A highly sensitive and versatile fluorescent biosensor for pathogen nucleic acid detection based on toehold-mediated strand displacement initiated primer exchange reaction

作者：Zhang, Ye; Li, Zihua; Su, Wanting; Zhong, Guangzhi; Zhang, Xiaohe; Wu, Yuan; Situ, Bo; Xiao, Yunju; Yan, Xiaohui^*; Zheng, Lei^*

来源：Analytica Chimica Acta, 2022, 1221: 340125.

DOI：10.1016/j.aca.2022.340125

• Pathogen nucleic acid
• All in one
• Primer exchange reaction
• Toehold-mediated strand displacement
• One-step assay

Existing detection methods for pathogen nucleic acid detection, such as polymerase chain reaction (PCR), are complicated and expensive to perform. Here, we report a simple and versatile strategy for highly sensitive detection of pathogen nucleic acid based on toehold-mediated strand displacement initiated primer exchange amplification (t-PER). In the presence of the target, the blocked hairpin substrate is released by toehold-mediated strand displacement, which triggers the primer exchange reaction amplification. Then, multiple long tandem repeat single-strands generated by PER open the molecular beacon to recover the fluorescence signal. The t PER protocol also successfully directly detected human papilloma virus from clinical cervical swab samples, with consistent results compared to real time-polymerase chain reaction (RT-PCR). Moreover, the versatility and clinical feasibility of this method was further confirmed by measuring Epstein-Barr virus, hepatitis B virus, and Ureaplasma urealyticum from different clinical samples (serum samples and urine samples). This simple platform enabled specific and sensitive detection of pathogen nucleic acid in a format that might hold great potential for point-of-care infection diagnosis.

• 单位
  广东医学院; 南方医科大学; 广东省人民医院