Target-cycling synchronized rolling circle amplification strategy for biosensing of Helicobacter pylori DNA.

Helicobacter pylori have been found to be closely linked with many gastric diseases such as gastric ulcers and duodenal ulcers. Thus, biosensing of H. pylori has attracted wide attention from both scientists and clinicians. Herein, we proposed an electrochemiluminescence (ECL) based platform that can sensitively detect H. pylori DNA. In this platform, a novel target-cycling synchronized rolling circle amplification (RCA) was used for signal amplification. Silver nanoclusters (AgNCs) were synthesized on the circle DNA products, embedding them with the ability to catalyze the electrochemical reduction of K 2 S 2 O 8 , in turn resulting in rapid consumption of ECL co-reactant near the working electrode, leading to the decrease of the ECL emission intensity. In addition to its excellent stability and selectivity, the proposed strategy had a low detection limit of 10 pM, an indication that it can be beneficial for the testing of biosamples. Furthermore, a biosensing chip is designed to improve the throughput, and shed new light on the large scale clinical biosensing applications.