Work

Target-triggered triplex DNA disassembly on a lateral flow strip enables ultrasensitive, visual thrombin detection

Year: 2026

Type: article

Abstract: We report a novel lateral flow chromatography strip (LFCS) that integrates a target-responsive triplex DNA molecular switch with a carbon nanotube (CNT) label for the point-of-care (POC), ultrasensitive detection of thrombin. The biosensor employs a triplex DNA structure, formed between a thrombin-specific aptamer strand (P0) and an auxiliary strand (P1) covalently anchored to carboxylated CNTs. In the absence of thrombin, the intact triplex sterically hinders P1, preventing signal generation. Upon target binding, the triplex disassembles, activating P1 to hybridize with a capture probe on the test line and leading to the accumulation of CNTs as a visually quantifiable black band. This design leverages the high surface area of CNTs and preserves the aptamer's native affinity. The assay achieves a detection limit of 0.15 nM in buffer, representing a 16.7-fold improvement in sensitivity over a conventional aptamer-gold nanoparticle LFCS. It demonstrates high specificity against non-target proteins and reliable performance in a 10% human serum matrix. By combining a specific conformational switch with a robust nanomaterial label, this work provides a versatile and powerful platform for POC protein detection with significant potential in clinical diagnostics.

Source: Sensors and Actuators Reports

DOI: 10.1016/j.snr.2026.100469

Authors: Zhihao Cheng, Manyan Wu, Yan Huang, Xueji Zhang, Guodong Liu

Institutions: Linyi University, University of Science and Technology Beijing, Peking University People's Hospital, Shenzhen University, Shenzhen University Health Science Center

Language: English

Topic: Advanced biosensing and bioanalysis techniques

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,430