Alkaline phosphatase (ALP) is an important enzyme that is involved in removing phosphate groups from molecules during metabolic processes. This enzyme functions best in alkaline conditions and is found in several tissues throughout the body, including the liver, bones, kidneys, and intestines. ALP plays a key role in bone formation and the transport of metabolites across cell membranes. Because ALP is released into the bloodstream during liver or bone disorders, it is a clinically significant biomarker used to evaluate liver function and bone health. Elevated ALP levels are commonly associated with conditions such as bile duct obstruction, liver disease, and bone disorders including Paget’s disease and osteomalacia.
 
Signosis' ALP assay kit utilizes a chromogenic substrate, p-nitrophenyl phosphate (pNPP), that releases a colored product when it hydrolyzed into pNP by ALP. Under alkaline conditions, pNP becomes yellow and can be measured spectrophotometrically at an absorbance of 405 nm.