RB of haemocytes was quantified using the reduction of nitroblue
tetrazolium (NBT) to formazan as a measure of superoxide
anion, as described previously [14]. Briefly, 100 ml diluted haemolymph
(1:9) was placed in triplicate on microplates (96 wells)
previously coated with 100 ml of a poly-L-lysine solution (0.2%)
to improve cell adhesion.