Related Experiment Video
Updated: Jan 18, 2026
Author Spotlight: Functionalizing Metal-Organic Frameworks: Advancements, Challenges, and the Power of Post-Synthetic Ligand Exchange
Published on: June 23, 2023
Mesoporous Zr MOFs regulated by linear ligand replacement strategy to achieve single Ru(bpy)32+ molecule
Xuemei Wang1, Yawen Zhu1, Bing Sun2
1College of Chemistry and Chemical Engineering, College of Materials Science and Engineering, Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, Qingdao Application Technology Innovation Center of Photoelectric Biosensing for Clinical Diagnosis and Treatment, Instrumental Analysis Center of Qingdao University, Qingdao University, Qingdao, 266071, China.
Abstract:
Rational optimization of the pore size and topology of porous nanocarriers is crucial for improving the loading amount of luminophore and enhancing electrochemiluminescence (ECL) performance. In this study, an equimolar linear ligand replacement strategy was employed to synthesize novel mesoporous metal-organic frameworks (MOFs) for encapsulating Ru(bpy)32+ (Ru@Zr MOFs) under room temperature without an acid modulator. Ingenious ligand substitution allows precise control of pore size, enabling encapsulation at the single-molecule level within mesoporous cages. The external small windows, which are slightly smaller than the internal cavity, effectively inhibit the leakage of Ru(bpy)32+. In addition, to further enhance the charge transfer efficiency, the anode co-reactant polyethyleneimine (PEI) was covalently bound to Ru@Zr MOFs, achieving self-enhanced ECL. Based on this innovative structure, we developed a dual-signal ECL sensor for ultrasensitive detection of miRNA-21. TiO2-Au NPs were introduced as a co-reaction accelerator to amplify the cathodic ECL signal. The ratio of the two signals renders the ECL sensor exceptional sensitivity, with a detection limit as low as 1.8 × 10-18 M. This work highlights the significant advantages of equimolar linear ligand replacement strategy in the mesoporous regulation of MOFs, which is conducive to advancing the development of MOFs-based ECL sensors in biomolecule detection and medical diagnostics.
