A functionalization technique based on the spontaneous and direct
grafting of aliphatic amines onto hydrogenated diamond was used.
This grafting method was previously proposed [25,26] and can be compared
with a nucleophilic substitution where the ammonium moiety
acts as a leaving group. The grafting solution is made of 10 mM of
butylamine in an aqueous solution containing 0.2 M of phosphate
monobasic adjusted at pH 10. First, 2 ml is filtered in order to wet the
membrane, this latter is then dropped into 5 ml of the grafting solution
for 12 h. Finally, the membrane is thoroughly rinsed with water and
dried.