1 research outputs found
Femtomolar Level-Specific Detection of Lead Ions in Aqueous Environments, Using Aptamer-Derivatized Graphene Field-Effect Transistors
The detection of lead ion (Pb2+) contamination
in aqueous
media is relevant for preventing endemic health issues as well as
damage to cognitive and physical health. Existing home kit tests are
unable to achieve clinically relevant sensitivity and specificity.
Here, a label-free graphene field-effect transistor sensor for detecting
Pb2+ at the femtomolar (fM) level, discriminating between
confounding ions, is reported. The sensing principle is based on electrically
monitoring Pb2+-binding-mediated conformational changes
of a specific aptamer tethered to graphene, modeled through the Hills–Langmuir
mechanism. A record sensitivitythrough a
limit of detection of ∼61 fM, for Pb2+ was demonstrated.
For model verification, specific discrimination of
Pb2+ from other ions at the 1 picomolar (pM) level was
shown. The reported work provides motivation for development of portable,
label-free, point-of-care devices with both high
specificity and sensitivity