Ammonia is an important source of nitrogen for living systems. Nitrogen is required for the synthesis of amino acids, which are the building blocks of protein. Ammonia is a metabolic product which is created through amino acid deamination. It plays an important role in both normal and abnormal animal physiology such as acid/base balance. BioVision provides a rapid, simple, sensitive, and reliable assay suitable for research and high throughput assay of Ammonia. In this non-enzymatic assay, ammonia is used to form indophenol, a highly colored product easily quantifiable by colorimetry (OD670 nm) using a plate reader. The kit can detect less than 1 nmol (~10 μM) ammonia using either a 96 well or 384 well microwell plate.