The assay bases on the bichinchoninic acid method (1). Proteins reduce alkaline Cu(II) to Cu(I). Bichinchoninic acid forms a purple complex with Cu(I) with an absorbance maximum at 562 nm. The absorbance is directly proportional to protein concentration. • Fast and sensitive assay: linear detection range from 25 – 1000 µg protein/ml • Easy to use: contains ready-to-use reagents and protein standard • Compatible with many detergents • Less binding variation between different proteins than Bradford assay The assay bases on the bichinchoninic acid method (1). Proteins reduce alkaline Cu(II) to Cu(I). Bichinchoninic acid forms a purple complex with Cu(I) with an absorbance maximum at 562 nm. The absorbance is directly proportional to protein concentration. • Fast and sensitive assay: linear detection range from 25 – 1000 µg protein/ml • Easy to use: contains ready-to-use reagents and protein standard • Compatible with many detergents • Less binding variation between different proteins than Bradford assay