posted on 2023-12-23, 14:04authored byChiara Diacci, Bernhard Burtscher, Marcello Berto, Tero-Petri Ruoko, Samuel Lienemann, Pierpaolo Greco, Magnus Berggren, Marco Borsari, Daniel T. Simon, Carlo A. Bortolotti, Fabio Biscarini
We demonstrate an organic electrochemical transistor
(OECT) biosensor
for the detection of interleukin 6 (IL6), an important biomarker associated
with various pathological processes, including chronic inflammation,
inflammaging, cancer, and severe COVID-19 infection. The biosensor
is functionalized with oligonucleotide aptamers engineered to bind
specifically IL6. We developed an easy functionalization strategy
based on gold nanoparticles deposited onto a poly(3,4-ethylenedioxythiophene)
doped with polystyrenesulfonate (PEDOT:PSS) gate electrode for the
subsequent electrodeposition of thiolated aptamers. During this functionalization
step, the reduction of sulfide bonds allows for simultaneous deposition
of a blocking agent. A detection range from picomolar to nanomolar
concentrations for IL6 was achieved, and the selectivity of the device
was assessed against Tumor Necrosis Factor (TNF), another cytokine
involved in the inflammatory processes.