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Immunoassay Analyzers

How Immunoassay Analyzers Work & How We Save You Time & Money

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Immunoassay analysis diagram

An immunoassay is a type of biochemical diagnostic test that identifies and quantifies an analyte in a solution by using an antibody or antigen that binds with the specific structure of a molecule as the method of detection.

Clinical diagnostics diagram

An immunoassay analyzer is an automated instrument that uses immunoassay methodologies to produce accurate immunoassay test results using a variety of techniques. Whether you run dozens or hundreds of tests daily, it is a reliable and intuitive device that can help optimize your lab’s performance.

Hospitals and clinical or medical laboratories can use immunoassay analyzers to run automated biochemical tests that detect the presence and concentration of a substance within a sample.

The test is performed using an antibody as a reagent, which is chemically linked with a specific label such as an enzyme. These conjugated labels allow the detection of antibodies and antigens present in a sample. Without labeling, the binding that does occur would not be measurable.

Immunoassay testing is extensively used in scientific research. It’s capabilities include diagnosing infectious disease, targeting cancer, therapeutic drug monitoring, cardiac analysis, allergy testing, as well as protein, bacterial, and toxin determination. The type of immunoassay you use, along with technique and label, depends on the results you wish to obtain.

IA Method, Types of Immunoassays, & Labels Used

An open hand balancing a test tube on the index finger

When choosing an immunoassay analyzer, it is important to consider the type of tests required, which labels must be used, and the potential for automation of a technique.

How It Works

In principle, an immunoassay relies on the binding properties of an antibody in order to obtain results. An antibody, or immunoglobulin, is a large, y-shaped protein that is produced by the immune system in response to the presence of a recognized antigen, also known as an immunogen.

An antigen can be defined as a toxin or foreign substance that elicits an immune response. Antigens may include pathogenic organisms such as bacteria and viruses, as well as proteins, polysaccharides, antibiotics, toxins, and more. It is important to note that not all antigens elicit a response from the immune system. Incomplete antigens, or haptens, must be bound with a larger carrier molecule in order to create a response. Immunogens have distinct surface features which result in specific responses from antibodies.

An antibody will attach itself using two binding sites, or paratopes, to a specific and limited area of the surface on the antigen known as an epitope. This means that one specific type of antibody is capable of recognizing, binding to, and neutralizing another specific type of antigen. This occurrence is also known as an antigen-antibody reaction. Harnessing the binding powers of antibody-antigen interaction makes any immunoassay a powerful diagnostic tool.


Referred to as enzyme immunoassay (EIA) or enzyme-linked immunosorbent assay (ELISA), this technique relies on an enzyme-labeled antibody, rather than radioactivity, to detect and measure bound antibodies and antigens present in a solution. EIA uses the enzyme, such as horseradish peroxidase (HRP) and alkaline phosphatase (AP), as a probe. The probe provides a detectable color change when a substrate or chromogen is applied. A substrate is typically a solid substance or medium that acts as an adhering layer for another substance, in this case, the enzyme. This type of testing is quick, convenient, sensitive, and easy to automate. One drawback to consider is that the enzyme-substrate reaction ends quickly and must be read as soon as possible.


Fluorescence methods include fluoroimmunoassay (FIA), a technique that is comparable to radioimmunoassay (RIA). Rather than using a radioisotope, fluorophores are used to create a measurable signal. Fluorophores, fluorescent chemicals that can re-emit light upon excitation, can include Fluorescein isothiocyanate (FITC) as well as phycoerythrin, a type of red photosynthetic pigment that is present in red algae. This technique is also sensitive, specific, and easy to automate. Multiple labels can be used, which is something to consider when requiring many tests to be performed simultaneously.


Chemiluminescent immunoassay (CLIA) determines the concentration of a sample according to the intensity of luminescence that a chemical reaction emits. CLIA is a variation of EIA, in that it employs the same enzyme-labeled antibodies for detection, but instead applies a luminescent substrate to create a measurable signal. This converts the substrate to a reaction product, emitting a photon of light instead of developing a noticeable color. This technique is highly sensitive, easy to automate, and can be used in a high throughput system. It has a wider dynamic range than other immunoassay methods and, due to its extreme sensitivity, can detect very small amounts of a biological molecule. Its linear relationship between luminosity and the level of concentration also provides reliable results.


Radioimmunoassay (RIA) technology was the first type of testing to be developed, however, it has fallen out of favor due to developments in other immunoassay techniques, its difficulty to perform, and the potential dangers presented when working with any amount of radioactivity. However, it is still widely used as it offers distinct advantages in terms of simplicity and sensitivity. By utilizing radioactive isotopes to label an antibody, RIA can measure the concentration of an analyte as it binds with unlabeled antigens.

Label-Free Methods

Although some types of labels are generally used in immunoassays, there are label-free methods available. These detection methods don’t rely on any modification or labeling to measure the concentration of a sample. These include surface plasmon resonance instruments and quartz crystal microbalances.

Benchtop Immunoassay System Leases to Fit Every Need

An animated test result

Founder-Friendly Leases

Our lease agreements are founder-friendly and flexible, helping you preserve working capital, strengthen the cash flow of your business, and keep business credit lines open for expansions, staffing, and other crucial operational expenses and business development opportunities.

2-5 Year Lease Lengths

Leases range from 2 to 5 years. Length will depend on several factors, including how long you want to use the equipment, equipment type, and your company’s financial position. These are standard factors leasing companies consider and help us tailor a lease agreement to fit your needs.

Your Choice of Manufacturer

We don’t carry an inventory. This means you’re not limited to a specific set of manufacturers. Instead, you can pick the equipment that aligns with your business goals and preferences. We’ll work with the manufacturer of your choice to get the equipment in your facility as quickly as possible.

Maintenance & Repair Coverage

Bundle preventive maintenance and repair coverage with your lease agreement. You can spread those payments over time. Easily maintain your equipment, minimize the chances something will break down, repair instrumentation quickly, and simplify your payment processes.

End-of-Lease Options

At the end of your lease, you have multiple options. You can either renew the lease at a significantly lower price, purchase the machine outright based on the fair market value of the original pricing, or call it a day and we’ll come the pick up the equipment for you free of charge.

No Loan-Like Terms

Our leases do not include loan-like terms, which can be restrictive or harmful in certain situations. We do not require debt covenants, IP pledges, collateral,  or equity participation. Our goal is to maximize your flexibility. When you lease with us, you’re collaborating with a true business partner.

In-House Underwriting Process

Our underwriting is done in-house. You can expect quicker turnaround, allowing you respond to your equipment needs as they arise. We require less documentation than traditional lenders and financiers and can get the equipment you need in operation more quickly.