Fig. 1: Assembly and activation of biosensors.
From: Description of an activity-based enzyme biosensor for lung cancer detection
Turbostratic graphene was deagglomerated using sonication (A) and subsequently modified by carboxylation using bromovaleric acid (B). The sensors are further modified by coating with a polymer layer of polyethylenimine (PEI) (C). Enzyme specific peptide sequences terminated with tetrakis-carboxyphenyl-porphorin (TCPP) are added to the surface (D). Incubation with serum containing active protease enzyme results in cleavage of the cognate peptide allowing fluorescence detection in a fluorescent plate reader.
