Rational manipulation of composition and construction toward Zn/Co bimetal hybrids for electromagnetic wave absorption

Rational manipulation of multi-metal hybrids with controllable compositions and constructions is evolv-ing as an efficacious strategy for tunable electromagnetic(EM)characteristics and EM wave(EMW)ab-sorption.Herein,a novel bi-orientation etching approach is proposed to regulate the chemical composi-tions and hybridization construction of Zn/Co hybrids,thence meeting the synergistic interaction among diverse compositions for ultra-high EMW absorption.Attributing to the stepwise heterometallic modi-fication by Zn in Co-ZIFs(Zn@Co-ZIF)and Co in Zn-ZIFs(Co@Zn-ZIF),corresponding pyrolysis products with variable Zn/Co atomic concentration and hybridization states(Zn@Co-C,Co@Zn-C)can be obtained.The Co species was confirmed to have a positive impact on both the dielectric and magnetic response,while an appropriate amount of Zn hybridization in Co substance further enhanced the synergistic ef-fect between multiple loss mechanisms,promoting the minimum reflection loss and effective absorption bandwidth of Zn@Co-C reached-34.99 dB and 5.52 GHz(2.00 mm),respectively.Finally,this work re-veals the composition and construction dependency of bimetal hybrids on EMW absorption,which can be a strong reference for developing EMAs with diverse hybridization structures.

Specific tracking of monoamine oxidase A in heart failure models by a far-red fluorescent probe with an ultra large Stokes shift

Monoamine oxidase A(MAO-A) is a prominent myocardial source of reactive oxygen species(ROS), and its expression and activity are strongly increased in failing hearts. Therefore, accurate evaluation of MAOA activity in cardiomyocytes is of great importance for understanding its biological functions and early diagnosing the progression of heart failure. However, so far, there is no report on the fluorescent diagnosis of heart failure by a specific probe for MAO-A. In this work, two far-red emissive fluorescent turn-on probes(KXS-M1 and KXS-M2) for the highly selective and sensitive detection of MAO-A were fabricated.Both probes exhibit good response to MAO-A, one of which, KXS-M2, performs better than the other one in terms of a fluorescence increment and sensitivity. Using the pioneering probe KXS-M2, specific fluorescence imaging of MAO-A in glucose-deprived H9c2 cardiac cells, zebrafish and isoprenaline-induced failing heart tissues was achieved, proving that KXS-M2 can serve as a powerful tool for the diagnosis and treatment of heart failure.