design offered cooperative hybridization between the capture
probes on the solid surface and the multiple CEs binding to
one target, presumably leading to a stronger capture than
single CE–capture probe interaction [5], which makes sure
that only the specific target can be captured to the solid surface
and further trigger downstream cascade reactions.
- As the hybridization is taken place at a temperature (58C)
that is higher than the annealing temperature of single CE or
LE probe, single probes or hairpins will be washed off and
cannot be stably immobilized on the solid surface to cause
nonspecific absorption. Leaky hairpin polymerization products
without binding to the target will be washed off as well without
causing background.
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196 Yao Xu and Zhi Zheng