The sensing technologies for monitoring
molecular analytes in biological
fluids with high frequency and in real time could enable a broad range
of applications in personalized healthcare and clinical diagnosis.
However, due to the limited dynamic range (less than 81-fold), real-time
analysis of biomolecular concentration varying over multiple orders
of magnitude is a severe challenge faced by this class of analytical
platforms. For the first time, we describe here that temperature-modulated
electrochemical aptamer-based sensors with a dynamically adjustable
calibration-free detection window could enable continuous, real-time,
and accurate response for the several-hundredfold target concentration
changes in unprocessed actual samples. Specifically, we could regulate
the electrode surface temperature of sensors to obtain the corresponding
dynamic range because of the temperature-dependent affinity variations.
This temperature modulation method relies on an alternate hot and
cold electrode reported by our group, whose surface could actively
be heated and cooled without the need for altering ambient temperature,
thus likewise applying for the flowing system. We then performed dual-frequency
calibration-free measurements at different interface temperatures,
thus achieving an extended detection window from 25 to 2500 μM
for procaine in undiluted urine, 1–500 μM for adenosine
triphosphate, and 5–2000 μM for adenosine in undiluted
serum. The resulting sensor architecture could drastically expand
the real-time response range accessible to these continuous, reagent-less
biosensors.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.