Chemical conditions of crosslinking mouse erythrocytes with BS 3 and DTSSP have been studied. These two crosslinking reagents seem to react with band 3 protein in mouse erythrocytes membrane. Extent of crosslinking is dependent on the concentration of the reagent used. Similar cell volumes were observed in crosslinked erythrocytes with respect to control erythrocytes. In vivo behaviour of these modified erythrocytes revealed prominent targeting of crosslinked erythrocytes to liver. This effect is clearly evident when concentrations of 5 mM BS 3 or DTSSP were used and can be dependent of reagent concentration. Consequently, from our results BS 3 and DTSSP can be considered as very useful tools to control and modulate targeting of crosslinked erythrocytes.