Remarkably Enhanced Luminol/H2O2 Chemiluminescence with Excellent Peroxidase-like Activity of FeCoNi-based Metal-Organic Xerogels for the Sensitive Detection of Dopamine

Metal-organicgels (MOGs) are a category of metal-organic smartsoft materials with large specific surface areas, loose porous structures,and open metal active sites. In this work, trimetallic Fe(III)Co(II)Ni(II)-basedMOGs (FeCoNi-MOGs) were synthesized at room temperature via a simpleand mild one-step procedure. Fe3+, Co2+, andNi(2+) were the three central metal ions in it, while 1,3,5-benzenetricarboxylicacid (H3BTC) served as the ligand. The solvent enclosedin it was then removed by freeze-drying to get the corresponding metal-organicxerogels (MOXs). The as-prepared FeCoNi-MOXs have excellent peroxidase-likeactivity and can significantly enhance luminol/H2O2 chemiluminescence (CL) by more than 3000 times, which isvery effective compared with other reported MOXs. Based on the inhibitoryeffect of dopamine on the CL of the FeCoNi-MOXs/luminol/H2O2 system, a simple, rapid, sensitive, and selective CLmethod for dopamine detection was established with a linear rangeof 5-1000 nM and a limit of detection of 2.9 nM (LOD, S/N =3). Furthermore, it has been effectively used for the quantitativemeasurement of dopamine in dopamine injections and human serum samples,with a recovery rate of 99.5-109.1%. This research brings upprospects for the application of MOXs with peroxidase-like activityin CL.