Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 17 de 17
Filter
1.
Biosensors (Basel) ; 12(7)2022 Jul 03.
Article in English | MEDLINE | ID: covidwho-1957223

ABSTRACT

In vitro diagnosis (IVD) has become a hot topic in laboratory research and achievement transformation. However, due to the high cost, and time-consuming and complex operation of traditional technologies, some new technologies are being introduced into IVD, to solve the existing problems. As a result, IVD has begun to develop toward point-of-care testing (POCT), a subdivision field of IVD. The pandemic has made governments and health institutions realize the urgency of accelerating the development of POCT. Microfluidic paper-based analytical devices (µPADs), a low-cost, high-efficiency, and easy-to-operate detection platform, have played a significant role in advancing the development of IVD. µPADs are composed of paper as the core material, certain unique substances as reagents for processing the paper, and sensing devices, as auxiliary equipment. The published reviews on the same topic lack a comprehensive and systematic introduction to µPAD classification and research progress in IVD segmentation. In this paper, we first briefly introduce the origin of µPADs and their role in promoting IVD, in the introduction section. Then, processing and detection methods for µPADs are summarized, and the innovative achievements of µPADs in IVD are reviewed. Finally, we discuss and prospect the upgrade and improvement directions of µPADs, in terms of portability, sensitivity, and automation, to help researchers clarify the progress and overcome the difficulties in subsequent µPAD research.


Subject(s)
Microfluidic Analytical Techniques , Paper , Lab-On-A-Chip Devices , Microfluidics , Point-of-Care Testing
2.
Bioengineered ; 13(1): 876-883, 2022 01.
Article in English | MEDLINE | ID: covidwho-1585254

ABSTRACT

This research has developed a method for rapid detection of SARS-CoV-2 N protein on a paper-based microfluidic chip. The chitosan-glutaraldehyde cross-linking method is used to fix the coated antibody, and the sandwich enzyme-linked immunosorbent method is used to achieve the specific detection of the target antigen. The system studied the influence of coating antibody concentration and enzyme-labeled antibody concentration on target antigen detection. According to the average gray value measured under different N protein concentrations, the standard curve of the method was established and the sensitivity was tested, and its linear regression was obtained. The equation is y = 9.8286x+137.6, R2 = 0.9772 > 0.90, which shows a high degree of fit. When the concentration of coating antibody and enzyme-labeled antibody were 1 µg/mL and 2 µg/mL, P > 0.05, the difference was not statistically significant, so the lower concentration of 1 µg/mL was chosen as the coating antibody concentration. The results show that the minimum concentration of N protein that can be detected by this method is 8 µg/mL, and the minimum concentration of coating antibody and enzyme-labeled antibody is 1 µg/mL, which has the characteristics of high sensitivity and good repeatability.


Subject(s)
Antigens, Viral/analysis , COVID-19 Serological Testing/instrumentation , Coronavirus Nucleocapsid Proteins/analysis , Coronavirus Nucleocapsid Proteins/immunology , Lab-On-A-Chip Devices , SARS-CoV-2/chemistry , SARS-CoV-2/immunology , Antibodies, Viral/immunology , Biomedical Engineering , COVID-19/diagnosis , COVID-19/immunology , COVID-19/virology , COVID-19 Serological Testing/methods , COVID-19 Serological Testing/standards , Coronavirus Nucleocapsid Proteins/standards , Enzyme-Linked Immunosorbent Assay/instrumentation , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/standards , Humans , Lab-On-A-Chip Devices/standards , Lab-On-A-Chip Devices/statistics & numerical data , Microchip Analytical Procedures/methods , Microchip Analytical Procedures/standards , Microchip Analytical Procedures/statistics & numerical data , Paper , Phosphoproteins/analysis , Phosphoproteins/immunology , Phosphoproteins/standards
3.
Cancer Radiother ; 25(6-7): 645-647, 2021 Oct.
Article in French | MEDLINE | ID: covidwho-1439911

ABSTRACT

Paper patient file sharing has clearly been identified as a risk behavior for the COVID-19 virus transmission in radiotherapy units. In order to overcome this, the ONCORAD radiotherapy units worked on total dematerialization of the paper patient file, within 3 weeks. The methodology is based on a quality approch. This work has led to a convincing improvement in the management of risks a priori and a smoother patient care workflow.


Subject(s)
COVID-19/prevention & control , Electronic Health Records , Fomites/virology , Health Records, Personal , Paper , Radiation Oncology , COVID-19/transmission , Humans
4.
PLoS One ; 16(9): e0257615, 2021.
Article in English | MEDLINE | ID: covidwho-1435618

ABSTRACT

The World Health Organization (WHO) calls for the development of a rapid, biomarker-based, non-sputum test capable of detecting all forms of tuberculosis (TB) at the point-of-care to enable immediate treatment initiation. Lipoarabinomannan (LAM) is the only WHO-endorsed TB biomarker that can be detected in urine, an easily collected sample matrix. For obtaining optimal sensitivity, we and others have shown that some form of sample pretreatment is necessary to remove background from patient urine samples. A number of systems are paper-based often destined for resource limited settings. Our current work presents incorporation of one such sample pretreatment, proteinase K (ProK) immobilized on paper (IPK) and test its performance in comparison to standard proteinase K (SPK) treatment that involves addition and deactivation at high temperature prior to performing a capture ELISA. Herein, a simple and economical method was developed for using ProK immobilized strips to pretreat urine samples. Simplification and cost reduction of the proposed pretreatment strip were achieved by using Whatman no.1 paper and by minimizing the concentration of ProK (an expensive but necessary reagent) used to pretreat the clinical samples prior to ELISA. To test the applicability of IPK, capture ELISA was carried out on either LAM-spiked urine or the clinical samples after pretreatment with ProK at 400 µg/mL for 30 minutes at room temperature. The optimal conditions and stability of the IPK were tested and validation was performed on a set of 25 previously analyzed archived clinical urine samples with known TB and HIV status. The results of IPK and SPK treated samples were in agreement showing that the urine LAM test currently under development has the potential to reach adult and pediatric patients regardless of HIV status or site of infection, and to facilitate global TB control to improve assay performance and ultimately treatment outcomes.


Subject(s)
Biomarkers/urine , Endopeptidase K/metabolism , Enzyme-Linked Immunosorbent Assay/methods , Tuberculosis/diagnosis , Endopeptidase K/chemistry , Enzyme-Linked Immunosorbent Assay/instrumentation , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Humans , Lipopolysaccharides/urine , Paper , Temperature
6.
Talanta ; 235: 122733, 2021 Dec 01.
Article in English | MEDLINE | ID: covidwho-1322356

ABSTRACT

The microfluidic paper-based analytical devices (µPADs) have grown-up swiftly over the decade due to its low cost, simple fabrication procedure, resource-limitedness, non-toxicity and their environmentally benign nature. The µPADs, also identified as point-of-care devices or health care devices have successfully applied in several fields such as diagnostics, biological, food safety, environmental, electrochemical and most importantly colorimetric/fluorimetric sensors, owing to the attractive passive motions of analyte without any external forces. In recent years, a large number of colorimetric and fluorimetric probes have been reported that can selectively recognize the analytes in µPADs. However, there is no organized review on its structure-activity relationship. In this review, we have focused to summarize the colorimetric and fluorimetric probes utilized in µPADs. This review discuss about the relationships between the structure and functions of various probes as signaling units of the efficient µPADs. The probes including nanomaterials, nanozymes, polymers and organic molecules, their structural activity with regard to sensing performances along with their limit of detection are also discussed. This review is expected to assist readers for better understanding of the sensing mechanisms of various chemo and bio-probes utilized in µPADs, as well as promote their advancement in the field. On the other hand, this review also helps the researchers for enhancement of µPADs and paves way for synergistic application of existing molecular probes as an effective diagnostic tool for the worldwide pandemic novel corona virus COVID-19.


Subject(s)
COVID-19 , Microfluidic Analytical Techniques , Humans , Lab-On-A-Chip Devices , Microfluidics , Paper , SARS-CoV-2
7.
J Am Chem Soc ; 143(24): 8957-8961, 2021 06 23.
Article in English | MEDLINE | ID: covidwho-1263458

ABSTRACT

Isothermal amplification strategies capable of rapid, inexpensive, and accurate nucleic acid detection provide new options for large-scale pathogen detection, disease diagnosis, and genotyping. Here we report a highly sensitive multicomponent XNA-based nucleic acid detection platform that combines analyte preamplification with X10-23-mediated catalysis to detect the viral pathogen responsible for COVID-19. The platform, termed RNA-Encoded Viral Nucleic Acid Analyte Reporter (REVEALR), functions with a detection limit of ≤20 aM (∼10 copies/µL) using conventional fluorescence and paper-based lateral flow readout modalities. With a total assay time of 1 h, REVEALR provides a convenient nucleic acid alternative to equivalent CRISPR-based approaches, which have become popular methods for SARS-CoV-2 detection. The assay shows no cross-reactivity for other in vitro transcribed respiratory viral RNAs and functions with perfect accuracy against COVID-19 patient-derived clinical samples.


Subject(s)
COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , DNA, Catalytic/chemistry , RNA, Viral/analysis , SARS-CoV-2/chemistry , Animals , COVID-19 Nucleic Acid Testing/instrumentation , Chlorocebus aethiops , Female , Humans , Limit of Detection , Male , Nasopharynx/virology , Nucleic Acid Amplification Techniques , Oligodeoxyribonucleotides/chemistry , Paper , Sensitivity and Specificity , Vero Cells
8.
BMC Anesthesiol ; 21(1): 115, 2021 04 14.
Article in English | MEDLINE | ID: covidwho-1182027

ABSTRACT

BACKGROUND: The current coronavirus infectious disease 2019 (COVID-19) pandemic has caused unexpected pressure on medical supplies, interrupting supply chains and increasing prices. The supply of antiviral filters which form an essential part of the ventilator circuit have been affected by these issues. Three-dimensional (3D) printing may provide a solution to some of these issues. METHODS: We designed and tested 3D printed heat and moisture exchange (HME) and antiviral casing. For each casing we tested two different filter materials derived from a sediment water filter cartridge or 1.5-µm glass fiber filter paper. A polyurethane sponge was used for the HME. Each design was tested for circuit leak, circuit compliance, peak inspiratory pressure and casing integrity using methylene blue dye. RESULTS: We designed, produced, and tested two different types of antiviral filters with six different internal configurations. Overall, we tested 10 modified filter designs and compared them with the original commercial filter. Except for the combination of 1.5-µm filter paper and 5 mm sponge peak inspiratory pressure and circuit compliance of the filters produced were within the operating limits of the ventilator. All In addition, all filters passed the dye test. CONCLUSIONS: Our filter may be of particular importance to those working in low middle-income countries unable to compete with stronger economies. Our design relies on products available outside the healthcare supply chain, much of which can be purchased in grocery stores, hardware stores, or industrial and academic institutions. We hope that these HMEs and viral filters may be beneficial to clinicians who face critical supply chain issues during the COVID-19 pandemic.


Subject(s)
Printing, Three-Dimensional , Ultrafiltration/instrumentation , Ventilators, Mechanical , Viruses , COVID-19/therapy , Coloring Agents , Equipment Design , Feasibility Studies , Humans , Pandemics , Paper , Peak Expiratory Flow Rate , Polyurethanes , Reproducibility of Results , Surgical Sponges
9.
Biosensors (Basel) ; 11(4)2021 Apr 07.
Article in English | MEDLINE | ID: covidwho-1178107

ABSTRACT

This review summarizes the state of the art of paper-based biosensors (PBBs) for coronavirus disease 2019 (COVID-19) detection. Three categories of PBB are currently being been used for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnostics, namely for viral gene, viral antigen and antibody detection. The characteristics, the analytical performance, the advantages and drawbacks of each type of biosensor are highlighted and compared with traditional methods. It is hoped that this review will be useful for scientists for the development of novel PBB platforms with enhanced performance for helping to contain the COVID-19 outbreak, by allowing early diagnosis at the point of care (POC).


Subject(s)
Biosensing Techniques/methods , COVID-19/diagnosis , Paper , Antigens, Viral/analysis , Biosensing Techniques/instrumentation , COVID-19/virology , CRISPR-Cas Systems/genetics , Humans , Immunoassay , Point-of-Care Systems , RNA, Viral/analysis , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , SARS-CoV-2/metabolism
10.
Med Hypotheses ; 146: 110429, 2021 Jan.
Article in English | MEDLINE | ID: covidwho-1065478

ABSTRACT

The Covid-19 coronavirus, SARS-CoV-2, is inactivated much faster on paper (3 h) than on plastic (7 d). By classifying materials according to virus stability on their surface, the following list is obtained (from long to short stability): polypropylene (mask), plastic, glass, stainless steel, pig skin, cardboard, banknote, cotton, wood, paper, tissue, copper. These observations and other studies suggest that SARS-CoV-2 may be inactivated by dryness on water absorbent porous materials but sheltered by long-persisting micro-droplets of water on waterproof surfaces. If such physical phenomenons were confirmed by direct evidence, the persistence of the virus on any surface could be predicted, and new porous objects could be designed to eliminate the virus faster.


Subject(s)
COVID-19/virology , Fomites/virology , Models, Biological , Paper , Plastics , SARS-CoV-2/physiology , Adsorption , Animals , COVID-19/transmission , Dehydration , Humans , Humidity , In Vitro Techniques , Plastics/chemistry , Porosity , SARS-CoV-2/isolation & purification , SARS-CoV-2/pathogenicity , Surface Properties , Swine , Virus Inactivation , Water
11.
Biosens Bioelectron ; 176: 112912, 2021 Mar 15.
Article in English | MEDLINE | ID: covidwho-987148

ABSTRACT

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is emerging as a global pandemic outbreak. To date, approximately one million deaths and over 32 million cases have been reported. This ongoing pandemic urgently requires an accurate testing device that can be used in the field in a fast manner. Serological assays to detect antibodies have been proven to be a great complement to the standard method of reverse transcription-polymerase chain reaction (RT-PCR), particularly after the second week of infection. We have developed a specific and sensitive immunosensor for immunoglobulin detection produced against SARS-CoV-2. Unlike other lateral flow-based assays (LFAs) involving the utilization of multiple antibodies, we have reported a label-free paper-based electrochemical platform targeting SARS-CoV-2 antibodies without the specific requirement of an antibody. The presence of SARS-CoV-2 antibodies will interrupt the redox conversion of the redox indicator, resulting in a decreased current response. This electrochemical sensor was proven effective in real clinical sera from patients with satisfactory results. In addition, the proposed format was also extended to antigen detection (the spike protein of SARS-CoV-2), which presents new possibilities for diagnosing COVID-19.


Subject(s)
Biosensing Techniques/instrumentation , COVID-19 Serological Testing/instrumentation , COVID-19/diagnosis , SARS-CoV-2/immunology , Antibodies, Viral/analysis , Antigens, Viral/analysis , Biosensing Techniques/methods , COVID-19/immunology , COVID-19/virology , COVID-19 Serological Testing/methods , Cross Reactions , Electrochemical Techniques/instrumentation , Electrochemical Techniques/methods , Equipment Design , Humans , Pandemics , Paper , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/analysis , Spike Glycoprotein, Coronavirus/immunology
12.
Biosens Bioelectron ; 177: 112672, 2021 Apr 01.
Article in English | MEDLINE | ID: covidwho-844839

ABSTRACT

Accurate, rapid, and low-cost molecular diagnostics is essential in managing outbreaks of infectious diseases, such as the pandemic of coronavirus disease 2019 (COVID-19). Accordingly, microfluidic paper-based analytical devices (µPADs) have emerged as promising diagnostic tools. Among the extensive efforts to improve the performance and usability of diagnostic tools, biosensing mechanisms based on electrochemical impedance spectroscopy (EIS) have shown great promise because of their label-free operation and high sensitivity. However, the method to improve EIS biosensing on µPADs is less explored. Here, we present an experimental approach to enhancing the performance of paper-based EIS biosensors featuring zinc oxide nanowires (ZnO NWs) directly grown on working electrodes (WEs). Through a comparison of different EIS settings and an examination of ZnO-NW effects on EIS measurements, we show that ZnO-NW-enhanced WEs function reliably with Faradaic processes utilizing iron-based electron mediators. We calibrate paper-based EIS biosensors with different morphologies of ZnO NWs and achieve a low limit of detection (0.4 pg ml-1) in detecting p24 antigen as a marker for human immunodeficiency virus (HIV). Through microscopic imaging and electrochemical characterization, we reveal that the morphological and the electrochemical surface areas of ZnO-NW-enhanced WEs indicate the sensitivities and sensing ranges of the EIS nanobiosensors. Finally, we report that the EIS nanobiosensors are capable of differentiating the concentrations (blank, 10 ng ml-1, 100 ng ml-1, and 1 µg ml-1) of IgG antibody (CR3022) to SARS-CoV-2 in human serum samples, demonstrating the efficacy of these devices for COVID-19 diagnosis. This work provides a methodology for the rational design of high-performance EIS µPADs and has the potential to facilitate diagnosis in pandemics.


Subject(s)
Biosensing Techniques/instrumentation , COVID-19 Serological Testing/instrumentation , COVID-19/diagnosis , Dielectric Spectroscopy/instrumentation , SARS-CoV-2/isolation & purification , Biosensing Techniques/methods , COVID-19/blood , COVID-19 Serological Testing/methods , Dielectric Spectroscopy/methods , Equipment Design , Humans , Lab-On-A-Chip Devices , Limit of Detection , Nanowires/chemistry , Paper , Zinc Oxide/chemistry
14.
Analyst ; 145(23): 7680-7686, 2020 Nov 23.
Article in English | MEDLINE | ID: covidwho-798256

ABSTRACT

This work reports the development of a rapid, simple and inexpensive colorimetric paper-based assay for the detection of the severe acute respiratory symptom coronavirus 2 (SARS-CoV-2) humanized antibody. The paper device was prepared with lamination for easy sample handling and coated with the recombinant SARS-CoV-2 nucleocapsid antigen. This assay employed a colorimetric reaction, which is followed by horseradish peroxidase (HRP) conjugated detecting antibody in the presence of the 3,3',5,5'-tetramethylbenzidine (TMB) substrate. The colorimetric readout was evaluated and quantified for specificity and sensitivity. The characterization of this assay includes determining the linear regression curve, the limit of detection (LOD), the repeatability, and testing complex biological samples. We found that the LOD of the assay was 9.00 ng µL-1 (0.112 IU mL-1). The relative standard deviation was approximately 10% for a sample number of n = 3. We believe that our proof-of-concept assay has the potential to be developed for clinical screening of the SARS-CoV-2 humanized antibody as a tool to confirm infected active cases or to confirm SARS-CoV-2 immune cases during the process of vaccine development.


Subject(s)
Antibodies, Monoclonal, Humanized/blood , Antibodies, Viral/blood , COVID-19 Testing/methods , Colorimetry/methods , Enzyme-Linked Immunosorbent Assay/methods , Paper , SARS-CoV-2/immunology , Antibodies, Monoclonal, Humanized/immunology , Antibodies, Viral/immunology , Armoracia/enzymology , Benzidines/chemistry , COVID-19/diagnosis , COVID-19 Testing/instrumentation , Colorimetry/instrumentation , Coronavirus Nucleocapsid Proteins/immunology , Enzyme-Linked Immunosorbent Assay/instrumentation , Horseradish Peroxidase/chemistry , Humans , Limit of Detection , Phosphoproteins/immunology , Proof of Concept Study , SARS-CoV-2/chemistry
15.
Analyst ; 145(17): 5725-5732, 2020 Aug 24.
Article in English | MEDLINE | ID: covidwho-663353

ABSTRACT

The SARS-CoV-2 virus is known as the causal agent for the current COVID-19 global pandemic. The majority of COVID-19 patients develop acute respiratory distress syndrome (ARDS), while some experience a cytokine storm effect, which is considered as one of the leading causes of patient mortality. Lipids are known to be involved in the various stages of the lifecycle of a virus functioning as receptors or co-receptors that controls viral propagation inside the host cell. Therefore, lipid-related metabolomics aims to provide insight into the immune response of the novel coronavirus. Our study has focused on determination of the potential metabolomic biomarkers utilizing a Teslin® Substrate in paper spray mass spectrometry (PS-MS) for the development of a rapid detection test within 60 seconds of analysis time. In this study, results were correlated with PCR tests to reflect that the systemic responses of the cells were affected by the COVID-19 virus.


Subject(s)
Coronavirus Infections/pathology , Lipid Metabolism/physiology , Mass Spectrometry/methods , Pneumonia, Viral/pathology , Betacoronavirus/isolation & purification , Biomarkers/metabolism , COVID-19 , Coronavirus Infections/metabolism , Coronavirus Infections/virology , Discriminant Analysis , Humans , Lipids/analysis , Nasopharynx/virology , Pandemics , Paper , Pneumonia, Viral/metabolism , Pneumonia, Viral/virology , SARS-CoV-2
16.
PLoS One ; 15(6): e0234232, 2020.
Article in English | MEDLINE | ID: covidwho-596043

ABSTRACT

Following the fast spread of Covid-19 across Europe and North America in March 2020, many people started stockpiling commodities like toilet paper. Despite the high relevance for public authorities to adequately address stockpiling behavior, empirical studies on the psychological underpinnings of toilet paper stockpiling are still scarce. In this study, we investigated the relation between personality traits, perceived threat of Covid-19, and stockpiling of toilet paper in an online survey (N = 996) across 22 countries. Results suggest that people who felt more threatened by Covid-19 stockpiled more toilet paper. Further, a predisposition towards Emotionality predicted the perceived threat of Covid-19 and affected stockpiling behavior indirectly. Finally, Conscientiousness was related to toilet paper stockpiling, such that individuals higher in Conscientiousness tended to stockpile more toilet paper. These results emphasize the importance of clear communication by public authorities acknowledging anxiety and, at the same time, transmitting a sense of control.


Subject(s)
Coronavirus Infections/psychology , Hoarding , Models, Psychological , Personality , Pneumonia, Viral/psychology , Adult , Bathroom Equipment , COVID-19 , Consumer Behavior , Europe , Female , Humans , Hygiene , Male , North America , Pandemics , Paper , Personality Tests
17.
In Vivo ; 34(3 Suppl): 1637-1644, 2020 Jun.
Article in English | MEDLINE | ID: covidwho-541808

ABSTRACT

BACKGROUND: Sneezes produce many pathogen-containing micro-droplets with high velocities of 4.5-50.0 m/s. Face masks are believed to protect people from infection by blocking those droplets. However, current filtration efficiency tests can't evaluate masks under sneeze-like pressure. The goal of this study was to establish a method to evaluate the filtration efficiency of mask materials under extreme conditions. MATERIALS AND METHODS: Efficiency of surgical masks, gauze masks, gauze, cotton, silk, linen and tissue paper on blocking micro-droplet sized starch particles (average 8.2 µm) and latex microspheres (0.75 µm) with a velocity of 44.4 m/s created by centrifugation was qualitatively analyzed by using imaging-based analysis. RESULTS: The 4 layers of silk could block 93.8% of microspheres and 88.9% of starch particles, followed by the gauze mask (78.5% of microspheres and 90.4% of starch particles) and the 2 layers of cotton (74.6% of microspheres and 87.5-89.0% of particles). Other materials also blocked 53.2-66.5% of microspheres and 76.4%-87.9% of particles except the 8 layers of gauze which only blocked 36.7% of particles. The filtration efficiency was improved by the increased layers of materials. CONCLUSION: Centrifugation-based filtration efficiency test not only compensates shortcomings of current tests for masks, but also offers a simple way to explore new mask materials during pandemics. Common mask materials can potentially provide protection against respiratory droplet transmission.


Subject(s)
Centrifugation/methods , Infection Control/instrumentation , Masks , Materials Testing/methods , Sneezing , Filtration , Humans , Hydrophobic and Hydrophilic Interactions , Microspheres , Paper , Particle Size , Particulate Matter , Pressure , Static Electricity , Textiles
SELECTION OF CITATIONS
SEARCH DETAIL