Useful in Sandwich ELISA for Quantitative Detection of Antigen. Aliquot 0.1ml per well of the 50ng/ml, 25ng/ml, 12.5ng/ml, 6.25ng/ml, 3.12ng/ml, 1.56ng/ml, 0.78ng/ml human SPARC standard solutions into the precoated 96-well plate. Add 0.1ml of the sample diluent buffer into the control well (Zero well). Add 0.1ml of each properly diluted sample of human cell culture supernates, serum or human milk to each empty well. We recommend that each human SPARC standard solution and each sample is measured in duplicate.