Composite materials have been synthesized by alginate or chitosan encapsulation of polyethylenimine (PEI) derivatives (obtained by glutaraldehyde grafting of histidine and carbon disulfide). Discrete or agglomerated PEI-derivative particles are immobilized in the macroporous network of biopolymer matrix (as shown by scanning electron microscopy and SEM-EDX analysis). The effect of pH and initial concentration on Zn (II) and Cu (II) sorption performance were analyzed. The incorporation of PEI-derivatives biopolymer matrix improves sorption performance in complex solutions (doped with CaCl2) compared to pristine biopolymer. Maximum sorption capacities range from 0.64 to 1 mmol L-1 for Zn (II) and from 1.13 to 1.67 mmol L-1 for Cu (II).