Electrolyte-gated organic transistors based on donor-acceptor polymers for DNA biosensing

Electrolyte-gated organic transistors (EGOTs) are emerging as promising devices for biosensing applications due to their high transconductance, ability to operate in liquid environments at low voltages and label-free detection capabilities. In this study, we investigate the performance of EGOTs based on the donor-acceptor polymer DPP-DTT, a material known for its high charge mobility and aqueous stability. The device was tested as a biosensor for the detection of mitochondrial DNA (mtDNA), a biomarker associated with multiple sclerosis, as a model analyte. The gate electrode was functionalized with a complementary DNA probe via surface chemistry, with functionalization efficiency validated by surface plasmon resonance and plasmon-enhanced fluorescence spectroscopy. The resulting DPP-DTT-based EGOT sensor exhibited specific detection of mtDNA in solution, with a detection range from 70 pM to 5 nM. These results highlight the potential of DPP-DTT based EGOTs as stable, sensitive platforms for biosensing applications.