Aptamer-Based Gold Nanoparticle Lateral Flow Assay for Rapid Detection of Cardiac Troponin I

Cardiac troponin I (cTnI) is a critical biomarker for the diagnosis of acute myocardial infarction (AMI), but conventional detection methods are often time-consuming and require specialized laboratory equipment. To meet the need for rapid and feasible detection, there is an urgent demand for methods that are fast, specific, and easy to use. In this study, two aptamers (Tro4 and Tro6), which specifically bind to different epitopes of cTnI, were employed to construct a dual-aptamer sandwich system on a lateral flow assay (LFA) strip. The test strip can deliver results within 10 min and shows a detection limit of 11.70 ng·mL^-1. It also exhibited excellent stability after storage at room temperature for up to four months. The assay demonstrated high analytical accuracy, as evidenced by recovery rates from spiked serum samples ranging from 95.11% to 103.17%. These results suggest that the proposed aptamer-based LFA is highly suitable for rapid screening of cTnI, especially in point-of-care settings and resource-limited environments. From a diagnostic perspective, this method holds great promise for improving the timely detection and management of AMI and other myocardial injuries.