Recent progress in inkjet printing of parts of biosensors are highlighted,
with particular reference to the printing of biologically active molecules.
We describe a system constituted by a thermal inkjet printer, adapted to
layering a bidimensional array of dots [701 701 dots per inch] on solid supports. The printer was used to depose a b-galactosidase (GAL)-
containing ink on a polyester sheet, with dots obtained from
10 pL drops, each drop containing in turn 6 pg of enzyme. The activity
of GAL after the preparation was determined using a colorimetric probe
(Brilliant Blue FCF). The activity loss of the microdeposed enzymes was
found to be around 15%, showing that the 2 msec-lasting thermal shock
experienced by the biomolecule into the printhead nozzle affects to a
lesser extent the activity of the thermal inkjet deposited enzyme. In
conclusion, the most recent findings of our group in this line are depicted,
and a view of possible future developments of the “biopolytronics” field
is outlined.
