Figure 4 : Stability of complexes [Polymer/pDNA=2/1(weight ratio)] to serum or heparin. A) In the presence of serum. 4 lanes for each polymer with FBS concentration of 0, 10, 25, 50% from left to right; The lowest bands are nonspecific binding of EB to serum components. B) Sodium heparin (0, 10, 25, 50 μg/ml) from left to right.