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The robust and strong electrochemiluminescence (ECL) emission of organic emitters in an aqueous solution is crucial for expanding their applications in early diagnosis. Herein, a Zn porphyrin-based metal–organic framework ((Zn)porphMOF) was facilely obtained by chelating Zn(II)meso-tetra (4-sulfonatophenyl) porphine (Zn-TSPP) with Zn ions, showing substantially enhanced ECL radiation with K2S2O8 as the coreactant via the "reduction-oxidation" route in aqueous media. In contrast with Zn-TSPP, (Zn)porphMOF displayed 22-fold increase in the ECL intensity because of the agglomeration effect. By virtue of the dramatic confinement towards the energy and electron transfer of ascorbic acid (AA) during the ECL process, an ultrasensitive biosensor was developed with a wide linear range (3.77 to 26.4 μM) and ultra-low detection limit of 0.29 μM at 3 times of the signal-to-noise ratio (3S/N). This work offers a feasible avenue to harvest the steady and boosted ECL responses of organic molecules in aqueous media, also greatly expanding the MOF applications in bioanalysis. [ABSTRACT FROM AUTHOR]

A biomimetic assembly of per-O-methylated-cyclodextrin dimer with cobalt proto-porphyrin (Co III -PPIX@Py2CD) was achieved via covalent linkage between Co III of Co III -PPIX and pyridine N of Py2CD (primarily synthesized by the acyl chlorination reaction of two β-CDs monomers with 3,5-bis (bromomethyl) pyridine). Ultraviolet-visible (UV-vis) and circular dichroism (CD) absorption spectroscopy, and NMR hydrogen spectroscopy (H 1 -NMR) were adopted to carefully characterize the structure of Py2CD and its functional assembly with Co III -PPIX. X-ray photoelectron spectroscopy (XPS) was employed to affirm the binding of the as-obtained Co III -PPIX@Py2CD, whose electrochemical kinetics were extensively studied to validate the feasibility in the catalytic reduction of hydrogen peroxide (H 2 O 2 ). The developed sensor displayed the wide linear range for H 2 O 2 detection and the low detection limit of 2.47 × 10 -7  M. This work sheds some constructive lights on rational design and synthesis of preeminently biomimic carrier and high cost-effectiveness catalyst for (bio)analytical applications., (Copyright © 2019 Elsevier B.V. All rights reserved.)