Assay Development
Diagnostic approaches to managing West Nile virus
    ASSAY DEVELOPMENT         Figure 1. (click to enlarge) West Nile virus transmission cycle. (Taken from the Public Health Agency of Canada's Web site and reproduced with the permission of the Minister of Public Works and Government Services.) Ever since West Nile virus (WNV)-related cases of encephalitis were first reported in New York City in 1999, which resulted in seven deaths, the virus has become endemic to North America. Clinical management of...
Dominating the market
    EDITOR'S PAGE     Since the 1960s immunoassays have contributed enormously to clinical lab medicine. During the past few years, immunoassays of all kinds (e.g., automated, manual, ELISAs, enzyme immunoassays, bead arrays, microarrays) have dominated the IVD market, and have become one of the primary and indispensable tools in diagnosing and monitoring in all areas of medicine. The market potential of immunoassays is now even greater than before. The publication...
Porous adhesive technology for diagnostic applications
    ASSAY DEVELOPMENT       Adhesives Research's porous pressure-sensitive adhesive forms isolated channels to control flow and movement of fluids or gases. Diagnostic assays are indispensable for detecting such compounds as drugs, hormones, enzymes, proteins, antibodies, and infectious agents in biological fluids and tissue samples. Diagnostic device developers are currently considering ways for increasing assay sensitivity while reducing device complexity...
Affinity discrimination to avoid interference in assays
    ASSAY DEVELOPMENT       Any immunodiagnostic assay can suffer from negative test effects, which fall under the rubric of interference. These effects lead to imprecision or can result in false-positive or false-negative outcomes. False negatives represent the worst case for most clinical diagnostic tests. However, it is hard to routinely detect them. Now, though, a new buffer is available that, used instead of traditional assay buffers, enables most interference...
Developing assays to fill unmet needs
    IN PERSON - ONLINE EXPANDED VERSION       Marsha Oenick, PhD, is group director, research and development, at Ortho Clinical Diagnostics (Raritan, NJ). She leads an organization responsible for designing, developing, and delivering new assay/reagent products for the company's clinical laboratory and transfusion medicine product lines. She can be reached at moenick@its.jnj.com. With the introduction of new measurement technologies and sample-handling...
Introduction to biochemicals and chemical reagents
      Hollow fiber bioreactors produce highly concentrated secreted proteins from a variety of mammalian cell types in a cost-effective manner. (Photo courtesy of Harlan Bioproducts for Science) In 1975, Georges Köhler and César Milstein developed a process for creating monoclonal antibodies. This was the beginning of an immunoreagent-driven healthcare technology march of progress that has become a central part of the growing multi-billion-dollar IVD...
Biochemicals and chemical reagents: In this section
      1. Biochemical substrates, enzymes, enzyme cofactors are used in diagnostic reagents in which small-molecule analytes, serum enzymes, and similar substances are being measured. Enzyme substrates are also used to amplify the signal measured by an immunoassay analyzer. 2. Controls, calibrators, normal and disease-state sera are used in virtually all assays to ensure the repro­ducibility, accuracy, and specificity of results. 3. General chemicals, buffers,...
Filters, membranes, and bioseparation equipment: In this section
      1. Centrifuge design has remained unchanged for many years. There is only so much that can be done to a spinning rotor placed in a box. There is a wide range of machines available covering every imaginable tube size and maximum spin speed. 2. Chromatography equipment is constantly being updated and refined. New techniques and improvements in software and use are constantly being made. The key is to determine exactly what you require and then find a system that does...
Introduction to assay system components
      Each assay system component contributes to every aspect of the essence of an IVD kit. (Photo courtesy Response Biomedical) While the 1990s may have been the true brink of the point-of-care (POC) era, the new millennium may be the era of mergers and acquisitions. Regardless, modern IVD technologies have changed over the last two decades at a rapid pace akin to the other technology sectors and the pharmaceutical industry. The big lab continues to get bigger, and...
Assay system components: In this section
      1. Custom-molded disposables include holders for lateral-flow immunoassay devices, cuvettes for particular instruments, and specialized sample-handling devices. 2. Dishes, microwell plates, cuvettes are used as containers in assay procedures. Dishes are used for growing bacteria, microwell plates for EIA and for growing cells. Cuvettes are the containers used with spectrophoto­metric and fluorometric analyzers. 3. Instrument housings, and custom-molded...