posted on 2023-12-30, 03:03authored byShufeng Liu, Jialiang Wu, Shuang Li, Li Wang
The development of a simple, rapid, easy-to-operate,
and ultrasensitive
DNA walker-based sensing system is challenging but would be very intriguing
for the enormous applications in biological analysis and disease monitoring.
Herein, a new self-propelled and self-enhanced DNA walking strategy
was developed on the basis of a simple DNA polymerase-steered conversion
from a typical alternate DNA assembly process. The sensing platform
was fabricated easily by immobilizing only one hairpin probe (H1)
and the sensing process was based on a simple one-step mixing with
another hairpin-like DNA probe (H2) and DNA polymerase. The DNA polymerization
could achieve target recycling and successive DNA walking steps. Interestingly,
along with each DNA walking step, the new DNA walker sequence could
be autonomously accumulated for a self-enhanced DNA walking effect.
This provided a multilevel signal amplification ability for the ultrasensitive
detection of the target with a low detection limit of 0.18 fM. Moreover,
it could greatly reduce the reaction time with the sensing process
finished within 1 h. The detection selectivity and the applicative
potential in a complicated biological matrix were also demonstrated.
Furthermore, the flexible control of sensing modes (self-enhanced
DNA walking or the alternate DNA assembly) by using DNA polymerase
or not offered a powerful means for sensing performance modulation.
It thus opens a new avenue toward the development of a DNA walker-based
sensing platform with both rapid and ultrasensitive features and might
hold a huge potential for point-of-care diagnostic applications.