These bovine serum albumin (BSA) solutions are protein concentration reference standards for use in BCA, Bradford and other protein assay protocols. BSA is the universally accepted reference protein for total protein quantitation. The albumin standard is precisely formulated at 2 mg/mL in an ultrapure 0.9% sodium chloride (saline) solution. The concentration of the stock solution is calibrated by direct comparison to purified BSA (Fraction V) from the National Institute of Standards and Technology (NIST).