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Metal organic gels (MOGs) as a new type of porous soft-hybrid supramolecular material have attracted widespread interest in various aspects due to their unique optical properties. In this work, we report a novel electrochemiluminescence (ECL) emission (679 nm) lanthanide MOG, which has been synthesized by a simple and rapid method at room temperature. This MOG (Tb-Ru-MOG) consists of a central metal ion, terbium (III), and two different ligands, tris­(4,4′-dicarboxylicacid-2,2′-bipyridyl) ruthenium (II) dichloride (Ru­(dcbpy)3 2+) and 4′-(4-carboxyphenyl)-2,2′:6′,2″-terpyridine (Hcptpy). Compared with the classic system of tris­(2,2′-bipyridyl) ruthenium (II) dichloride (Ru­(bpy)3 2+)/S2O8 2–, Tb-Ru-MOG/S2O8 2– owns a narrower potential sweep range (0.00 to −0.85 V) and a more stable and stronger ECL signal. Interestingly, the ECL intensity only decreased 2.0 and 0.1% after continuous scanning for 8000 s and storing at room temperature for 3 months. The possible ECL mechanism has been discussed in detail, which is mainly attributed to the internal synergies (antenna effect and energy transfer) and external co-reactant. Inspired by the unique luminescence characteristics of Tb-Ru-MOG, the application in electroanalytical chemistry was identified by the ECL on–off response for epinephrine with a linear range from 1.0 × 10–10 to 1.0 × 10–3 mol·L–1 and a detection limit of 5.2 × 10–11 mol·L–1. The results suggest that the as-proposed Tb-Ru-MOG will provide a robust pathway for new ECL luminophores in analysis.

The nanohybrids which based on β‐cyclodextrin, platinum nanoparticles and graphene (β‐CD‐PtNPs/GNs) were successfully synthesized and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FT‐IR) and electrochemical impedance spectroscopy (EIS). Then they were used to construct a simple and reliable chiral sensing platform to interact with tryptophan (Trp) enantiomers. Differential pulse voltammetry (DPV) was used to investigate the stereo selectivity of β‐CD‐PtNPs/GNs to Trp enantiomers. After interaction, the obvious difference of peak currents of L‐Trp and D‐Trp was obtained, indicating this strategy could be employed to chiral recognition of Trp enantiomers. Under the optimum conditions, the chiral sensor exhibited a good linear response to Trp enantiomers in a linear range of 5.0×10−5 to 5.0×10−3 M with a low limit of detection of 1.7×10−5 M (S/N=3). This approach provided a new available platform to recognize and determine Trp enantiomers.