A simple yet sensitive Pseudomonas aeruginosa detection method based on self-priming mediated conformation of split G‑quadruplex

Abstract Accurate and reliable detection of Pseudomonas aeruginosa ( P. aeruginosa ) is crucial for the early diagnosis of infections. We present a simple technique for the sensitive and reliable detection of P. aeruginosa by combining aptamer-based target recognition with self-priming induced conformation of split G-quadruplex. This approach employs an aptamer sequence for precise target detection to release the “7*” sequences which subsequently initiates DNA polymerase/endonuclease assisted chain extension and displacement-mediated cascade signal amplification. The method offers several advantages: i) it is simple, utilizing a single probe for signal amplification without the need for intricate primer design; ii) the multiple signal amplification processes confer high sensitivity, achieving a low limit of detection (LOD) of 3.5 cfu/mL, which is superior to or comparable with many previous methods; iii) malachite green (MG)-mediated aggregation-induced emission is cost-effective and exhibits excellent photostability. This approach allows the entire detection process to be completed within 90 min and necessitates minimal instrumentation. This detection approach demonstrates significant promise for application in point-of-care testing.