Instrument-Free and Visual Detection of Salmonella Based on Magnetic Nanoparticles and an Antibody Probe Immunosensor

Salmonella, a common foodborne pathogen, causes many cases of foodborne illness and poses a threat to public health worldwide. Immunological detection systems can be combined with nanoparticles to develop sensitive and portable detection technologies for timely screening of Salmonella infections. Here, we developed an antibody-probe-based immuno-N-hydroxysuccinimide (NHS) bead (AIB) system to detect Salmonella. After adding the antibody probe, Salmonella accumulated in the samples on the surfaces of the immuno-NHS beads (INBs), forming a sandwich structure (INB–Salmonella–probes). We demonstrated the utility of our AIB diagnostic system for detecting Salmonella in water, milk, and eggs, with a sensitivity of 9 CFU mL−1 in less than 50 min. The AIB diagnostic system exhibits highly specific detection and no cross-reaction with other similar microbial strains. With no specialized equipment or technical requirements, the AIB diagnostic method can be used for visual, rapid, and point-of-care detection of Salmonella.

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Salivary diagnostic biomarker for periodontal disease - A review

Journal of Dental Specialities ◽

10.18231/j.jds.2021.003 ◽

2021 ◽

Vol 9 (1) ◽

pp. 7-12

Author(s):

T Prasanth ◽

Sumita Manandhar ◽

Satisha T S ◽

Pramod Kumar

Keyword(s):

Alveolar Bone ◽

Point Of Care ◽

Low Cost ◽

Complex Mixture ◽

Response To Therapy ◽

Clinical Criteria ◽

Detection Systems ◽

Technological Advances ◽

Tissue Attachment ◽

Point Of Care Detection

Periodontitis is chronic inflammation of the periodontium caused by persistent bacterial infection affecting the connective tissue attachment and supporting bone around the teeth. As the ability to reconstruct the periodontium is limited after alveolar bone loss, early diagnosis and intervention should be paramount goals of periodontal treatment preventing future disease’s progression. Saliva is a physiologic fluid that contains complex mixture of substances as well as inflammatory biomarkers associated with periodontitis. Conventional clinical criteria are often insufficient for determining sites of active disease, for monitoring the response to therapy, or for measuring the degree of susceptibility to future disease progression. Therefore, the use of saliva has provided a substantial addition to the diagnostic armamentarium as an investigative tool for disease processes. With the current technological advances, together with point-of-care detection systems, salivary analysis will be valued much more highly in the near future. Even though saliva is easy to manipulate with low-cost storage, careful attention must be directed to limit variation in specimen integrity. This review focuses on the biomarkers in saliva that appears to be promising in the future for periodontal diagnosis, as well as some contemporary diagnostic tests available.

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Rapid detection of SARS-CoV-2 with CRISPR-Cas12a

PLoS Biology ◽

10.1371/journal.pbio.3000978 ◽

2020 ◽

Vol 18 (12) ◽

pp. e3000978

Author(s):

Dan Xiong ◽

Wenjun Dai ◽

Jiaojiao Gong ◽

Guande Li ◽

Nansong Liu ◽

...

Keyword(s):

Detection Method ◽

Point Of Care ◽

High Sensitivity ◽

Nucleic Acid Detection ◽

Global Pandemic ◽

Portable Detection ◽

Recent Outbreak ◽

Associated Proteins ◽

Specialized Equipment ◽

Viral Diagnosis

The recent outbreak of betacoronavirus Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which is responsible for the Coronavirus Disease 2019 (COVID-19) global pandemic, has created great challenges in viral diagnosis. The existing methods for nucleic acid detection are of high sensitivity and specificity, but the need for complex sample manipulation and expensive machinery slow down the disease detection. Thus, there is an urgent demand to develop a rapid, inexpensive, and sensitive diagnostic test to aid point-of-care viral detection for disease monitoring. In this study, we developed a clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated proteins (Cas) 12a-based diagnostic method that allows the results to be visualized by the naked eye. We also introduced a rapid sample processing method, and when combined with recombinase polymerase amplification (RPA), the sample to result can be achieved in 50 minutes with high sensitivity (1–10 copies per reaction). This accurate and portable detection method holds a great potential for COVID-19 control, especially in areas where specialized equipment is not available.

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Laboratory evaluation of two point-of-care detection systems for early and accurate detectaion of influenza in the Lao People's Democratic Republic

International Journal of Infectious Diseases ◽

10.1016/j.ijid.2020.12.059 ◽

2020 ◽

Author(s):

Wanitchaya Kittikraisak ◽

Bouaphanh Khamphaphongphane ◽

Sinakhone Xayadeth ◽

Virasack Som Oulay ◽

Viengphone Khanthamaly ◽

...

Keyword(s):

Democratic Republic ◽

Point Of Care ◽

Laboratory Evaluation ◽

Lao People’S Democratic Republic ◽

Detection Systems ◽

Lao People's Democratic Republic ◽

Point Of Care Detection

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Rapid, Sensitive, and Accurate Point-of-Care Detection of Lethal Amatoxins in Urine

Toxins ◽

10.3390/toxins12020123 ◽

2020 ◽

Vol 12 (2) ◽

pp. 123 ◽

Cited By ~ 2

Author(s):

Candace S. Bever ◽

Kenneth D. Swanson ◽

Elizabeth I. Hamelin ◽

Michael Filigenzi ◽

Robert H. Poppenga ◽

...

Keyword(s):

Human Urine ◽

Urine Analysis ◽

Point Of Care ◽

Urine Samples ◽

Liquid Chromatography Mass Spectrometry ◽

Medical Assistance ◽

Human Urine Samples ◽

Assistance Dogs ◽

Specialized Equipment ◽

Point Of Care Detection

Globally, mushroom poisonings cause about 100 human deaths each year, with thousands of people requiring medical assistance. Dogs are also susceptible to mushroom poisonings and require medical assistance. Cyclopeptides, and more specifically amanitins (or amatoxins, here), are the mushroom poison that causes the majority of these deaths. Current methods (predominantly chromatographic, as well as antibody-based) of detecting amatoxins are time-consuming and require expensive equipment. In this work, we demonstrate the utility of the lateral flow immunoassay (LFIA) for the rapid detection of amatoxins in urine samples. The LFIA detects as little as 10 ng/mL of α-amanitin (α-AMA) or γ-AMA, and 100 ng/mL of β-AMA in urine matrices. To demonstrate application of this LFIA for urine analysis, this study examined fortified human urine samples and urine collected from exposed dogs. Urine is sampled directly without the need for any pretreatment, detection from urine is completed in 10 min, and the results are read by eye, without the need for specialized equipment. Analysis of both fortified human urine samples and urine samples collected from intoxicated dogs using the LFIA correlated well with liquid chromatography–mass spectrometry (LC-MS) methods.

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Faculty Opinions recommendation of Rapid point-of-care detection of the tuberculosis pathogen using a BlaC-specific fluorogenic probe.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717959009.793462512 ◽

2012 ◽

Author(s):

David Lawrence ◽

Zach Rodgers

Keyword(s):

Point Of Care ◽

Fluorogenic Probe ◽

Point Of Care Detection

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Emerging Options for the Diagnosis of Bacterial Infections and the Characterization of Antimicrobial Resistance

International Journal of Molecular Sciences ◽

10.3390/ijms22010456 ◽

2021 ◽

Vol 22 (1) ◽

pp. 456

Author(s):

Simone Rentschler ◽

Lars Kaiser ◽

Hans-Peter Deigner

Keyword(s):

Antimicrobial Resistance ◽

Bacterial Infections ◽

Point Of Care ◽

Rapid Identification ◽

Adequate Treatment ◽

Resistance Patterns ◽

Detection And Diagnosis ◽

Patient Prognosis ◽

Point Of Care Detection

Precise and rapid identification and characterization of pathogens and antimicrobial resistance patterns are critical for the adequate treatment of infections, which represent an increasing problem in intensive care medicine. The current situation remains far from satisfactory in terms of turnaround times and overall efficacy. Application of an ineffective antimicrobial agent or the unnecessary use of broad-spectrum antibiotics worsens the patient prognosis and further accelerates the generation of resistant mutants. Here, we provide an overview that includes an evaluation and comparison of existing tools used to diagnose bacterial infections, together with a consideration of the underlying molecular principles and technologies. Special emphasis is placed on emerging developments that may lead to significant improvements in point of care detection and diagnosis of multi-resistant pathogens, and new directions that may be used to guide antibiotic therapy.

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Design and experimental investigation of a novel spiral microfluidic chip to separate wide size range of micro-particles aimed at cell separation

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1177/09544119211029753 ◽

2021 ◽

pp. 095441192110297

Author(s):

Seyed Ali Tabatabaei ◽

Mohammad Zabetian Targhi

Keyword(s):

Point Of Care ◽

Diagnostic System ◽

Average Diameter ◽

Microfluidic System ◽

Microfluidic Chips ◽

Medical Sciences ◽

Blood Samples ◽

Micro Particles ◽

Monodisperse Polystyrene ◽

Device Size

Isolation of microparticles and biological cells on microfluidic chips has received considerable attention due to their applications in numerous areas such as medical and engineering fields. Microparticles separation is of great importance in bioassays due to the need for smaller sample and device size and lower manufacturing costs. In this study, we first explain the concepts of separation and microfluidic science along with their applications in the medical sciences, and then, a conceptual design of a novel inertial microfluidic system is proposed and analyzed. The PDMS spiral microfluidic device was fabricated, and its effects on the separation of particles with sizes similar to biological particles were experimentally analyzed. This separation technique can be used to separate cancer cells from the normal ones in the blood samples. These components required for testing were selected, assembled, and finally, a very affordable microfluidic kit was provided. Different experiments were designed, and the results were analyzed using appropriate software and methods. Separator system tests with polydisperse hollow glass particles (diameter 2–20 µm), and monodisperse Polystyrene particles (diameter 5 & 15 µm), and the results exhibit an acceptable chip performance with 86% of efficiency for both monodisperse particles and polydisperse particles. The microchannel collects particles with an average diameter of 15.8, 9.4, and 5.9 μm at the proposed reservoirs. This chip can be integrated into a more extensive point-of-care diagnostic system to test blood samples.

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