Unveiling MOF-derived CuFe2O4 as a catalytic promoter of Ru(bpy)32⁺ ECL: A CRISPR/Cas13a-based strategy for miR-17 Detection

• A highly sensitive miR-17 ECL biosensor was developed. • MOF-derived porous CuFe 2 O 4 promoted the ECL of the Ru(bpy) 3 2 ⁺/TPrA system. • CRISPR/Cas13a trans-cleavage-triggered HCR amplification strategy were employed. • The platform achieved a remarkable limit of detection (LOD) of 9.23 aM. MicroRNA-17 (miR-17) is a critical biomarker linked to various cancers and diseases, underscoring the need for sensitive and selective detection methods. Herein, an ultra-sensitive electrochemiluminescent (ECL) sensor for miR-17 detection utilizing MOF-derived porous CuFe 2 O 4 nanospheres and CRISPR/Cas13a trans-cleavage-triggered hybridization chain reaction (HCR) amplification was presented. The porous CuFe 2 O 4 nanospheres possessed a high surface area and excellent catalytic activity, significantly enhancing ECL emission. To the best of our knowledge, this is the first report demonstrating that MOF-derived CuFe 2 O 4 can effectively enhance the electrochemiluminescence of Ru(bpy) 3 2 ⁺ for miR-17 detection. The CRISPR/Cas13a system provided miR-17 recognition and trans-cleavage activity, triggering HCR for signal amplification. Under optimized conditions, the biosensor exhibited a wide linear detection range from 20 aM to 5000 aM, with a detection limit of 9.23 aM. The system discriminated miR-17 from closely related miRNAs with negligible cross-reactivity, which demonstrated its outstanding selectivity. Practical applicability was confirmed by successful quantification of miR-17 in diluted human serum which achieved recovery rates between 95.2% and 104.8%. The results validated the biosensor’s potential for early disease diagnosis and clinical monitoring of miR-17-associated disorders.