Nanoporous ZIF-8 Microparticles as Acetylcholinesterase and Alkaline Phosphatase Mimics for the Selective and Sensitive Detection of Ascorbic Acid Oxidase and Copper Ions

Abstract

In this study, the alkaline phosphatase (ALP)-like activity of zeolitic-imidazolate framework-8 (ZIF-8) is reported for the first time. Then, colorimetric sensors for the ascorbic acid oxidase (AAO) and copper ion (Cu2+) detection were developed based on the acetylcholinesterase (AChE)- and ALP-like activities of ZIF-8. The ZIF-8 has good mimetic enzyme activity and exhibits high affinity to the substrates. Its AChE- and ALP-like activities also have good reusability and storage stability. Good linear dependences are obtained in the range of 1.3−250.0 μM (AChE-like activity-based) and 4.5−454.5 μM (ALP-like activity based) for Cu2+ detection. Furthermore, good linear dependence is also obtained based on the ALP-like activity of ZIF-8 for AAO detection in the range of 2.3−454.5 U/L. Their limits of detection (LODs) are calculated to be 0.7 µM, 2.8 µM, and 1.8 U/L, respectively. Finally, the sample spiked recoveries of Cu2+ in tap water, Cu2+, and AAO in human serum and rabbit plasma were measured, and the results are in the range of 80.0−119.3%. In short, the preparation of ZIF-8 is simple, environmentally friendly, and harmless, and can realize highly selective detection of AAO and Cu2+ in an efficient and fast process.

Rapid and sensitive detection of alkaline phosphatase and glucose oxidase activity through fluorescence and colorimetric dual-mode analysis based on CuO NPs@ZIF-8 mediated enzyme-cascade reactions

“…The K m and V max values of CuO NPs@ZIF-8 with AAP are calculated to be 2.36 mM and 0.92 × 10 −6 M s −1 , respectively, which is similar to that of ZIF-8 ( K m of 11.16 mM). 19 In addition, the K m and V max values of CuO NPs@ZIF-8 with OPD are 1.63 mM and 4.17 × 10 −7 M s −1 , respectively. At present, TMB is one of the most widely used substrates in the study of oxidase-mimicking nanozymes.…”

“…CuO NPs@ZIF-8 has the enzyme-like activity of ZIF-8 and CuO NPs, which can hydrolyze AAP to produce sodium ascorbate and Na 3 PO 4 . 14,19 In addition, the sodium ascorbate can be further hydrolyzed to form a ring-opening substance. At the same time, CuO NPs@ZIF-8 with oxidase activity can oxidize OPD and AA to produce oxidized OPD (CuO NPs@ZIF-8 + OPD/ CuO NPs + AAP + OPD, Fig.…”

Selective fluorescence detection of acetylsalicylic acid, succinic acid and ascorbic acid based on a responsive lanthanide metal fluorescent coordination polymer

“…13 The synthesis of ZIF-8 can be conducted in aqueous solution with a simple and fast process, which possesses good chemical stability, a high surface area and porosity, a uniform porous structure, and various enzyme-like activities. 14 For example, in our previous report, 15 a colorimetric method was developed for the detection of copper ions and ascorbic acid oxidase based on the acetylcholinesterase- and alkaline phosphatase-like activities of ZIF-8. Like the natural esterase (Est), the hydrolase-like activity of ZIF-8 can hydrolyze acetylsalicylic acid (ASA) to salicylic acid (Sal), which is a water-soluble fluorescent organic ligand and has a certain fluorescence intensity through the formation of hydrogen bonds between –COOH and adjacent –OH connected to the benzene ring.…”

Sustainable Zeolite–Silver Nanocomposites via Green Methods for Water Contaminant Mitigation and Modeling Approaches

“…In this context, the development of sustainable and eco-friendly methods for contaminant removal assumes paramount importance. Also in this context, it is crucial to highlight that the primary origins of heavy metals in the surroundings encompass electroplating, battery manufacturing, mining, pulp production, paint manufacturing, metal melting, pigment creation, ceramics, and related sectors [3][4][5]. Metals such as mercury (Hg), lead (Pb), nickel (Ni), zinc (Zn), cadmium (Cd), chromium (Cr), and Copper (Cu) are prevalent heavy metals, classified as perilous waste and acknowledged for their teratogenic and carcinogenic properties [6,7].…”