Dual-Modal Lateral Flow Test Strip Assisted by Near-Infrared-Powered Nanomotors for Direct Quantitative Detection of...

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Molecular Diagnostics

Background:

• MicroRNA (miRNA) quantification is crucial for early disease diagnosis, but current methods face challenges with inefficient target capture in complex biological samples.
• Passive diffusion of detection probes limits the accuracy and sensitivity of traditional miRNA detection assays.

Purpose of the Study:

• To develop an amplification-free, quantitative method for detecting miRNA-21 using near-infrared (NIR)-powered Janus nanomotors (JNMs) to improve capture efficiency.
• To integrate these JNMs with a lateral flow test strip (LFTS) for point-of-care detection of miRNA-21 in biological samples.

Main Methods:

• NIR-powered Janus nanomotors (AuNR/PMO JNMs) conjugated with DNA probes were designed to capture miRNA-21.
• The JNMs' self-propelled thermophoretic motion under NIR irradiation was utilized to accelerate target recognition and enhance capture efficiency.
• The JNM-assisted LFTS assay was developed for direct quantitative detection using visual and thermal signals.

Main Results:

• The JNM-assisted capture efficiency for miRNA-21 improved from 59.39% to 86.12% in reaction buffer.
• A limit-of-detection of 18 fmol/L for miRNA-21 was achieved, representing a 12.22-fold improvement over static probes.
• The assay demonstrated successful detection of miRNA-21 in spiked serum samples and cell medium.

Conclusions:

• The AuNR/PMO JNM-assisted LFTS system provides a sensitive and efficient platform for direct, amplification-free miRNA detection.
• This technology offers a promising point-of-care testing strategy for precise miRNA quantification in real biological samples.
• The developed system holds significant potential for the early diagnosis and management of miRNA-related diseases.