Intensive and Persistent Chemiluminescence from Orderly Arranged Ligands within Metal–Organic Frameworks for Inflammation Imaging

Chemiluminescence offers ultrasensitive imaging for the diagnosis of a variety of diseases by removing the interference from excitation light sources. Here, we prepared two chemiluminescent metal-organic frameworks (Mn-ADA and Zn-ADA) by using (2<i>E</i>,2'<i>E</i>)-3,3'-(anthracene-9,10-diyl)diacrylic acid (ADA) as a ligand. In Mn-ADA and Zn-ADA, the Mn atoms and Zn atoms are six-coordinated and eight-coordinated, respectively, and their frameworks are different in spatial structure. Due to the orderly arrangement of the fluorescence ligands and one-dimensional channel control of the diffusion of the reactant, Mn-ADA exhibits superstrong intensity and persistent chemiluminescence compared to ADA. The intensity of Mn-ADA is 43 times higher, and the lifetime is two times longer than that of ADA. Furthermore, different coordination also causes the chemiluminescence intensity of Mn-ADA to be stronger than that of Zn-ADA. It is established that Mn-ADA can detect H₂O₂ and image inflammation in mice without the excitation light. This methodology demonstrates the potential of metal-organic frameworks (MOFs) to enhance chemiluminescence and offers a new avenue for the development of MOF materials intended for biomedical application.