Purity ~98% (SDS-PAGE). Source: Recombinant corresponding to 70aa from human NAP-2 expressed in E. coli. Molecular Weight: ~8kD Biological Activity: Determined by measuring the dose dependent stimulation of chemotaxis of human neutrophils in a modified Boydon Chamber. Significant chemotaxis is observed with 50ng/ml. The suggested concentration range for in vitro studies is 50ng/ml. The optimal concentration should be determined for each specific application.