Surface-initiated DNA self-assembly as an enzyme-free and nanoparticle-free strategy towards signal amplification of an electrochemical DNA sensor

摘要

Surface-initiated DNA polymerization has been employed in thisnwork as an appealing signal amplification strategy for electrochemicalnDNA sensors. This strategy is especially superior in thatnenzymes, colloidal particles and other bulky structures are notninvolved in order to achieve amplified signals, and thus is highlynpromising in circumventing problems due to uncontrolled nucleation,nadsorption, aggregation or disassembly of nanoparticles, liposomesnand proteins, as well as enzyme deactivations. Our preliminarynresults have shown that a decrease (as compared to an amplificationfreensystem) in detection limit by a factor greater than 300 can beneasily achieved by cyclic voltammetry under still not optimizednconditions, with an ability of differentiating a single base mutation.