Rapid and Sensitive Point of Care Detection of MRSA gDNA by Nanoelectrokinetic Sensors

Biosensors have shown great potential in realizing rapid, low cost and portable on-site detection for diseases. This work reports the development of a new bioelectronic sensor called AC electrokinetics-based capacitive (ABC) biosensor, for the detection of genomic DNA (gDNA) of methicillin-resistant Staphylococcus aureus (MRSA). The ABC sensor is based on interdigitated microelectrodes biofunctionalized with oligonucleotide probes. It uses a special AC signal for direct capacitive monitoring of topological change on nanostructured sensor surface, which simultaneously induce dieletrophoretic enrichment of target gDNAs. As a result, rapid and specific detection of gDNA/probe hybridization can be realized with high sensitivity. It requires no signal amplification such as labelling, hybridization chain reaction, or nucleic acid sequence-based amplification. This method involves only simple sample preparation. After optimization of nano-structured sensor surface and signal processing, the ABC sensor demonstrated fast turnaround of results (~10 s detection), excellent sensitivity (a detection limit of 4.7 DNA copies /µL MRSA gDNA) and high specificity, suitable for point of care diagnosis. As a bioelectronic sensor, the developed ABC sensors can be easily adapted for detection of other infectious agents.

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Rapid and Sensitive Point of Care Detection of MRSA Genomic DNA by Nanoelectrokinetic Sensors

Chemosensors ◽

10.3390/chemosensors9050097 ◽

2021 ◽

Vol 9 (5) ◽

pp. 97

Author(s):

Rania Oueslati ◽

Yu Jiang ◽

Jiangang Chen ◽

Jayne Wu

Keyword(s):

Genomic Dna ◽

Point Of Care ◽

Low Cost ◽

High Sensitivity ◽

High Specificity ◽

Hybridization Chain Reaction ◽

Sensor Surface ◽

Ac Electrokinetics ◽

Interdigitated Microelectrodes ◽

Nanostructured Sensor

Biosensors have shown great potential in realizing rapid, low cost, and portable on-site detection for diseases. This work reports the development of a new bioelectronic sensor called AC electrokinetics-based capacitive (ABC) biosensor, for the detection of genomic DNA (gDNA) of methicillin-resistant Staphylococcus aureus (MRSA). The ABC sensor is based on interdigitated microelectrodes biofunctionalized with oligonucleotide probes. It uses a special AC signal for direct capacitive monitoring of topological change on nanostructured sensor surface, which simultaneously induces dielectrophoretic enrichment of target gDNAs. As a result, rapid and specific detection of gDNA/probe hybridization can be realized with high sensitivity. It requires no signal amplification such as labeling, hybridization chain reaction, or nucleic acid sequence-based amplification. This method involves only simple sample preparation. After optimization of nanostructured sensor surface and signal processing, the ABC sensor demonstrated fast turnaround of results (~10 s detection), excellent sensitivity (a detection limit of 4.7 DNA copies/µL MRSA gDNA), and high specificity, suitable for point of care diagnosis. As a bioelectronic sensor, the developed ABC sensors can be easily adapted for detections of other infectious agents.

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Electroanalytical Biosensors for Circulating Tumor DNA Detection—A Brief Review

10.20944/preprints202111.0357.v1 ◽

2021 ◽

Author(s):

Zhijia Peng ◽

Xiaogang Lin ◽

Weiqi Nian ◽

Xiaodong Zheng ◽

Jayne Wu

Keyword(s):

Real Time ◽

Point Of Care ◽

Low Cost ◽

High Sensitivity ◽

High Specificity ◽

Circulating Tumor Dna ◽

Minimal Invasive ◽

Diagnosis And Treatment ◽

Detection Technology ◽

Tumor Dna

Early diagnosis and treatment have always been highly desired in the fight against cancer, and detection of circulating tumor DNA (ctDNA) has recently been touted as highly promising for early cancer screening. Consequently, the detection of ctDNA in liquid biopsy gains much attention in the field of tumor diagnosis and treatment, which has also attracted research interest from the industry. However, traditional gene detection technology is difficult to achieve low cost, real-time and portable measurement of ctDNA. Electroanalytical biosensors have many unique advantages such as high sensitivity, high specificity, low cost and good portability. Therefore, this review aims to discuss the latest development of biosensors for minimal-invasive, rapid, and real-time ctDNA detection. Various ctDNA sensors are reviewed with respect to their choices of receptor probes, detection strategies and figures of merit. Aiming at the portable, real-time and non-destructive characteristics of biosensors, we analyze their development in the Internet of Things, point-of-care testing, big data and big health.

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Integrating high-performing electrochemical transducers in lateral flow assay

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-021-03301-y ◽

2021 ◽

Author(s):

Antonia Perju ◽

Nongnoot Wongkaew

Keyword(s):

High Performance ◽

Point Of Care ◽

Low Cost ◽

High Sensitivity ◽

Lateral Flow ◽

Analytical Performance ◽

Label Free ◽

High Performing ◽

Lateral Flow Assays ◽

Electrochemical Transducers

AbstractLateral flow assays (LFAs) are the best-performing and best-known point-of-care tests worldwide. Over the last decade, they have experienced an increasing interest by researchers towards improving their analytical performance while maintaining their robust assay platform. Commercially, visual and optical detection strategies dominate, but it is especially the research on integrating electrochemical (EC) approaches that may have a chance to significantly improve an LFA’s performance that is needed in order to detect analytes reliably at lower concentrations than currently possible. In fact, EC-LFAs offer advantages in terms of quantitative determination, low-cost, high sensitivity, and even simple, label-free strategies. Here, the various configurations of EC-LFAs published are summarized and critically evaluated. In short, most of them rely on applying conventional transducers, e.g., screen-printed electrode, to ensure reliability of the assay, and additional advances are afforded by the beneficial features of nanomaterials. It is predicted that these will be further implemented in EC-LFAs as high-performance transducers. Considering the low cost of point-of-care devices, it becomes even more important to also identify strategies that efficiently integrate nanomaterials into EC-LFAs in a high-throughput manner while maintaining their favorable analytical performance.

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Loop-Mediated Isothermal Amplification as Point-of-Care Diagnosis for Neglected Parasitic Infections

International Journal of Molecular Sciences ◽

10.3390/ijms21217981 ◽

2020 ◽

Vol 21 (21) ◽

pp. 7981

Author(s):

Catalina Avendaño ◽

Manuel Alfonso Patarroyo

Keyword(s):

Neglected Tropical Diseases ◽

Point Of Care ◽

Low Cost ◽

High Specificity ◽

World Health Organisation ◽

Isothermal Amplification ◽

World Health ◽

Parasitic Infections ◽

River Blindness ◽

Loop Mediated Isothermal Amplification

The World Health Organisation (WHO) has placed twenty diseases into a group known as neglected tropical diseases (NTDs), twelve of them being parasitic diseases: Chagas’ disease, cysticercosis/taeniasis, echinococcosis, food-borne trematodiasis, human African trypanosomiasis (sleeping sickness), leishmaniasis, lymphatic filariasis, onchocerciasis (river blindness), schistosomiasis, soil-transmitted helminthiasis (ascariasis, hookworm, trichuriasis), guinea-worm and scabies. Such diseases affect millions of people in developing countries where one of the main problems concerning the control of these diseases is diagnosis-based due to the most affected areas usually being far from laboratories having suitable infrastructure and/or being equipped with sophisticated equipment. Advances have been made during the last two decades regarding standardising and introducing techniques enabling diagnoses to be made in remote places, i.e., the loop-mediated isothermal amplification (LAMP) technique. This technique’s advantages include being able to perform it using simple equipment, diagnosis made directly in the field, low cost of each test and the technique’s high specificity. Using this technique could thus contribute toward neglected parasite infection (NPI) control and eradication programmes. This review describes the advances made to date regarding LAMP tests, as it has been found that even though several studies have been conducted concerning most NPI, information is scarce for others.

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A fully battery-powered inexpensive spectrophotometric system for high-sensitivity point-of-care analysis on a microfluidic chip

The Analyst ◽

10.1039/c6an00370b ◽

2016 ◽

Vol 141 (12) ◽

pp. 3898-3903 ◽

Cited By ~ 15

Author(s):

Maowei Dou ◽

Juan Lopez ◽

Misael Rios ◽

Oscar Garcia ◽

Chuan Xiao ◽

...

Keyword(s):

Microfluidic Chip ◽

Point Of Care ◽

Low Cost ◽

High Sensitivity ◽

Power Supplies ◽

Low Resource Settings ◽

Low Resource ◽

External Power

A low-cost b̲a̲ttery-powered s̲pectrophotometric s̲ystem (BASS) was developed for high-sensitivity point-of-care analysis in low-resource settings on a microfluidic chip without relying on external power supplies.

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Toward point-of-care diagnostics of Candida auris

10.1101/2020.02.10.20021683 ◽

2020 ◽

Cited By ~ 1

Author(s):

Geoffrey Mulberry ◽

Sudha Chaturvedi ◽

Vishnu Chaturvedi ◽

Brian N. Kim

Keyword(s):

New York ◽

Real Time ◽

Real Time Pcr ◽

Positive Impact ◽

Point Of Care ◽

Low Cost ◽

High Sensitivity ◽

Clinical Samples ◽

Pcr Assay ◽

Candida Auris

AbstractCandida auris is a multidrug-resistant yeast that presents global health threat for the hospitalized patients. Early diagnostic of C. auris is crucial in control, prevention, and treatment. Candida auris is difficult to identify with standard laboratory methods and often can be misidentified leading to inappropriate management. A newly-devised real-time PCR assay played an important role in the ongoing investigation of the C. auris outbreak in New York metropolitan area. The assay can rapidly detect C. auris DNA in surveillance and clinical samples with high sensitivity and specificity, and also useful for confirmation of C. auris cultures. Despite its positive impact, the real-time PCR assay is difficult to deploy at frontline laboratories due to high-complexity set-up and operation. Using a low-cost handheld real-time PCR device, we show that the C. auris can potentially be identified in a low-complexity assay without the need for high-cost equipment. An implementation of low-cost real-time PCR device in hospitals and healthcare facilities is likely to accelerate the diagnosis of C. auris and for control of the global epidemic.

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Recent advances of fluorescent biosensors based on cyclic signal amplification technology in biomedical detection

Journal of Nanobiotechnology ◽

10.1186/s12951-021-01149-z ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Hongke Qu ◽

Chunmei Fan ◽

Mingjian Chen ◽

Xiangyan Zhang ◽

Qijia Yan ◽

...

Keyword(s):

Signal Amplification ◽

Low Cost ◽

Rolling Circle Amplification ◽

High Sensitivity ◽

High Specificity ◽

Detection Methods ◽

Research Progress ◽

Rolling Circle ◽

Displacement Reactions ◽

Short Time

AbstractThe cyclic signal amplification technology has been widely applied for the ultrasensitive detection of many important biomolecules, such as nucleic acids, proteins, enzymes, adenosine triphosphate (ATP), metal ions, exosome, etc. Due to their low content in the complex biological samples, traditional detection methods are insufficient to satisfy the requirements for monitoring those biomolecules. Therefore, effective and sensitive biosensors based on cyclic signal amplification technology are of great significance for the quick and simple diagnosis and treatment of diseases. Fluorescent biosensor based on cyclic signal amplification technology has become a research hotspot due to its simple operation, low cost, short time, high sensitivity and high specificity. This paper introduces several cyclic amplification methods, such as rolling circle amplification (RCA), strand displacement reactions (SDR) and enzyme-assisted amplification (EAA), and summarizes the research progress of using this technology in the detection of different biomolecules in recent years, in order to provide help for the research of more efficient and sensitive detection methods. Graphical Abstract

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Low-Cost and Scalable Platform with Multiplexed Microwell Array Biochip for Rapid Diagnosis of COVID-19

Research ◽

10.34133/2021/2813643 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Yang Wang ◽

Kaiju Li ◽

Gaolian Xu ◽

Chuan Chen ◽

Guiqin Song ◽

...

Keyword(s):

Clinical Trials ◽

Reverse Transcriptase ◽

Low Cost ◽

High Sensitivity ◽

High Specificity ◽

Rapid Diagnosis ◽

Negative Patient ◽

Microwell Array ◽

Custom Made ◽

User Friendly

Sensitive detection of SARS-CoV-2 is of great importance for inhibiting the current pandemic of COVID-19. Here, we report a simple yet efficient platform integrating a portable and low-cost custom-made detector and a novel microwell array biochip for rapid and accurate detection of SARS-CoV-2. The instrument exhibits expedited amplification speed that enables colorimetric read-out within 25 minutes. A polymeric chip with a laser-engraved microwell array was developed to process the reaction between the primers and the respiratory swab RNA extracts, based on reverse transcriptase loop-mediated isothermal amplification (RT-LAMP). To achieve clinically acceptable performance, we synthesized a group of six primers to identify the conserved regions of the ORF1ab gene of SARS-CoV-2. Clinical trials were conducted with 87 PCR-positive and 43 PCR-negative patient samples. The platform demonstrated both high sensitivity (95.40%) and high specificity (95.35%), showing potentials for rapid and user-friendly diagnosis of COVID-19 among many other infectious pathogens.

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PCB-Based Magnetometer as a Platform for Quantification of Lateral-Flow Assays

Sensors ◽

10.3390/s19245433 ◽

2019 ◽

Vol 19 (24) ◽

pp. 5433 ◽

Cited By ~ 3

Author(s):

Mohammad Khodadadi ◽

Long Chang ◽

João R. C. Trabuco ◽

Binh V. Vu ◽

Katerina Kourentzi ◽

...

Keyword(s):

High Precision ◽

Fe3o4 Nanoparticles ◽

Printed Circuit Board ◽

Test Line ◽

Point Of Care ◽

Low Cost ◽

Superparamagnetic Iron Oxide ◽

High Sensitivity ◽

Lateral Flow ◽

Circuit Board

This work presents a proof-of-concept demonstration of a novel inductive transducer, the femtoMag, that can be integrated with a lateral-flow assay (LFA) to provide detection and quantification of molecular biomarkers. The femtoMag transducer is manufactured using a low-cost printed circuit board (PCB) technology and can be controlled by relatively inexpensive electronics. It allows rapid high-precision quantification of the number (or amount) of superparamagnetic nanoparticle reporters along the length of an LFA test strip. It has a detection limit of 10−10 emu, which is equivalent to detecting 4 ng of superparamagnetic iron oxide (Fe3O4) nanoparticles. The femtoMag was used to quantify the hCG pregnancy hormone by quantifying the number of 200 nm magnetic reporters (superparamagnetic Fe3O4 nanoparticles embedded into a polymer matrix) immuno-captured within the test line of the LFA strip. A sensitivity of 100 pg/mL has been demonstrated. Upon further design and control electronics improvements, the sensitivity is projected to be better than 10 pg/mL. Analysis suggests that an average of 109 hCG molecules are needed to specifically bind 107 nanoparticles in the test line. The ratio of the number of hCG molecules in the sample to the number of reporters in the test line increases monotonically from 20 to 500 as the hCG concentration increases from 0.1 ng/mL to 10 ng/mL. The low-cost easy-to-use femtoMag platform offers high-sensitivity/high-precision target analyte quantification and promises to bring state-of-the-art medical diagnostic tests to the point of care.

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Electrochemical Detection and Point-of-Care Testing for Circulating Tumor Cells: Current Techniques and Future Potentials

Sensors ◽

10.3390/s20216073 ◽

2020 ◽

Vol 20 (21) ◽

pp. 6073

Author(s):

Chunyang Lu ◽

Jintao Han ◽

Xiaoyi Sun ◽

Gen Yang

Keyword(s):

Tumor Cells ◽

Circulating Tumor Cells ◽

Electrochemical Method ◽

Point Of Care ◽

Low Cost ◽

High Sensitivity ◽

Point Of Care Testing ◽

Testing Instrument ◽

The Past ◽

Main Target

Circulating tumor cells (CTCs) are tumor cells that escaped from the primary tumor or the metastasis into the blood and they play a major role in the initiation of metastasis and tumor recurrence. Thus, it is widely accepted that CTC is the main target of liquid biopsy. In the past few decades, the separation of CTC based on the electrochemical method has attracted widespread attention due to its convenience, rapidness, low cost, high sensitivity, and no need for complex instruments and equipment. At present, CTC detection is not widely used in the clinic due to various reasons. Point-of-care CTC detection provides us with a possibility, which is sensitive, fast, cheap, and easy to operate. More importantly, the testing instrument is small and portable, and the testing does not require specialized laboratories and specialized clinical examiners. In this review, we summarized the latest developments in the electrochemical-based CTC detection and point-of-care CTC detection, and discussed the challenges and possible trends.

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