Bio-layer interferometry (BLI) is an optical biosensing technology for real-time monitoring of biomolecular interactions and is widely used to analyze the interaction between two biomolecules. It is based on the principle of interferometry to obtain quantitative binding kinetics and affinity information by measuring the interference pattern of a light beam reflected and propagated across a biological layer.

In the BLI platform, binding between a ligand immobilized on the biosensor tip and an analyte in solution increases the optical thickness of the biosensor tip, resulting in a wavelength shift proportional to the degree of binding. Readings are collected in real-time as the sensor tip is immersed in the analyte solution (also known as "dip and read"), eliminating the need for continuous flow fluids. BLI system allows the use of a variety of sensors to measure different protein-protein interactions, and binding events can be monitored in real-time without the need for supplemental and expensive labeling. Molecular interaction information such as kinetic rate constants, affinity binding constants, and molecule-specific quantitation are the main characterization information that can be inferred from the BLI platform.

BLI instruments typically consist of a light source and optical system, fiber optic probe, sample carrier, and detection and analysis system. The fiber optic probe is a thin optical fiber connecting the light source to the optical system, with biomolecules such as proteins and antibodies immobilized at one end. The other end of the probe is connected to the light source and optical system through a connector that transmits light to the biological layer and collects the reflected light signal. The detection and analysis system are used to record and analyze changes in the interference pattern and typically includes optical sensors, photoelectric diodes, CCD cameras, and so on, which are used to detect the reflected light signals and convert them into electrical signals.

The greatest advantage of BLI technology is that it can provide real-time information on binding dynamics, enabling researchers to instantly observe and analyze the dynamic process of biomolecular interactions. BLI technology is highly sensitive to the binding and dissociation of biomolecules and can detect trace interaction events. In addition, BLI technology allows real-time monitoring with no or little labeling, reducing experimental steps, interferences, and the time to obtain experimental results.

BLI technology has a wide range of applications in life science research and drug discovery, providing quantitative, real-time, and dynamic information about biomolecular interactions. The most common application of BLI technology is the study of protein-protein interactions, including protein-protein binding, protein complex assembly, and dissociation, which is essential for understanding protein functions, signaling, and disease mechanisms. Therefore, this technique is often used in antibody-antigen interactions, molecular interaction dynamics, and cell surface receptor-ligand interactions. In addition, BLI technology is also used to study protein folding and conformational changes, stability, and dynamics, revealing the relationship between protein structure and function, as well as the mechanisms of disease occurrence associated with protein folding.

Amerigo Scientific offers advanced biolayer interferometry instruments as reliable and advanced tools for studying the binding kinetics and affinity of biomolecules in bioscience, drug discovery, and biomedicine research.