Flow injection analysis (FIA) is a simple analytical sample processing technique, based on the injection of a definite volume of liquid sample solution in a continuously flowing unsegmented carrier stream followed by the quantitation of specie of interest It offers many advantages over manual methods of analysis, like: flexibility, simplicity, selectivity, reproducibility, higher sampling rate, rapid start-up and shutdown time and economy. Injection volume, operation timing and dispersion must be carefully controlled to achieve precise results. Consumption of reagents is a serious. problem in certain cases which can be controlled by the introduction of different FIA techniques. Instrumentation of FIA is simple. A simple manifold can be quickly assembled. This technique has numerous areas of applications such as environmental pollution biotechnology, agricultural, pharmaceutical and clinical analysis.