Electrochemiluminescent Enantioselective Recognition on Chiral Channel-Engineered Metal-Organic Framework...

Chiral discrimination by a simple and efficient sensing means is highly desirable but a challenge for the study of chiral compounds. In this work, a chiral metal-organic framework (CMOF) with a tailored channel size is combined for the first time with electrochemiluminescence (ECL) in a synergistic approach to construct a chiral recognition ECL (CR-ECL) system for efficient discrimination of tryptophan (Trp) enantiomers. Notably, Trp functions dually as both the analyte and the co-reactant, generating distinct ECL signals in the presence of the luminophore (sodium tetraphenylborate, TPB). The chiral-functionalized MOF808-His, with its precisely designed channels and pores, preferentially permits the transport and oxidation of L-Trp, leading to a significantly stronger luminescence signal compared to D-Trp. Owing to the enantioselective recognition enabled by the unique chiral channels, a high recognition efficiency is achieved with an ECL intensity ratio (ECL_L/ECL_D) of 13.4, demonstrating excellent ECL enantioselectivity. This study pioneers a novel strategy for developing CR-ECL systems based on the channel-engineered CMOF. It not only offers a simple, rapid, and cost-effective approach for enantioselective recognition but also innovatively advances the application of channel-engineered CMOF in chiral discrimination and ECL-based bioassays.