This lecture covers the kinetics and limitations of immunoassays, focusing on topics such as incubation time in ELISA, Langmuir model for adsorption kinetics, diffusion limitations, and microchannel immunoassays. It discusses the equilibrium surface capture, time constants for adsorption and desorption, and the impact of diffusion on reaction rates. The lecture also explores the use of microfluidic channels to enhance immunoassays, the detection kinetics in Mycartis chip, and background reduction techniques in small channels, including TIRF fluorescence and nanofluidic channels.