Registering the Kinetics of Intermolecular Interactions by Low-Coherence Interferometry for the Development of Biomarker Immunoassays for Cardiovascular Diseases

The quantitative monitoring of kinetic parameters for the interaction of biomolecules is demanded in many fields of fundamental and applied research. In this study, some compact biosensor devices, which are characterized by high energy efficiency and provide ultrasensitive real-time registration of changes in the thickness of biomolecular complexes on widely available disposable sensor chips, have been developed on the basis of low-coherence interferometry. These instruments are electrically and optically safe, can be powered and controlled by a laptop USB port, and have passive drift-suppressing thermal insulation. The potentialities of these instruments are demonstrated on the kinetic characterization of antibodies as an example to select the most efficient ones as immunoassays for the brain natriuretic peptide, which is a marker of cardiovascular diseases. The devices and methods developed provide for efficient selection of optimal biorecognizing agents for in vitro diagnosis, targeted nanopreparation delivery, etc.