How Bio-Layer Interferometers Work & How We Save You Time & Money

Excedr - Bio-Layer Interferometers

Regardless of configuration, the Excedr lease program can accommodate your lab’s instrument needs and model preferences. Get in touch with us to learn how leasing can save you time and money on your bio-layer interferometry technology.

All equipment brands/models are available

The Advantages of Excedr’s Biolayer Interferometer Leasing Program:

  • Eliminates the upfront cost of purchasing equipment by spreading its cost over time
  • Minimizes equipment downtime with included complete repair coverage and preventive maintenance
  • Takes advantage of potentially 100% tax deductible* payments, providing you significant cash-savings
  • Expedites the administrative work needed for instrument procurement and logistics
  • Conserves working capital,  enabling you to reinvest in your core business and operations (staffing, inventory, marketing/sales, etc.)
  • Accommodates all manufacturer and model preferences

*Please consult your tax advisor to determine the full tax implications of leasing equipment.

a cell, a microplate well, antibodies, and a dot with 6 lines through it

Bio-layer interferometry, or BLI, is an optical analytical technique that observes the associative and dissociative interaction of molecules.

In chemistry, it is important to know the affinity, thermodynamic properties, and stoichiometry of a substance, or analyte. BLI provides this data by observing and measuring biomolecular interactions, particularly protein interactions, in vitro. It is an important tool in a wide variety of fields.

Using white light, BLI looks at how molecules bind to or disengage from other molecules. Because it is also a label-free technique, it does not use any isotopes that would chemically bind to and label proteins. These features make BLI highly useful for applications such as fragment screening, kinetic characterization, and real-time label-free chemical binding measurements. It is considered a strong alternative to Surface Plasmon Resonance (SPR), however, in comparison, it does have its advantages and disadvantages.

Bio-Layer Interferometer Applications, Benefits, & Costs

an outstretched hand face up holding the end of a DNA double helix

In order to measure biomolecular interactions, BLI shines white light through a biosensor tip. In many cases, a Streptavidin (SA) biosensor is used. However, the biosensor tips available are customizable and vary in use based on the molecule being immobilized and characterized.

The sensor tip has two surfaces inside of it: an internal reference layer and a layer of immobilized proteins on the sensor tip. As the proteins interact with the sample, some molecules will bind to them. Molecular immobilization occurs through the utilization of the high affinity streptavidin-biotin interaction. The biological molecules—in this case, proteins—can be biotinylated using established protocols and immobilized onto the biosensor surface for assay development. In other words, biotin is attached to the protein in order to make detection of the protein possible. The high sensitivity and stable baseline of these biosensor tips supports both kinetic and quantitation experiments.

The more molecules—or ligands—that bind to the immobilized protein, the more interference will occur with the light as it interacts with it. The resulting reflected light’s wavelength will then be shifted. This shifted wavelength is then compared to the reference wavelength. The molecules that are bound or dissociating from the biosensor are the source of the interference pattern. 

Other factors such as unbound molecules, changes in flow rate, and the refractive index of the surrounding medium do not have the same effect. Because of this, the resulting data from BLI can give great insight into a substance’s kinetics, quantitation, affinity, and molecular interactions.

Let’s look at some of the applications and benefits BLI offers.

Study of Kinetics

In chemistry, kinetics is the study of the rate that chemical processes occur. It is also called reaction kinetics. Real-time, label-free bio-layer interferometry is a useful tool used to observe these chemical processes. Specifically, binding affinity and rates lend themselves to this specific optical biosensing technique.

BLI’s ability to quickly measure association and dissociation rates, as well as equilibrium dissociation constants, without leaving behind label reagents makes it extremely valuable to the study of kinetics.


Vaccine Research

As populations grow and microbes evolve, fast and reliable vaccine research is becoming more and more important. BLI’s label-free and real-time testing capabilities make them fast and accurate tools for vaccine research. Areas of use for BLI within vaccine research are:

  • Epitome design, characterization, and recognition studies
  • Pathogen diversity and distribution
  • Antibody affinity and development
  • Host immune response characterization, diversity, and distribution studies
  • Nucleic acid and molecular pathogen-host interaction studies
  • Therapeutic and clinical studies

Furthermore, BLI has been used to characterize COVID-19 antibodies using specific capture reagents to immobilize the antibodies specific to the virus.


Analysis of Protein/Liposome Interactions

In drug discovery, development, and screening, knowing the interaction of relevant biomolecules and cell membranes is important. Artificial membrane systems, such as liposomes, are useful in determining these interactions due to their modularity. Their lipid composition, lipid ratio, and vesicle sizes can all be customized.

BLI offers a number of important benefits to studying these interactions. The high throughput samples, being label-free, can be reused with no risk of clogging that is present in other similar techniques.

For example, biosensor-based small molecule fragment screening with BLI is suitable for monitoring interactions between small molecules. This is due to the technology’s ability to distinguish between non-specific and non-ideal interactions. Examining binding profiles and responses leads to a reduced rate in false-positives.


Analysis of Protein/Protein Interactions

For understanding biological processes, protein-protein interaction observations are important. BLI is an accurate label-free optical tool that is being used to look at these interactions.

Although BLI is not affected by changes in the sample’s composition (unlike other methods), it is not as sensitive as those methods. This lack of change in the refractive index due to sample composition, alterations, its relative ease-of-use, and instrumentation flexibility make it a versatile tool for studying these types of interactions.


BLI Development

In 2005, ForteBio introduced its Octet® platform. The company, along with the Octet® platform, would later be acquired by Pall Corporation, then by Sartorius in April of 2020.

The platform was—and is—based on bio-layer interferometry (BLI) technology, and includes a whole set of systems including instruments, biosensors, reagents and assay kits used to support the evaluation of biomolecular interactions in 96- or 384-well microplates. Furthermore, it’s introduction has allowed for real-time, label-free analysis of chemical affinity, binding kinetics, and concentrations.

Since then, BLI has become a robust optical analytical tool that is used in a wide variety of fields. Of particular note are the advances made in the study of HIV-1. Since HIV-1’s discovery, our understanding of it has grown, however, a cure still remains elusive.

Recently, with the help of BLI, scientists have begun to look deeper at how the HIV-1 cells interact with specific envelopes in the body. If fully understood, these interactions could bring us one step closer to a cure that would help millions of people.


We Offer BLI Leases to Fit Every Need

a petri dish with a sample inside

If your lab studies—or plans to study—biochemistry or cell biology, Excedr can lease BLI technology or Surface Plasmon Resonance (SPR) instrumentation. Get the best data analysis possible, save money on upfront costs, and protect your equipment with comprehensive service plans.

Discuss your exact equipment needs in-depth with us by calling +1 888-927-3802 or completing our contact form.

Operating Lease

This off-balance sheet financing structure provides three options at the end of the term. The lessee has the option to return the equipment to the lessor, renew at a discounted rate, or purchase the instrument for the fair market value. Monthly payments are also 100% tax deductible which yields additional monetary savings.


If you recently bought equipment, Excedr can offer you cash for your device and convert your purchase into a long-term rental. This is called a sale leaseback. If you’ve paid for equipment within the last ninety days, we can help you recoup your investment and allow you to make low monthly payments. This also frees up money in your budget rather than tying it down to a fixed asset.

BLI Machine Manufacturers & Models on the Market
Learn More

Octet® Systems, Octet® R2, Octet® R4, Octet® R8, Octet® RH96, Octet® RH16

Gator Bio:
Gator® Pro, Gator® Plus, Gator® Prime


Operating Capital Benefits

Operating Capital Benefits

Excedr's operating lease structure allows you to keep your business credit line open for expansions, staffing, and other operational expenses. Additionally, it strengthens the cash flow of your business and keeps cash reserves free for business development opportunities.

Effects on Credit

Effects on Credit

Leasing / renting provides you with non-dilutive financing and does not hinder your future borrowing ability. You're able to acquire the equipment you need without the baggage associated with traditional financing.

Speed of Approval

Speed of Approval

Excedr's program allows you to respond quickly as your need for equipment and technology arises. You can be approved with minimal documentation and have the equipment you need in operation and generating revenue for your business quickly.

Refurbished Equipment

Refurbished Equipment

Unlike traditional financing and leasing companies, the Excedr program can accommodate refurbished equipment in addition to demo units. If you are looking for additional cost-savings, we recommend considering this option.