Dual-Mode Plasmonic Colorimetric/Photothermal Aptasensor for OTA: Based on a Mn²⁺-Powered DNA Walker for Mediating AuNB Growth.

ABSTRACT: The sensitive and efficient detection of ochratoxin A (OTA) is critical for protecting agricultural ecosystems and public health. A dual-mode plasmonic colorimetric/photothermal aptasensor, based on a Mn²⁺-powered DNA walker for mediating gold nanobipyramid (AuNB) growth, is proposed for OTA detection in this study. In sensing the target OTA, the walking DNA (W-DNA) on the magnetic walker probe was independent and then the environment-friendly Mn²⁺ powered the generation of DNAzyme, where abundant thiol-modified DNA (DNA-SH) was produced by autonomous walking. The positively related DNA-SH level could mediate AuNB growth and reflect dual-mode plasmonic signals. Ultrasensitivity is demonstrated with a limit of detection (LOD) value of 48.6 pg mL^-1 for colori

SUBMITTER: Li Z 

PROVIDER: S-EPMC12607472 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature