A dual-signal sensor for the analysis of parathion-methyl using silver nanoparticles modified with graphitic carbon nitride

Abstract

A highly sensitive and selective method was developed for both UV–vis spectrophotometric and fluorimetric determination of organophosphorus pesticides (OPs). This method used silver nanoparticles (AgNPs) modified with graphitic carbon nitride (g-C 3 N 4 ). The AgNPs reduced the fluorescence intensity of g-C 3 N 4 . Acetylthiocholine (ATCh) could be catalytically hydrolyzed by acetylcholinesterase (AChE) to form thiocholine, which induces aggregation of the AgNPs. This aggregation led to the recovery of the blue fluorescence of g-C 3 N 4 , with excitation/emission peaks at 310/460 nm. This fluorescence intensity could be reduced again in the presence of OPs because of the inhibitory effect of OPs on the activity of AChE. The degree of reduction was found to be proportional to the concentration of OPs, and the limit of fluorometric detection was 0.0324 μg/L (S/N = 3). In addition, the absorption of the g-C 3 N 4 /AgNPs at 390 nm decreased because of the aggregation of the AgNPs, but was recovered in presence of OPs because of the inhibition of enzyme activity by OPs. This method was successfully applied to the analysis of parathion-methyl in real samples.

Recent advances in silver nanoparticle-based electrochemical sensors for determining organic pollutants in water: a review

“…Recently, they attracted great attention as optical probes for several organic pollutants because of their strong absorption band, which is very sensitive to the particle size, shape, and relative permittivity of the local environment, in the visible region of light 53 . AgNP-based optical sensors were reported for the detection of pesticides 20,[54][55][56][57][58][59] , organic dyes 60 , drugs [61][62] , nitro-aromatics 63 , and mycotoxins 64 . Electrochemical sensors, such as AgNP-based electrochemical sensors, are considered promising for detecting organic pollutants with sufficient sensitivity and selectivity compared with the optical sensors 65 .…”

A machine learning colorimetric biosensor based on acetylcholinesterase and silver nanoparticles for the detection of dichlorvos pesticides

“…22 Recently, electrochemical biosensors [23][24][25][26][27][28] and dual signal sensors using fluorometric and colorimetric read-outs have been developed, based on noble metal nanomaterials like gold and silver nanoparticles. [29][30][31][32] Limitations, in this case, include interfering electroactive materials and additional electrode modification required to get reliable outcomes. 33,34 Using nanomaterials as analytical probes nevertheless has many advantages because of their simple preparation and treatment, relatively low cost of required reagents, as well as rapid, selective, and sensitive results.…”

“…22 Recently, electrochemical biosensors 23–28 and dual signal sensors using fluorometric and colorimetric read-outs have been developed, based on noble metal nanomaterials like gold and silver nanoparticles. 29–32 Limitations, in this case, include interfering electroactive materials and additional electrode modification required to get reliable outcomes. 33,34…”

Electrocatalytic Platform Based on Silver-Doped Sugar Apple-like Cupric Oxide Embedded Functionalized Carbon Nanotubes for Nanomolar Detection of Acetaminophen (APAP)

“…Silver with the highest electrical conductivity among metals possess various outstanding properties suitable for electrochemical sensor development, such as a large surface-to-volume ratio, facilitates electron transfer, non-toxicity, and biocompatibility [ 27 ]. Moreover, various research have reported the excellent electrocatalytic activity of silver nanoparticles [ 28 , 29 , 30 ]. Hence, CuO was doped with Ag nanoparticles in this work.…”