Advances in Lateral Flow Technology for the Point-of-Care Market

Current technological advances are broadening the diagnostic possibilities for lateral flow platforms

30 Oct 2015
Sonia Nicholas
Managing Editor and Clinical Lead

Editorial article

Lateral flow assays, such as this saliva test for nitric oxide, are a mainstay technological platform in the IVD industry

Lateral flow assays are a well established, cost-effective technology designed to detect target analytes in a sample. Lateral flow immunoassays, also known as immunochromatography assays, are simple assays that all use the same basic principle.

Each assay typically consists of a sample pad, on to which the test sample is applied; a conjugate pad containing the target analyte conjugated to coloured particles (usually gold nanoparticles or latex spheres); the reaction membrane, on to which a line of anti-target analyte antibodies are attached; and an absorbent waste pad that pulls the sample across the reaction membrane.

Ease of use

Lateral flow immunoassays have the advantage of being easy to use; they can test small sample volumes, they usually have a long shelf-life, they can produce results quickly and can have high specificity and sensitivity.

Disadvantages of lateral flow assays include a difficulty in multiplexing (simultaneous marker analysis), some sensitivity issues and challenges in test-to-test reproducibility.

The assays are relatively low cost to produce and have a short timeline for test development and market approval. As a result, they are a popular platform of choice for developers of rapid disease diagnostics. These rapid diagnostic tests may be used by laboratory personnel, but often the ultimate goal is to move the testing outside of the laboratory, to the point-of-care.

Recent advances

Advances are being made in the application of lateral flow assays to multiplex testing. In September 2015, SCIENION AG and Axxin Pty Ltd announced a partnership to collaborate. The alliance brings together SCIENION's picoliter dispensing technology and Axxin's experience in commercializing diagnostic instrument systems for point-of-care diagnostics. Initial beta testing of the new platform has proved promising and the product in development will be capable of analyzing up to 20 parameters for infectious diseases, drugs of abuse and allergies.

It is even possible to screen for myeloma now using lateral flow technology. Abingdon Health markets a rapid diagnostic device called Seralite® that uses monoclonal antibodies conjugated to gold particles, incorporated into a hand-held lateral flow device. The platform is able to provide a quantitative measurement of kappa and lambda free light chains to support the diagnosis and monitoring of myeloma.

As the demand for more sensitive and faster assays increases, lateral flow developers have increasingly sophisticated technology at their disposal. Anteo Techologies produces a 200nm Coupling Kit that makes conducting lateral flow tests and biomolecule separation easier and more flexible. Anteo Technologies states that magnetic particles are easier to handle than gold particles and that they also have greater sensitivity.

The 200 nm Coupling Kit makes conducting lateral flow tests and biomolecule separation (including cell separation) easier and more flexible

Earlier this year, NanoHybrids announced the release of a new line of spherical gold nanoparticles - the coloured particles conjugated to the target analyte on the conjugate pad. Using a proprietary synthesis method, these gold nanoparticles are produced at a 10-15x higher concentration as compared to traditional protocols. NanoHybrids claims that the new monodisperse gold particles enable the development of assays that reach the highest specifications with regards to sensitivity and reproducibility.

Aptamers are also gaining increasing attention for use in lateral flow tests. They have an almost unlimited shelf-life, they can be selected to bind difficult targets and they allow for very well-defined, single-site conjugation chemistries. Download this application note from Base Pair Technologies to learn more.

Lateral flow assays are a mainstay of the in vitro diagnostics rapid testing industry. Recent advances are helping to really optimize these tests for use in the point-of-care market.

Image credit: "Saliva test for nitric oxide" by Teststrips - Photo of test strips in my home. Licensed under CC BY-SA 3.0 via Wikipedia - https://en.wikipedia.org/wiki/File:Saliva_test_for_nitric_oxide.jpg#/media/File:Saliva_test_for_nitric_oxide.jpg

AMG™ Coupling Kit, 200 nm Magnetic Particles

Anteo Technologies

The 200 nm Coupling Kit makes conducting lateral flow tests and biomolecule separation (including cell separation) easier and more flexible. The Kit contains Mix&Go™ activated 200 nm magnetic particles that give you increased antibody binding capacity and functionality, while the included blocking buffer decreases background noise. Reduce reagent preparation time; remove traditional surface preparation steps such as EDC and replace these steps with the 200 nm pre-activated magnetic particles provided. This Kit reduces aggregation and gives you the freedom and ability to produce multifunctional particles for diverse applications, including dual labelling. For lateral flow tests, magnetic particles are easier to handle than gold. Magnetic separation removes the need to perform centrifugation and filtration concentration. At Anteo, we have also seen greater sensitivity using magnetic particles instead of gold during lateral flow tests. This 200 nm Kit gives you a higher binding capacity than the AMG™ Coupling Kit, 1µm Magnetic particles per mass of particles, potentially leading to a higher yield.   Features & Benefits: Easier and more flexible lateral flow tests Easier and more flexible biomolecule separation For diverse applications, including dual labelling Increase antibody functionality Reduce reagent preparation time by 3-4 hours Highly monodispersed Low background noise Kit reduces aggregation High reproducibility between experiments Applications: Particle Based Immunoassays Lateral Flow Bioseparations and Immunoprecipitation Kit components: Activated 200 nm Magnetic Particles Coupling Buffer Blocking Buffer Storage Buffer Low Binding Microcentrifuge Tubes Sizes: 10 Reactions 30 Reactions

(0)

Links

Tags

HematologyIn Haematology / Hematology, complete blood cell counts (or full blood counts) are obtained using automated blood count analyzers to enumerate blood cell types.  Hematology also encompasses haemostasis and coagulation, thrombophilia and hemophilia, plasma viscosity and ESR analysis, hemoglobinopathies, cell morphology and haematinic measurement.ImmunologyImmunological techniques measure and characterize immune responses. Immunology kits and analysis systems often use techniques such as ELISA, radioimmunoassay (RIA) and immunodiffusion assays, Immunohistochemistry, and flow cytometry. Immunologists use equipment such as flow Cytometers, plate readers, plate washers and fluorescent microscopes.Cell-Based AssaysCell-based assays are used to monitor the presence, quantity and activities of a desired cellular analyte including drug molecules or biomarkers. This can reveal information on cell health (apoptosis, cytotoxicity, viability and proliferation assays), cell metabolism, cell migration and cell signaling mechanisms. Find the best cell-based assay products, kits and equipment with our peer reviewed product directory: compare products, check customer reviews and receiving pricing direct from manufacturers.Point-of-CarePoint-of-Care Testing (POCT) or Near Patient Testing (NPT) products are available for urine, blood and other clinical chemistry analyses. POCT includes: blood glucose testing, blood gas and electrolytes analysis, rapid coagulation testing (PT / INR), rapid cardiac markers diagnostics, drugs of abuse screening, urine strips testing, pregnancy testing, fecal occult blood analysis, food pathogens screening, hemoglobin diagnostics, infectious disease testing and cholesterol screening.Clinical ChemistryBiochemistry (or clinical chemistry) involves the analysis of bodily fluids using chemical tests. Techniques used include HPLC, chromatography, spectroscopy, mass spectrometry, immunochemical, electrophoresis, turbidometric / spectrophotometric assay, MRI and ISE analysis. Tests are often carried out on plasma or serum but urine (urinalysis) and fecal specimens are also processed.Clinical MicrobiologyMicrobiology is the study of microorganisms including protists, prokaryotes, fungi, and, often, viruses. Microorganisms are a useful research tool as genetic vectors and, in immunology, for antibiotic susceptibility testing, cellular biology and genetics. Microorganisms commonly grow readily in incubators with microbial culture media; this can contain chromogenic supplements to differentiate between cell lines. Estimate your culture’s density of microorganisms with colony counters, or screen and select colonies for desirable clones with automated colony pickers. Additionally, equipment is available to monitor environments for the presence of microbes and identify with microbial identification instruments. Find the best microbiology products in our peer-reviewed product directory: compare products, check customer reviews and receive pricing direct from manufacturers.Point of Care SolutionsPoint of care solutions provide medical diagnostics and treatments at or near the site of patient care. These technologies offer rapid results, helping healthcare providers make quick decisions. From glucose monitors to molecular diagnostics, point of care solutions are transforming healthcare delivery by reducing wait times and improving patient outcomes. Explore the best point of care products in our peer-reviewed product directory, compare options, check reviews, and get pricing directly from manufacturers.