A portable smartphone-based detection of glyphosate based on inhibiting peroxidase-like activity of heptanoic acid/Prussian blue decorated FeO nanoparticles

• Published in: RSC advances Vol. 12; no. 38; pp. 256 - 2567
• Main Authors: Chen, Dan, Wang, Chunqiong, Yang, Dezhi, Deng, Huimin, Li, Qiulan, Chen, Li, Zhao, Gaokun, Shi, Junli, Zhang, Ke, Yang, Yaling
• Format: Journal Article
• Published: 05-09-2022
• ISSN: 2046-2069
• DOI: 10.1039/d2ra03382h

The rapid and onsite detection of glyphosate in tobacco products is still a great challenge. In this study, a novel smartphone-assisted sensing platform for the detection of glyphosate has been successfully proposed through the peroxidase-like activity of Fe
3
O
4
-based nanozyme. Heptanoic acid/Prussian blue (PB) decorated Fe
3
O
4
nanoparticles (Fe
3
O
4
@C
7
/PB) could catalyze and oxidize 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS, colorless) into a steel blue colored product in the presence of hydrogen peroxide. Glyphosate could specifically inhibit the peroxidase-like activity of Fe
3
O
4
@C
7
/PB by occupying the active site, thereby the glyphosate detection could be accomplished within 10 min by monitoring the color change of ABTS. This study has developed a smartphone-based portable detection platform for online analysis of glyphosate with a detection limit of 0.1 μg mL
−1
. The absorbance response curve of glyphosate showed good linearity in the concentration range of 0.125-15 μg mL
−1
at 415, 647, and 730 nm. Moreover, by employing a co-precipitation technology and inhibiting the peroxidase-like activity, the glyphosate analysis would be less affected by the tobacco sample matrix. The nanosensor possesses excellent selectivity and anti-interference ability, which has application value in actual samples for onsite screening.
The schematic representation of the colorimetric sensors for glyphosate detection.