What are the first principles that FIDA is based on?

FIDA is based on 2 principles:  

 Taylor Dispersion Analysis: Taylor Dispersion Analysis, abbreviated as TDA,is a method that relies on microcapillary flow. It consists on injecting nanolitersof a sample pulse into the smooth flow of a buffer liquid. Taylor dispersiondescribes the behaviour of small particles in the flow. As the flow is laminar, the particles will not mix evenly, but instead experience a fluctuating motion.This is due to the combined effects of convection and radial diffusion.

Stokes and Einstein equation is a kinetic theory, which describes relation between molecular movement and diffusion in a liquid. In FIDA it is used to calculate the hydrodynamic radius based on the previous principle.

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