Ratiometric electrochemical-colorimetric dual-mode biosensor based on Cu-MOF and AuPt@PBA nanomaterials for ultrasensitive and accurate detection of DR1.

Abstract

Hashimoto's thyroiditis (HT) is a prevalent autoimmune disorder that increasingly threats human health and quality of life. As down-regulator of transcription 1 (DR1) is a key biomarker for HT, developing efficient DR1 detection methods is crucial for monitoring disease progression. Here, a novel ratiometric electrochemical-colorimetric dual-mode biosensor was constructed using Cu-based metal-organic framework (Cu-MOF) and AuPt-modified prussian blue analog (AuPt@PBA), enabling ultrasensitive and accurate determination of DR1. Cu-MOF was employed as an internal reference signal for electrochemistry, thereby enhancing the signal accuracy. AuPt@PBA can not only provide redox signals in electrochemical analysis, but also generate colorimetric signals in the presence of H2O2 due to its stable peroxidase-like activity, endowing the nanomaterial with excellent dual-mode sensing performance. Under optimized conditions, the biosensor exhibits a wide linear detection range of 1 × 10-1 pg/mL to 1 × 105 pg/mL in the ratiometric electrochemical mode and 1 × 10-1 pg/mL to 1 × 104 pg/mL in the colorimetric mode, with limits of detections (LODs) as low as 13.6 fg/mL and 28.9 fg/mL, respectively. The cross-validation between these two modes further improves the reliability. Moreover, the dual-mode biosensor demonstrates superior stability and strong anti-interference capability. Consequently, the biosensor holds potential for practical applications.