Fida Biosystems (Fidabio) offers a new proprietary technology developed for quantification and characterization of proteins and nanoparticles from 0.5 to 1,000 nm Dh, incl. antibodies, liposomes, exosomes, membrane embedded proteins et al. Based on accurate, in-solution, absolute measurements of hydrodynamic radius, the technology provides precise information about Kd, concentration, size, stoichiometry, conformational changes, oligomeric state, immunogenicity, multiple bindings etc. It is characterised by being fast (minutes), requiring very small sample amounts (ul-nl), and being exceptionally tolerant to the sample matrix, incl. plasma, serum, cell lysate, fermentation media etc. Contrary to most other procedures, the methodology is based on binding in homogenous solution; complications related to non-specific surface adsorption and challenging assay development are therefore avoided. I.e. the unique features of the FIDA technology enable characterisation and quantification in native (biorelevant) environments and in-built assay quality control and automation.