Ag Nanoparticles with Ultrathin Au Shell-Based Lateral Flow Immunoassay for Colorimetric and SERS Dual-Mode Detection of SARS-CoV-2 IgG

Analytical Chemistry, Год журнала: 2022, Номер 94(23), С. 8466 - 8473

Опубликована: Июнь 3, 2022

Immunoglobulin detection is essential for diagnosing progression of SARS-CoV-2 infection, which IgG one the most important indexes. In this paper, Ag nanoparticles with ultrathin Au shells (∼2 nm) embedded 4-mercaptobenzoic acid (MBA) (AgMBA@Au) were manufactured via a ligand-assisted epitaxial growth method and integrated into lateral flow immunoassay (LFIA) colorimetric SERS dual-mode IgG. AgMBA@Au possessed not only surface chemistry advantages but also superior optical characteristics Ag. Moreover, nanogap between core shell greatly enhanced Raman signal. After being modified anti-human antibodies, recognized combined IgG, was captured by spike protein on T line. Qualitative analysis achieved visually observing color line, quantitative conducted measuring signal sensitivity four orders magnitude higher (detection limit: 0.22 pg/mL). The intra-assay inter-assay variation coefficients 7.7 10.3%, respectively, other proteins at concentrations 10 to 20 times than those could hardly produce distinguishable signals, confirming good reproducibility specificity. Finally, used detect 107 clinical serum samples. results agreed well obtained from enzyme-linked immunosorbent assay kits significantly better colloidal gold test strips. Therefore, LFIA has great potential in practical applications can be screen trace early immune response SARS-CoV-2.

Язык: Английский

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Label-free impedimetric immunosensor for point-of-care detection of COVID-19 antibodies

Microsystems & Nanoengineering, Год журнала: 2023, Номер 9(1)

Опубликована: Янв. 1, 2023

Abstract The COVID-19 pandemic has posed enormous challenges for existing diagnostic tools to detect and monitor pathogens. Therefore, there is a need develop point-of-care (POC) devices perform fast, accurate, accessible methods infections immune responses. Devices most amenable miniaturization suitable POC applications are biosensors based on electrochemical detection. We have developed an impedimetric immunosensor interdigitated microelectrode array (IMA) SARS-CoV-2 antibodies in human serum. Conjugation chemistry was applied functionalize covalently immobilize the spike protein (S-protein) of surface IMA serve as recognition layer specifically bind anti-spike antibodies. Antibodies bound S-proteins result increase capacitance consequent change impedance system. label-free uses non-Faradaic with low nonperturbing AC voltage sensitivity capacitive can be enhanced by simply tuning ionic strength sample solution. device exhibits LOD 0.4 BAU/ml, determined from standard curve using WHO IS anti-SARS-CoV-2 immunoglobulins; this similar corresponding LODs reported all validated established commercial assays, which range 0.41 4.81 BAU/ml. proof-of-concept biosensor been demonstrated sera patients infected within 1 h.

Язык: Английский

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Definition of CRISPR Cas12a Trans-Cleavage Units to Facilitate CRISPR Diagnostics

Frontiers in Microbiology, Год журнала: 2021, Номер 12

Опубликована: Ноя. 29, 2021

The CRISPR diagnostic (CRISPR-Dx) technology that employs the trans-cleavage activities has shown great potential in sensitivity, specificity, convenience, and portability, been recognized as next-generation methods. However, due to lack of standardized definition Cas enzymatic units, it is difficult standardize present CRISPR-Dx systems, which have undoubtedly impeded development industry. To solve problem, we here first systematically optimized reaction systems for Cas12a, then defined its units (transU), believe will be importance interest researchers both molecular industry basic research. Moreover, a simple protocol was provided facilitate step-by-step measurement Cas12a transU, can also act reference transU other proteins.

Язык: Английский

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Modular Label-Free Electrochemical Biosensor Loading Nature-Inspired Peptide toward the Widespread Use of COVID-19 Antibody Tests

ACS Nano, Год журнала: 2022, Номер 16(9), С. 14239 - 14253

Опубликована: Авг. 15, 2022

Limitations of the recognition elements in terms synthesis, cost, availability, and stability have impaired translation biosensors into practical use. Inspired by nature to mimic molecular anti-SARS-CoV-2 S protein antibody (AbS) binding site, we synthesized peptide sequence Asn-Asn-Ala-Thr-Asn-COOH (abbreviated as PEP2003) create COVID-19 screening label-free (LF) based on a carbon electrode, gold nanoparticles (AuNPs), electrochemical impedance spectroscopy. The PEP2003 is easily obtained chemical it can be adsorbed electrodes while maintaining its ability for AbS recognition, further leading sensitivity 3.4-fold higher than full-length protein, which agreement with increase target-to-receptor size ratio. Peptide-loaded LF devices noncovalent immobilization were developed affording fast simple analyses, along modular functionalization. From studies docking, peptide-AbS was found driven hydrogen bonds hydrophobic interactions. Moreover, not amenable denaturation, thus addressing trade-off between scalability, robustness. biosensor preserves 95.1% initial signal 20 days when stored dry at 4 °C. With aid two equations fitted machine learning (ML), method able make 39 biological samples healthy infected groups 100.0% accuracy. By taking advantage peptide-related merits combined advances surface chemistry ML-aided accuracy, this platform promising bring mainstream use toward straightforward, fast, accurate analyses point care, social economic impacts being achieved.

Язык: Английский

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An update on lateral flow immunoassay for the rapid detection of SARS-CoV-2 antibodies

AIMS Microbiology, Год журнала: 2023, Номер 9(2), С. 375 - 401

Опубликована: Янв. 1, 2023

Over the last three years, after outbreak of COVID-19 pandemic, an unprecedented number novel diagnostic tests have been developed. Assays to evaluate immune response SARS-CoV-2 widely considered as part control strategy. The lateral flow immunoassay (LFIA), detect both IgM and IgG against SARS-CoV-2, has studied a point-of-care (POC) test. Compared laboratory tests, LFIAs are faster, cheaper user-friendly, thus available also in areas with low economic resources. Soon onset numerous kits for rapid antibody detection were put on market emergency use authorization. However, since then, scientists tried better define accuracy these their usefulness different contexts. In fact, while during first phase pandemic auxiliary molecular diagnosis COVID-19, successively became tool seroprevalence surveillance address infection policies. When 2021 massive vaccination campaign was implemented worldwide, interest LFIA reemerged due need establish extent longevity immunization vaccinated population priorities guide health policies low-income countries limited access vaccines. Here, we summarize accuracy, advantages limits POC detection, highlighting efforts that made improve this technology over few years.

Язык: Английский

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Construction of Optimal SERS Hotspots Based on Capturing the Spike Receptor-Binding Domain (RBD) of SARS-CoV-2 for Highly Sensitive and Specific Detection by a Fish Model

Analytical Chemistry, Год журнала: 2021, Номер 93(48), С. 16086 - 16095

Опубликована: Ноя. 3, 2021

It is highly challenging to construct the best SERS hotspots for detection of proteins by surface-enhanced Raman spectroscopy (SERS). Using its own characteristics can achieve effect sensitivity and specificity. In this study, we built a fishing mode device detect receptor-binding domain (RBD) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at low concentrations in different environments obtained sensitive signal response. Based on spatial resolution their protein-specific recognition functions, were constructed using aptamers small molecules that specifically bind RBD cooperate with Au nanoparticles (NPs) environment signals beacon molecules. Therefore, two kinds AuNPs modified used device, which recognize form stable hotspot high specificity detection. The presence as 0.625 ng/mL produce good response within 15 min. Meanwhile, an mixed solution various proteins, concentration complex urine blood be 1.25 ng/mL. This provides research basis practical applications protein work.

Язык: Английский

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Optical Immunoassays Methods in Protein Analysis: An Overview

Chemosensors, Год журнала: 2022, Номер 10(8), С. 326 - 326

Опубликована: Авг. 12, 2022

Immunoassays are analytical tools that attract growing research attention in the field of sensors. Among different methods, immunoassays based on optical readout have an important role due to high sensitivity reached past years by instrumentation as well preparation new labels. This review aims give overview term basic concepts and practical examples most used techniques, order help readers choose useful techniques for their analyses. Particular emphasis is dedicated application presented detection SARS-CoV-2 virus.

Язык: Английский

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Smart healthcare: A prospective future medical approach for COVID-19

Journal of the Chinese Medical Association, Год журнала: 2022, Номер 86(2), С. 138 - 146

Опубликована: Окт. 13, 2022

COVID-19 has greatly affected human life for over 3 years. In this review, we focus on smart healthcare solutions that address major requirements coping with the pandemic, including (1) continuous monitoring of severe acute respiratory syndrome coronavirus 2, (2) patient stratification distinct short-term outcomes (eg, mild or diseases) and long-term long COVID), (3) adherence to medication treatments patients COVID-19. Smart often utilizes medical artificial intelligence (AI) cloud computing integrates cutting-edge biological optoelectronic techniques. These are valuable technologies addressing unmet needs in management COVID. By leveraging deep learning/machine learning capabilities big data, AI can perform precise prognosis predictions provide reliable suggestions physicians’ decision-making. Through assistance Internet Medical Things, which encompasses wearable devices, smartphone apps, internet-based drug delivery systems, telemedicine technologies, status cases be continuously monitored medications provided at home without need hospital care. develop into cases, emergency feedback through rapid treatment. possibly prevent development therefore lower burden intensive care units.

Язык: Английский

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Carbon-based biosensors: Next-generation diagnostic tool for target-specific detection of SARS-CoV-2 (COVID-19)

Talanta Open, Год журнала: 2023, Номер 7, С. 100218 - 100218

Опубликована: Апрель 25, 2023

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) was declared a global pandemic in 2020. Having rapidly spread around the globe, with emergence of new variants, there is crucial need to develop diagnostic kits for its rapid detection. Since it validated accuracy and reliability, reverse transcription polymerase chain reaction (RT-PCR) test has been gold standard disease However, despite requirement specialized facilities, reagents, duration PCR run limits usage There thus continuous increase design development rapid, point-of-care (PoC), cost-effective kits. In this review, we discuss potential carbon-based biosensors target-specific detection coronavirus 19 (COVID-19) present an overview investigation within timeframe last four years (2019-2022), which have developed novel platforms using carbon nanomaterial-based approaches viral The discussed offer accurate, strategies COVID-19 healthcare personnel research workers.

Язык: Английский

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Electrochemical Sensors

Опубликована: Окт. 18, 2023

Electrochemical sensors are the devices that continuously monitor functioning of a system by combining an artificially determined layer with electrochemical transducer. modern era make use many characteristics to assess presence or absence physical, chemical, natural barrier. Potentiometric, amperometric, and conductometric probes at forefront have advanced stage commercialization. These found commercial applications in numerous important fields including clinical, industrial, environmental, agricultural research. intriguing due their high detectability, ease testing, low cost. Recent advances nanostructured materials diminution sensor size resulted enhanced sampling, sensitivity, stability, detection time. This chapter introduces sensors, discussing three most prevalent types, current applications, anticipated future developments.

Язык: Английский

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