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1.
Microchemical Journal ; : 108323, 2022.
Article in English | ScienceDirect | ID: covidwho-2159561

ABSTRACT

The capabilities of bioanalytical mass spectrometry to (i) detect and differentiate viruses at the peptide level whilst maintaining high sample throughput and (ii) to provide diagnosis and prognosis for infected patients are presented as a tutorial in this work to aid analytical chemists and physicians to gain insights into the possibilities offered by current high-resolution mass spectrometry technology and bioinformatics. From (i) sampling to sample treatment;(ii) Matrix-Assisted Laser Desorption Ionization- to Electrospray Ionization -based mass spectrometry;and (iii) from clustering to peptide sequencing;a detailed step-by-step guide is provided and exemplified using SARS-CoV-2 Spike Y839 variant and the variant of concern SARS-CoV-2 Alpha (B.1.1.7 lineage), Influenza B, and Influenza A subtypes AH1N1pdm09 and AH3N2.

2.
ACS Appl Mater Interfaces ; 14(39): 44713-44723, 2022 Oct 05.
Article in English | MEDLINE | ID: covidwho-2016529

ABSTRACT

Early and reliable detection of an infectious viral disease is critical to accurately monitor outbreaks and to provide individuals and health care professionals the opportunity to treat patients at the early stages of a disease. The accuracy of such information is essential to define appropriate actions to protect the population and to reduce the likelihood of a possible pandemic. Here, we show the fabrication of freestanding laser-induced graphene (FLIG) flakes that are highly sensitive sensors for high-fidelity viral detection. As a case study, we show the detection of SARS-CoV-2 spike proteins. FLIG flakes are nonembedded porous graphene foams ca. 30 µm thick that are generated using laser irradiation of polyimide and can be fabricated in seconds at a low cost. Larger pieces of FLIG were cut forming a cantilever, used as suspended resonators, and characterized for their electromechanics behavior. Thermomechanical analysis showed FLIG stiffness comparable to other porous materials such as boron nitride foam, and electrostatic excitation showed amplification of the vibrations at frequencies in the range of several kilo-hertz. We developed a protocol for aqueous biological sensing by characterizing the wetting dynamic response of the sensor in buffer solution and in water, and devices functionalized with COVID-19 antibodies specifically detected SARS-CoV-2 spike protein binding, while not detecting other viruses such as MS2. The FLIG sensors showed a clear mass-dependent frequency response shift of ∼1 Hz/pg, and low nanomolar concentrations could be detected. Ultimately, the sensors demonstrated an outstanding limit of detection of 2.63 pg, which is equivalent to as few as ∼5000 SARS-CoV-2 viruses. Thus, the FLIG platform technology can be utilized to develop portable and highly accurate sensors, including biological applications where the fast and reliable protein or infectious particle detection is critical.


Subject(s)
COVID-19 , Graphite , COVID-19/diagnosis , Graphite/chemistry , Humans , Lasers , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/analysis , Water
3.
Clin Chim Acta ; 532: 181-187, 2022 Jul 01.
Article in English | MEDLINE | ID: covidwho-1966413

ABSTRACT

BACKGROUND: SARS-CoV-2 is an RNA virus that primarily causes respiratory disease; however, infection of other tissue has been reported. Evaluation of SARS-CoV-2 in tissue specimens may increase understanding of SARS-CoV-2 pathobiology. MATERIALS AND METHODS: A qualitative test for detection of SARS-CoV-2 in formalin-fixed paraffin-embedded (FFPE) tissues was developed and validated using droplet digital PCR (ddPCR), which has a lower limit of detection than reverse transcription (RT)-qPCR. After extraction of total RNA from unstained FFPE tissue, SARS-CoV-2 nucleocapsid (N1, N2) target sequences were amplified and quantified, along with human RPP30 as a control using the Bio-Rad SARS-CoV-2 ddPCR kit. RESULTS: SARS-CoV-2 was detected in all 21 known positive samples and none of the 16 negative samples. As few as approximately 5 viral copies were reliably detected. Since January 2021, many tissue types have been clinically tested. Of the 195 clinical specimens, the positivity rate was 35% with placenta and fetal tissue showing the highest percentage of positive cases. CONCLUSION: This sensitive FFPE-based assay has broad clinical utility with applications as diverse as pregnancy loss and evaluation of liver transplant rejection. This assay will aid in understanding atypical presentations of COVID-19 as well as long-term sequelae.


Subject(s)
COVID-19 , RNA, Viral , Real-Time Polymerase Chain Reaction , SARS-CoV-2 , COVID-19/diagnosis , Formaldehyde , Humans , Paraffin Embedding , RNA, Viral/isolation & purification , SARS-CoV-2/genetics
4.
Foods ; 11(14)2022 Jul 14.
Article in English | MEDLINE | ID: covidwho-1938750

ABSTRACT

In 2019, SARS-CoV-2 was identified as the cause of an easily transmissible disease that was declared as a world pandemic. Foodborne transmission was never reported. However, early studies suggested that food could be involved in SARS-CoV-2 entry in the human gastrointestinal tract leading to possible infection, and highlighting the importance of further studies to inspect possible issues linked to food consumption. In this perspective, this work aimed at monitoring SARS-CoV-2 presence in some food and mains water samples in Northern Italy during the COVID-19 pandemic (2020-2022). A total of 1806 foods, 112 mains water samples, and 580 swabs on meat and dairy product surfaces were analyzed for SARS-CoV-2 RNA detection by Real-time PCR. All the analyzed samples were negative to viral RNA detection with the exception of one vegetable sample. Even if data on foodborne coronavirus transmission suggested a limited importance of this pathway, the impact of the current pandemic in Northern Italy deserved a rigorous investigation to rule out such possibility. Indeed, gaining insight on all SARS-CoV-2 possible transmission pathways, including the foodborne route, seemed of interest to maintain consumers' confidence and trust in food safety, and for the effective management of the current, and future, possible pandemics.

5.
Biosensors (Basel) ; 12(5)2022 Apr 28.
Article in English | MEDLINE | ID: covidwho-1875479

ABSTRACT

Infectious diseases remain a pervasive threat to global and public health, especially in many countries and rural urban areas. The main causes of such severe diseases are the lack of appropriate analytical methods and subsequent treatment strategies due to limited access to centralized and equipped medical centers for detection. Rapid and accurate diagnosis in biomedicine and healthcare is essential for the effective treatment of pathogenic viruses as well as early detection. Plasma-engineered polymers are used worldwide for viral infections in conjunction with molecular detection of biomarkers. Plasma-engineered polymers for biomarker-based viral detection are generally inexpensive and offer great potential. For biomarker-based virus detection, plasma-based polymers appear to be potential biological probes and have been used directly with physiological components to perform highly multiplexed analyses simultaneously. The simultaneous measurement of multiple clinical parameters from the same sample volume is possible using highly multiplexed analysis to detect human viral infections, thereby reducing the time and cost required to collect each data point. This article reviews recent studies on the efficacy of plasma-engineered polymers as a detection method against human pandemic viruses. In this review study, we examine polymer biomarkers, plasma-engineered polymers, highly multiplexed analyses for viral infections, and recent applications of polymer-based biomarkers for virus detection. Finally, we provide an outlook on recent advances in the field of plasma-engineered polymers for biomarker-based virus detection and highly multiplexed analysis.


Subject(s)
Communicable Diseases , Virus Diseases , Viruses , Biomarkers , Communicable Diseases/diagnosis , Humans , Polymers , Virus Diseases/diagnosis
6.
15th IEEE International Conference on Nano/Molecular Medicine and Engineering, NANOMED 2021 ; 2021-November:34-37, 2021.
Article in English | Scopus | ID: covidwho-1874333

ABSTRACT

Viral diagnostic is essential to the fields of medicine and bio-nanotechnology, but such analyses can present some complex analytical challenges. While molecular methods that are mostly used in clinical laboratories, for instance, reverse transcription-polymerase chain reaction (RT-PCR) and antigens tests require long acquisition times, and often provides unreliable results for COVID-19 virus detection, the piezo-based sensors coupled with MEMS have demonstrated a significant role in robust viral detection. In this work, we have designed and simulated a piezoelectric MEMS-based biosensor integrated into a wearable face mask for early detection of the SARS-CoV-2 virus droplets. We systematically investigated the influence of virus droplets in changing the applied stress on the cantilever receptor pit with change in mass when viruses (pathogens) from airborne coughing droplets-nuclei binds with coated antibodies on the sensor's cantilever layer with receptor pit thereby generating electric potential. Additionally, Bio-MEMS sensor results have manifested that it has the ability to detect a single size particle of 1 virion with a diameter ≥100 nm and mass of 1fg in a single cough containing droplet nuclei of radius 0.05μm in a less amount of time. Additionally, we empirically set electrical potential as thresholds parameter for our wearable biosensor embedded in the face mask for public monitoring to detect contagious virus particle droplets. Furthermore, this study presented the prospective use of MEMS-based sensing method to identify and detect other biological (bacteria and toxins) analytes. © 2021 IEEE.

7.
Front Microbiol ; 13: 735363, 2022.
Article in English | MEDLINE | ID: covidwho-1809432

ABSTRACT

Objective: We aimed to evaluate the performance of nanopore amplicon sequencing detection for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in clinical samples. Method: We carried out a single-center, prospective cohort study in a Wuhan hospital and collected a total of 86 clinical samples, including 54 pharyngeal swabs, 31 sputum samples, and 1 fecal sample, from 86 patients with coronavirus disease 2019 (COVID-19) from Feb 20 to May 15, 2020. We performed parallel detection with nanopore-based genome amplification and sequencing (NAS) on the Oxford Nanopore Technologies (ONT) minION platform and routine reverse transcription quantitative polymerase chain reaction (RT-qPCR). In addition, 27 negative control samples were detected using the two methods. The sensitivity and specificity of NAS were evaluated and compared with those of RT-qPCR. Results: The viral read number and reference genome coverage were both significantly different between the two groups of samples, and the latter was a better indicator for SARS-CoV-2 detection. Based on the reference genome coverage, NAS revealed both high sensitivity (96.5%) and specificity (100%) compared with RT-qPCR (80.2 and 96.3%, respectively), although the samples had been stored for half a year before the detection. The total time cost was less than 15 h, which was acceptable compared with that of RT-qPCR (∼2.5 h). In addition, the reference genome coverage of the viral reads was in line with the cycle threshold value of RT-qPCR, indicating that this number could also be used as an indicator of the viral load in a sample. The viral load in sputum might be related to the severity of the infection, particularly in patients within 4 weeks after onset of clinical manifestations, which could be used to evaluate the infection. Conclusion: Our results showed the high sensitivity and specificity of the NAS method for SARS-CoV-2 detection compared with RT-qPCR. The sequencing results were also used as an indicator of the viral load to display the viral dynamics during infection. This study proved the wide application prospect of nanopore sequencing detection for SARS-CoV-2 and may more knowledge about the clinical characteristics of COVID-19.

8.
Pathology ; 54(4): 472-478, 2022 Jun.
Article in English | MEDLINE | ID: covidwho-1796234

ABSTRACT

Diagnostic testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has undergone significant changes over the duration of the pandemic. In early 2020, SARS-CoV-2 specific nucleic acid testing (NAT) protocols were predominantly in-house assays developed based on protocols published in peer reviewed journals. As the pandemic has progressed, there has been an increase in the choice of testing platforms. A proficiency testing program for the detection of SARS-CoV-2 by NAT was provided to assist laboratories in assessing and improving test capabilities in the early stages of the pandemic. This was vital in quality assuring initial in-house assays, later commercially produced assays, and informing the public health response. The Royal College of Pathologists of Australasia Quality Assurance Programs (RCPAQAP) offered three rounds of proficiency testing for SARS-CoV-2 to Australian and New Zealand public and private laboratories in March, May, and November 2020. Each round included a panel of five specimens, consisting of positive (low, medium or high viral loads), inconclusive (technical specimen of selected SARS-CoV-2 specific genes) and negative specimens. Results were received for round 1 from 16, round 2 from 97 and round 3 from 101 participating laboratories. Improvement in the accuracy over time was shown, with the concordance of results in round 1 being 75.0%, in round 2 above 95.0% for all samples except one, and for round 3 above 95.0%. Overall, participants demonstrated high capabilities in detecting SARS-CoV-2, even in samples of low viral load, indicating excellent testing accuracy and therefore providing confidence in Australian and New Zealand public and private laboratories test results.


Subject(s)
COVID-19 , SARS-CoV-2 , Australia , COVID-19/diagnosis , Humans , Laboratories , Public Health , RNA, Viral , SARS-CoV-2/genetics
9.
2021 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting, APS/URSI 2021 ; : 1731-1732, 2021.
Article in English | Scopus | ID: covidwho-1774569

ABSTRACT

Traditional molecular techniques for COVID-19 viral detection are time-consuming and can exhibit a high probability of false negatives. In this work, we present a computational study of COVID-19 detection using plasmonic gold nanoparticles. The resonance wavelength of a COVID-19 virion was recently estimated to be in the near-infrared region. By engineering gold nanospheres to bind with the outer surface of the COVID-19 virus specifically, the resonance frequency can be shifted to the visible range (380 nm-700 nm). Moreover, we show that broadband absorption will emerge in the visible spectrum when the virus is partially covered with gold nanoparticles at a certain percentage. This broadband absorption can be used to guide the development of an efficient and accurate colorimetric plasmon sensor for COVID-19 detection. © 2021 IEEE.

10.
Engineering Materials ; : 47-69, 2022.
Article in English | Scopus | ID: covidwho-1767436

ABSTRACT

The mass testing tactic is among the main strategies to fight a virus pandemic. It allows for an early diagnosis in the initial phase of the disease and reduces disease transmission. In this sense, there is a growing interest in developing devices with high sensitivity, selectivity, and fast detections. With this purpose, nanobiosensors are presented as a promising alternative, produced from nanomaterials with different structures and properties. On biosensing, NMs comprise transduction elements (transducers) associated with biomarkers to recognize and amplify different signals when interacting with biological material. The primary transducers involve optical and electrochemical methods. Gold nanoparticles (AuNPs) and carbon-based, such as graphene, graphene oxide, and carbon nanotube (CNT), make up most NMs used in biosensing. For such application, the use of magnetic nanoparticles (MNPs) and quantum dots (QDs) of different compositions, such as the basis of cadmium and tellurium (CdTe QDs), are also widely studied. In addition to applications in biosensing, nanomaterials can be applied in biomarker immobilization and extraction procedure in standard tests such as RT-PCR and LFIA (ELISA). NMs allow for the improvement of different techniques used in viral detection, presenting diverse and unique solutions for health crisis moments, including for Covid-19. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

11.
Clin Infect Dis ; 74(7): 1141-1150, 2022 04 09.
Article in English | MEDLINE | ID: covidwho-1700667

ABSTRACT

BACKGROUND: Reported coronavirus disease 2019 (COVID-19) cases underestimate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. We conducted a national probability survey of US households to estimate cumulative incidence adjusted for antibody waning. METHODS: From August-December 2020 a random sample of US addresses were mailed a survey and self-collected nasal swabs and dried blood spot cards. One adult household member completed the survey and mail specimens for viral detection and total (immunoglobulin [Ig] A, IgM, IgG) nucleocapsid antibody by a commercial, emergency use authorization-approved antigen capture assay. We estimated cumulative incidence of SARS-CoV-2 adjusted for waning antibodies and calculated reported fraction (RF) and infection fatality ratio (IFR). Differences in seropositivity among demographic, geographic, and clinical subgroups were explored. RESULTS: Among 39 500 sampled households, 4654 respondents provided responses. Cumulative incidence adjusted for waning was 11.9% (95% credible interval [CrI], 10.5%-13.5%) as of 30 October 2020. We estimated 30 332 842 (CrI, 26 703 753-34 335 338) total infections in the US adult population by 30 October 2020. RF was 22.3% and IFR was 0.85% among adults. Black non-Hispanics (Prevalence ratio (PR) 2.2) and Hispanics (PR, 3.1) were more likely than White non-Hispanics to be seropositive. CONCLUSIONS: One in 8 US adults had been infected with SARS-CoV-2 by October 2020; however, few had been accounted for in public health reporting. The COVID-19 pandemic is likely substantially underestimated by reported cases. Disparities in COVID-19 by race observed among reported cases cannot be attributed to differential diagnosis or reporting of infections in population subgroups.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Antibodies, Viral , COVID-19/epidemiology , Humans , Immunoglobulin A , Incidence , Pandemics , United States/epidemiology
12.
Sci Total Environ ; 821: 152790, 2022 May 15.
Article in English | MEDLINE | ID: covidwho-1612001

ABSTRACT

Affordably tracking the transmission of respiratory infectious diseases in urban transport infrastructures can inform individuals about potential exposure to diseases and guide public policymakers to prepare timely responses based on geographical transmission in different areas in the city. Towards that end, we designed and tested a method to detect SARS-CoV-2 RNA in the air filters of public buses, revealing that air filters could be used as passive fabric sensors for the detection of viral presence. We placed and retrieved filters in the existing HVAC systems of public buses to test for the presence of trapped SARS-CoV-2 RNA using phenol-chloroform extraction and RT-qPCR. SARS-CoV-2 RNA was detected in 14% (5/37) of public bus filters tested in Seattle, Washington, from August 2020 to March 2021. These results indicate that this sensing system is feasible and that, if scaled, this method could provide a unique lens into the geographically relevant transmission of SARS-CoV-2 through public transit rider vectors, pooling samples of riders over time in a passive manner without installing any additional systems on transit vehicles.


Subject(s)
Motor Vehicles , RNA, Viral/isolation & purification , SARS-CoV-2 , Transportation , COVID-19 , Environmental Monitoring , Humans , SARS-CoV-2/isolation & purification , Washington
13.
J Biomed Sci ; 29(1): 1, 2022 Jan 04.
Article in English | MEDLINE | ID: covidwho-1605455

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic is an exceptional public health crisis that demands the timely creation of new therapeutics and viral detection. Owing to their high specificity and reliability, monoclonal antibodies (mAbs) have emerged as powerful tools to treat and detect numerous diseases. Hence, many researchers have begun to urgently develop Ab-based kits for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Ab drugs for use as COVID-19 therapeutic agents. The detailed structure of the SARS-CoV-2 spike protein is known, and since this protein is key for viral infection, its receptor-binding domain (RBD) has become a major target for therapeutic Ab development. Because SARS-CoV-2 is an RNA virus with a high mutation rate, especially under the selective pressure of aggressively deployed prophylactic vaccines and neutralizing Abs, the use of Ab cocktails is expected to be an important strategy for effective COVID-19 treatment. Moreover, SARS-CoV-2 infection may stimulate an overactive immune response, resulting in a cytokine storm that drives severe disease progression. Abs to combat cytokine storms have also been under intense development as treatments for COVID-19. In addition to their use as drugs, Abs are currently being utilized in SARS-CoV-2 detection tests, including antigen and immunoglobulin tests. Such Ab-based detection tests are crucial surveillance tools that can be used to prevent the spread of COVID-19. Herein, we highlight some key points regarding mAb-based detection tests and treatments for the COVID-19 pandemic.


Subject(s)
Antibodies, Monoclonal , COVID-19 , SARS-CoV-2/isolation & purification , Antibodies, Monoclonal/therapeutic use , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/diagnosis , COVID-19/drug therapy , Humans , Pandemics , Reproducibility of Results , Spike Glycoprotein, Coronavirus/genetics
14.
Ann Epidemiol ; 67: 81-100, 2022 03.
Article in English | MEDLINE | ID: covidwho-1517026

ABSTRACT

PURPOSE: We describe the design of a longitudinal cohort study to determine SARS-CoV-2 incidence and prevalence among a population-based sample of adults living in six San Francisco Bay Area counties. METHODS: Using an address-based sample, we stratified households by county and by census-tract risk. Risk strata were determined by using regression models to predict infections by geographic area using census-level sociodemographic and health characteristics. We disproportionately sampled high and medium risk strata, which had smaller population sizes, to improve precision of estimates, and calculated a desired sample size of 3400. Participants were primarily recruited by mail and were followed monthly with PCR testing of nasopharyngeal swabs, testing of venous blood samples for antibodies to SARS-CoV-2 spike and nucleocapsid antigens, and testing of the presence of neutralizing antibodies, with completion of questionnaires about socio-demographics and behavior. Estimates of incidence and prevalence will be weighted by county, risk strata and sociodemographic characteristics of non-responders, and will take into account laboratory test performance. RESULTS: We enrolled 3842 adults from August to December 2020, and completed follow-up March 31, 2021. We reached target sample sizes within most strata. CONCLUSIONS: Our stratified random sampling design will allow us to recruit a robust general population cohort of adults to determine the incidence of SARS-CoV-2 infection. Identifying risk strata was unique to the design and will help ensure precise estimates, and high-performance testing for presence of virus and antibodies will enable accurate ascertainment of infections.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Antibodies, Viral , COVID-19/epidemiology , Cohort Studies , Humans , Incidence , Longitudinal Studies , Prevalence , San Francisco/epidemiology
15.
Emerg Microbes Infect ; 10(1): 2090-2097, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1479918

ABSTRACT

Since December 2019, coronavirus disease 2019 (COVID-19) caused by SARS coronavirus 2 (SARS-CoV-2) has spread and threatens public health worldwide. The recurrence of SARS-CoV-2 RNA detection in patients after discharge from hospital signals a risk of transmission from such patients to the community and challenges the current discharge criteria of COVID-19 patients. A wide range of clinical specimens has been used to detect SARS-CoV-2. However, to date, a consensus has not been reached regarding the most appropriate specimens to use for viral RNA detection in assessing COVID-19 patients for discharge. An anal swab sample was proposed as the standard because of prolonged viral detection. In this retrospective longitudinal study of viral RNA detection in 60 confirmed COVID-19 patients, we used saliva, oropharyngeal/nasopharyngeal swab (O/N swab) and anal swab procedures from admission to discharge. The conversion times of saliva and anal swab were longer than that of O/N swab. The conversion time of hyper sensitive-CRP was the shortest and correlated with that of CT scanning and viral detection. Some patients were found to be RNA-positive in saliva while RNA-negative in anal swab while the reverse was true in some other patients, which indicated that false negatives were inevitable if only the anal swab is used for evaluating suitability for discharge. These results indicated that double-checking for viral RNA using multiple and diverse specimens was essential, and saliva could be a candidate to supplement anal swabs to reduce false-negative results and facilitate pandemic control.


Subject(s)
COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , SARS-CoV-2/isolation & purification , Saliva/virology , Adult , Anal Canal/virology , False Negative Reactions , Female , Humans , Male , Middle Aged , Nasopharynx/virology , Oropharynx/virology , Patient Discharge , RNA, Viral/analysis , Retrospective Studies , Young Adult
16.
J Virol Methods ; 297: 114251, 2021 11.
Article in English | MEDLINE | ID: covidwho-1347735

ABSTRACT

Since the rapid onset of the COVID-19 pandemic, its causative virus, Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), continues to spread and increase the number of fatalities. To expedite studies on understanding potential surface transmission of the virus and to aid environmental epidemiological investigations, we developed a rapid viability reverse transcriptase PCR (RV-RT-PCR) method that detects viable (infectious) SARS-CoV-2 from swab samples in <1 day compared to several days required by current gold-standard cell-culture-based methods. The method integrates cell-culture-based viral enrichment in a 96-well plate format with gene-specific RT-PCR-based analysis before and after sample incubation to determine the cycle threshold (CT) difference (ΔCT). An algorithm based on ΔCT ≥ 6 representing ∼ 2-log or more increase in SARS-CoV-2 RNA following enrichment determines the presence of infectious virus. The RV-RT-PCR method with 2-hr viral infection and 9-hr post-infection incubation periods includes ultrafiltration to concentrate virions, resulting in detection of <50 SARS-CoV-2 virions in swab samples in 17 h (for a batch of 12 swabs), compared to days typically required by the cell-culture-based method. The SARS-CoV-2 RV-RT-PCR method may also be useful in clinical sample analysis and antiviral drug testing, and could serve as a model for developing rapid methods for other viruses of concern.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Pandemics , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction
17.
Biosens Bioelectron ; 192: 113497, 2021 Nov 15.
Article in English | MEDLINE | ID: covidwho-1309165

ABSTRACT

The ongoing coronavirus disease 2019 (COVID-19) pandemic continues to threaten public health systems all around the world. In controlling the viral outbreak, early diagnosis of COVID-19 is pivotal. This article describes a novel method of voltammetrically determining severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein with a newly designed sensor involving bovine serum albumin, SARS-CoV-2 spike antibody and a functionalised graphene oxide modified glassy carbon electrode (BSA/AB/f-GO/GCE) or screen-printed electrode (BSA/AB/f-GO/SPE). The oxidation reaction based on the antibody-antigen protein interaction was evaluated as a response to SARS-CoV-2 spike protein at -200 mV and 1430 mV with the BSA/AB/f-GO/SPE and BSA/AB/f-GO/GCE, respectively. The developed sensors, BSA/AB/f-GO/SPE and BSA/AB/f-GO/GCE, could detect 1 ag/mL of virus spike protein in synthetic, saliva and oropharyngeal swab samples in 5 min and 35 min, and both sensors demonstrated a dynamic response to the SARS-CoV-2 spike protein between 1 ag/mL and 10 fg/mL. Real-time polymerase chain reaction (RT-PCR), rapid antigen test and the proposed method were applied to saliva samples. When compared to RT-PCR, it was observed that the developed method had a 92.5% specificity and 93.3% sensitivity. Moreover, BSA/AB/f-GO/SPE sensor achieved 91.7% accuracy compared to 66.7% accuracy of rapid antigen test kit in positive samples. In view of these findings, the developed sensor provides great potential for the diagnosing of COVID-19 in real samples.


Subject(s)
Biosensing Techniques , COVID-19 , Spike Glycoprotein, Coronavirus/analysis , COVID-19/diagnosis , Humans , Sensitivity and Specificity
18.
IEEE Sens J ; 21(16): 17643-17656, 2021 Aug 15.
Article in English | MEDLINE | ID: covidwho-1266283

ABSTRACT

Contagious diseases are the principal cause of mortality, particularly respiratory viruses, a real menace for public health and economic development worldwide. Therefore, timely diagnosis and treatments are the only life-saving strategy to overcome any epidemic and particularly the ongoing prevailing pandemic COVID-19 caused by SARS-CoV-2. A rapid identification, point of care, portable, highly sensitive, stable, and inexpensive device is needed which is exceptionally satisfied by sensor technology. Consequently, the researchers have directed their attention to employing sensors targeting multiple analyses of pathogenic detections across the world. Nanostructured materials (nanoparticles, nanowires, nanobundles, etc.), owing to their unique characteristics such as large surface-to-volume ratio and nanoscale interactions, are widely employed to fabricate facile sensors to meet all the immediate emerging challenges and threats. This review is anticipated to foster researchers in developing advanced nanomaterials-based sensors for the increasing number of COVID-19 cases across the globe. The mechanism of respiratory viral detection by nanomaterials-based sensors has been reported. Moreover, the advantages, disadvantages, and their comparison with conventional sensors are summarized. Furthermore, we have highlighted the challenges and future potential of these sensors for achieving efficient and rapid detection.

19.
Adv Exp Med Biol ; 1318: 403-412, 2021.
Article in English | MEDLINE | ID: covidwho-1222726

ABSTRACT

The diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has ramifications on both an individual level and a public health level. The use of appropriate testing mechanisms is paramount to preventing transmission, along with offering treatment to those who are infected and show appropriate symptomatology. The choice of employing a specific test often relies on laboratory capabilities, including the abilities of the medical technologists, the cost of testing platforms, and the individual quirks of each test. This chapter intends to discuss the relevant issues relating to diagnostic testing for SARS-CoV-2, including specimen types and collection methods, viral detection methods, and serological testing.


Subject(s)
COVID-19 , COVID-19 Testing , Clinical Laboratory Techniques , Diagnostic Tests, Routine , Humans , SARS-CoV-2
20.
Int J Mol Med ; 47(6)2021 06.
Article in English | MEDLINE | ID: covidwho-1181666

ABSTRACT

The Coronavirus Disease 2019 (COVID­19) pandemic has forced the scientific community to rapidly develop highly reliable diagnostic methods in order to effectively and accurately diagnose this pathology, thus limiting the spread of infection. Although the structural and molecular characteristics of the severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) were initially unknown, various diagnostic strategies useful for making a correct diagnosis of COVID­19 have been rapidly developed by private research laboratories and biomedical companies. At present, rapid antigen or antibody tests, immunoenzymatic serological tests and molecular tests based on RT­PCR are the most widely used and validated techniques worldwide. Apart from these conventional methods, other techniques, including isothermal nucleic acid amplification techniques, clusters of regularly interspaced short palindromic repeats/Cas (CRISPR/Cas)­based approaches or digital PCR methods are currently used in research contexts or are awaiting approval for diagnostic use by competent authorities. In order to provide guidance for the correct use of COVID­19 diagnostic tests, the present review describes the diagnostic strategies available which may be used for the diagnosis of COVID­19 infection in both clinical and research settings. In particular, the technical and instrumental characteristics of the diagnostic methods used are described herein. In addition, updated and detailed information about the type of sample, the modality and the timing of use of specific tests are also discussed.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , Animals , Biosensing Techniques/methods , Clustered Regularly Interspaced Short Palindromic Repeats , Humans , Inventions , Microscopy, Electron/methods , Nucleic Acid Amplification Techniques/methods , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Virus Cultivation/methods
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