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A Dual-Sensing DNA Nanostructure with an Ultrabroad Detection Range
journal contribution
posted on 2019-10-10, 02:13 authored by Byunghwa Kang, Soyeon V. Park, Hyongsok Tom Soh, Seung Soo OhDespite
considerable interest in the development of biosensors
that can measure analyte concentrations with a dynamic range spanning
many orders of magnitude, this goal has proven difficult to achieve.
We describe here a modular biosensor architecture that integrates
two different readout mechanisms into a single-molecule construct
that can achieve target detection across an extraordinarily broad
dynamic range. Our dual-mode readout DNA biosensor combines an aptamer
and a DNAzyme to quantify adenosine triphosphate (ATP) with two different
mechanisms, which respond to low (micromolar) and high (millimolar)
concentrations by generating distinct readouts based on changes in
fluorescence and absorbance, respectively. Importantly, we have also
devised regulatory strategies to fine-tune the target detection range
of each sensor module by controlling the target-sensitivity of each
readout mechanism. Using this strategy, we report the detection of
ATP at a dynamic range spanning 1–500 000 μM,
more than 5 orders of magnitude, representing the largest dynamic
range reported to date with a single biosensor construct.