Design, simulation, optimization and manufacturing of an enzyme-based microfluidic biosensor has been carried out during this research to measure histamine concentration in a sample. The designed biosensor is composed of a micro-bioreactor to degrade histamine and yield hydrogen peroxide, and a chemical reactor to measure the amount of hydrogen peroxide, using chemiluminescence methods. The geometry of the bioreactor and chemical reactor is developed through comparison and optimization of several different geometries. In theory, the designed sensor can determine histamine concentration in a range of 10M to 1mM under one minute, with a maximum error of 5%. Designed biosensor is built using...