Universal Nanoplatform for Formaldehyde Detection Based on the Oxidase-Mimicking Activity of MnO₂ Nanosheets and the In Situ Catalysis-Produced Fluorescence Species

Abstract

Formaldehyde (HCHO) pollution is a scientific problem of general concern and has aroused wide attention. In this work, a fluorometric method for sensitive detection of formaldehyde was developed based on the oxidase-mimicking activity of MnO2 nanosheets in the presence of o-phenylenediamine (OPD). The MnO2 nanosheets were prepared by the bottom-up approach using manganese salt as the precursor, followed by the exfoliation with bovine serum albumin. The as-prepared MnO2 nanosheets displayed excellent oxidase-mimicking activity, and can be used as the nanoplatform for sensing in fluorometric analysis. OPD was used as a typical substrate because MnO2 nanosheets can catalyze the oxidation of OPD to generate yellow 2,3-diaminophenazine (DAP), which can emit bright yellow fluorescence at the wavelength of 560 nm. While in the presence of formaldehyde, the fluorescence was greatly quenched because formaldehyde can react with OPD to form Schiff bases that decreased the oxidation reaction of OPD to DAP. The main mechanism and the selectivity of the platform were studied. As a result, formaldehyde can be sensitively detected in a wide linear range of 0.8–100 μM with the detection limit as low as 6.2 × 10–8 M. The platform can be used for the detection of formaldehyde in air, beer, and various food samples with good performance. This work not only expands the application of MnO2 nanosheets in fluorescence sensing, but also provides a sensitive and selective method for the detection of formaldehyde in various samples via a new mechanism.

A simple phenazine derivative fluorescence sensor for detecting formaldehyde

“…[18][19][20][21] In recent years, researchers have extensively explored works on HCHO detection, overcoming some limitations. [22][23][24][25][26][27] For example, Ji et al designed and successfully prepared a fluorescent nanoprobe P-FA based on the perylene chromophore. This nanoprobe achieved effective detection of both exogenous and endogenous HCHO.…”

ZnO Tips Dotted with Au Nanoparticles—Advanced SERS Determination of Trace Nicotine

“…is used [ 11 ]. E-liquids containing nicotine have been banned in many countries including the Taiwan region [ 12 ]. However, occasionally, nicotine is detectable in e-liquids, leading to inadvertent nicotine inhalation [ 13 , 14 , 15 , 16 ].…”

“Three-in-One” Multifunctional Nanohybrids with Colorimetric Magnetic Catalytic Activities to Enhance Immunochromatographic Diagnosis

“…Owing to their special dual functionalities of colorimetry and catalysis, these nanoparticles have attracted increasing interest in the design and development of highly sensitive colorimetric biosensors. − Since the discovery of iron oxide (Fe 3 O 4 ) nanoparticles with inherent peroxidase-mimicking activity in 2007, attempts have been devoted to exploring nanomaterials with peroxidase-like activity. Currently, available nanomaterials that possess intrinsic peroxidase-like activity predominantly involve iron-based (e.g., Fe 3 O 4 nanoparticles), , noble-metal-based (e.g., cerium oxide and platinum [Pt] nanoparticles), − and carbon-based (e.g., graphene oxide and carbon nanotubes) , nanomaterials. By combining the special physicochemical properties and catalytic activities of these nanoparticles, many high-performance biosensing technologies with a wide range of applications in medical diagnosis, , food safety testing, , and environmental monitoring , have been proposed.…”