Automated ECL Aptasensing Platform from an Intrarticular Radical Annihilation Route for Distinguishing Glioma Stages

Nowadays, continuous efforts have been devoted to designing stable and high-efficiency electrochemiluminescence (ECL) emitters as alternatives for tris(2,2'-bipyridine)-ruthenium(II) (Ru(bpy)₃²⁺) in medical research. Herein, a novel ECL emitter was obtained by coordinating crystalline covalent triazinyl frameworks (cCTFs) with Ru²⁺ (termed Ru-cCTFs), which exhibited strong ECL emission by the ligand to metal charge transfer (LMCT) route. After its integration with 4-mercaptopyridine (SH-Py), the resultant SH-Py-Ru-cCTFs achieved 2.3-fold enhancement in the ECL efficiency by employing Ru(bpy)₃²⁺ as a standard, which involved a dynamic "intrarticular radical annihilation" ECL pathway. On such foundation, an automated ECL (A-ECL) aptasensor was constructed with an "on-off-on" model and magnetic separation upon linkage of the SH-Py-Ru-cCTFs with streptavidin (SA) magnetic beads (MBs). This automatic assay of miRNA-182 showed a wider linear range from 1.0 to 100.0 fM with a correlation coefficient (R²) of 0.994, a lower limit of detection (LOD) down to 0.28 fM, and faster operation within 41 min. Impressively, this bioassay facilely distinguished the stages of glioma disease from clinical blood samples with high accuracy. Hence, this research sheds light on how to develop advanced ECL luminophores and an automatic method, showing substantial insights into pathogenesis research of gliomas.