Nanocomposite of Peroxidase-Like Cucurbit[6]uril with Enzyme-Encapsulated ZIF-8 and Application for Colorimetric Biosensing

Abstract

In this work, cucurbiturils (CBs), a class of macrocyclic supramolecules, were observed to have an interesting peroxidase-like activity, which is metal-free, substrate-specific, thermophilic, acidophilic, and insensitive to ionic strength. By coating CBs on enzyme-encapsulated zeolitic imidazolate framework-8 (ZIF-8), a composite nanozyme was constructed, which retains the catalytic ability of CBs and enzymes and makes them cascade. On addition of the substrate, i.e., the detection target, a highly efficient cascade catalysis can be launched in all the spatial directions to generate sensitive and visible signals. Convenient detection of glucose and cholesterol as models is thereby achieved. More importantly, we have also successfully constructed a composite nanozyme-based sensor array (6 × 8 wells) and thereby achieved simultaneous colorimetric analysis of multiple samples. The concept and successful practice of the construction of the unique core−shell supramolecule/biomolecule@nanomaterial architecture provide the possibility to fabricate next-generation multifunctional materials and create new applications by integrating their unique functions.

3D Printing Technologies in Biosensors Production: Recent Developments

“…A microfluidic paper-based analytical device (µPAD) was printed by photolithography and used for quantitative detection of glucose in human sweat and blood (diabetes diagnosis); the analytical performance reported was comparable with standard commercial glucometers, showing a limit of detection of 25 µM. Another example of 3D printing technologies that was applied to this diagnostic field was provided by Mao et al [43]; they obtained a 3D-printed nanocomposite-based sensor array using cucurbiturils (CB), a macrocycle synthesized from acidic condensation of glycouril and formaldehyde. This supramolecule has an intriguing peroxidase-like catalytic activity, which was exploited for the colorimetric biosensing of glucose and cholesterols in blood samples, with a linear detection range from 2.5 to 250 µM for glucose quantification and 12.5 to 500 µM for cholesterol; limits of detection were 1.2 µM and 2.3 µM, respectively.…”

ZIF-8 induced hydroxyapatite-like crystals enabled superior osteogenic ability of MEW printing PCL scaffolds

“…Zeolitic imidazolate framework-8 (ZIF-8) represents the subfamily of metal-organic framework (MOF) materials, which is comprised by organic ligands of imidazole derivatives and zinc metal ions (Zn 2+ ). [ 1 ] Because of the chemical properties including stable structure, low cytotoxicity, and great specific surface area (SSA), ZIF-8 is used in different biomedical fields, [ 2 – 4 ] such as biological catalysis, [ 5 , 6 ] biosensors, [ 7 ] and drug delivery system (DDS) [ 8 , 9 ]. ZIF-8 has a tetrahedral architecture formed between imidazolate linkers and Zn atoms, and exhibits the hydrolytic stability.…”

Bimetallic FeCo−N−C Catalyst for Efficient Oxygen Reduction Reaction

“…However, metal atoms tend to aggregate into large particles during the pyrolysis process because of the high surface energy, which is not conducive to the effective utilization of metal ions and thus leads to relatively poor ORR activity [10]. Compared with graphene and other substrates, zeolitic imidazolate frameworks (ZIFs) with the porous structure are easier to synthesize due to simple operation, ZIF-based materials have been investigated in many fields because of high thermal stability and tunable surface nature [11,12]. Now, the potential applications of ZIF-derived catalysts in fields of energy conversion have attracted extensive research interest, which promotes the exploration of effective methods to prepare "ideal" electrocatalysts with rich Ndoped carbon species, ordered structure with porous, exceptional chemical stability, and high surface area [13].…”