Work

A glucometer-colorimetric dual mode biosensor for point-of-care testing of cardiac troponin I

Year: 2025

Type: article

Abstract: This study presents a dual-mode glucometer-colorimetric sensor for the detection of cardiac troponin I (cTnI) based on aptamer-specific recognition, localized catalytic hairpin self-assembly, and nicking endonuclease-mediated cyclic amplification. Two partially complementary double-stranded DNAs, DNA1-DNA2, and hairpins H1 and H2 were designed. The introduction of cTnI into the system causes the dissociation of the double strand, generating varying concentrations of DNA2 solution, which triggers localized catalytic self-assembly and the formation of double-stranded H1-H2 with specific nicking sites, undergoing continuous cyclic amplification. The nicking endonuclease recognizes and cleaves these specific sites, producing H2-sucrose invertase and H2-horseradish peroxidase signal probes, enabling dual-mode detection via glucometer and colorimetric methods. The feasibility of this sensor was validated using UV spectrophotometry and polyacrylamide gel electrophoresis. Under optimal conditions, the linear ranges for the glucometer and colorimetric modes were 0.01 ng mL-1 to 20.0 ng mL-1 and 0.03 ng mL-1 to 15.0 ng mL-1, respectively, with detection limits of 0.001 ng mL-1 and 0.005 ng mL-1. The dual-mode sensor exhibits high sensitivity and selectivity, enabling rapid portable dual-mode detection. This method has been successfully applied for the detection of cTnI in human serum, indicating significant potential for clinical applications.

Source: Arabian Journal of Chemistry

DOI: 10.25259/ajc_178_2024