households housing children likely to integrate or create gangs, jeopardizing social order and public security.

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Toxoplasmosis serology: an efficient hemagglutination procedure to detect IgG and IgM antibodies

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46651989000400012 ◽

1989 ◽

Vol 31 (4) ◽

pp. 279-285 ◽

Cited By ~ 6

Author(s):

M.E. Camargo ◽

Maria Emilia G. Moura ◽

P.G. Leser

Keyword(s):

Simple Procedure ◽

Low Cost ◽

Protein A ◽

Developed Countries ◽

Serum Samples ◽

Serum Dilution ◽

Specific Antibodies ◽

Igm Antibodies ◽

Diagnostic Capability ◽

Acute Toxoplasmosis

In search of an efficient but simple, low cost procedure for the serodiagnosis of Toxoplasmosis, especially suited for routine laboratories facing technical and budget limitations as in less developed countries, the diagnostic capability of Hematoxo® , an hemagglutination test for toxoplasmosis, was evaluated in relation to a battery of tests including IgG- and IgM-immunofluorescence tests, hemagglutination and an IgM-capture enzymatic assay. Detecting a little as 5 I.U. of IgG antitoxoplasma antibodies, Hematoxo® showed a straight agreement as to reactivity and non-reactivity for the 443 non-reactive and the 387 reactive serum samples, included in this study. In 23 cases presenting a serological pattern of acute toxoplasmosis and showing IgM antibodies, Hematoxo® could detect IgM antibodies in 18, indicated by negativation or a significant decrease in titers as a result of treating samples with 2-mercapto-ethanol. However, a neat increase in sensitivity for IgM specific antibodies could be achieved by previously removing IgG from the sample, as demonstrated in a series of acute toxoplasmosis sera. A simple procedure was developed for this purpose, by reconstituting a lyophilized suspension of Protein A - rich Staphylococcus with the lowest serum dilution to be tested. Of low cost and easy to perform, Hematoxo® affords not only a practical qualitative procedure for screening reactors and non-reactors, as in prenatal services, but also quantitative assays that permit to titrate antibodies as well as to identify IgM antibodies.

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