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BAP (Bone Alkaline Phosphatase)

Analyte: Bone Alkaline Phosphatase

Specimen Type: Serum

Optimum Volume: 0.5 mL


2-8°C -20°C -70°C
5 days 1 year 3 years

Reporting units: U/L

Method: ELISA

Biological or Clinical Significance:

Bone is constantly undergoing a metabolic process called remodeling. This includes a degradation process, bone resorption, mediated by the action of osteoclasts and a building process, bone formation, mediated by osteoblasts. Remodeling is required for the maintenance and overall health of bone and is tightly coupled; that is, resorption and formation are in balance.

Skeletal or bone-specific alkaline phosphatase (BAP) is a tetrameric glycoprotein found on the cell surfaces of osteoblasts. As an indicator of osteoblastic activity, BAP provides information on bone formation. As a quantitative measure of bone turnover, BAP provides useful information on bone remodeling in osteoporosis and Paget's disease.

Principle of Test Method:

The BAP assay is a solid-phase ELISA that employs the quantitative enzymatic immunoassay principle.


1. Greenspan, S.L., Dresner-Pollak, R., Parker, R.A., London, D., Ferguson, L., “Diurnal Variation of Bone Mineral Turnover in Elderly Men and Women,” Calcif. Tissue Int., 60: 419-423, (1997).

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