Detection of Organophosphorus Pesticides Using Silver-Coated Gold Nanoparticles

Abstract

Plasmonic nanoparticles can provide great utility for the construction of advanced optical and electrical sensors. Herein, we present a versatile sensing strategy that can perform triple-mode detection of organophosphorus pesticides (OPPs) based on carbon dots (CDs)-participated silver deposition on gold nanoparticles (AuNPs). Simply, a hybrid system composed of AuNPs, CDs, and silver ions in phosphate-buffered saline (AuNPs/Ag+/CDs) is designed, and alkaline phosphatase (ALP) is used to catalytically produce l-ascorbic acid, which reduces silver ions to metallic silver on the surface of AuNPs. OPPs can simultaneously modulate triple optical signals, including light absorption, fluorescence, and Rayleigh scattering of the AuNPs/Ag+/CDs hybrid, by inhibiting the activity of ALP, and thus colorimetry, fluorescence, and resonance Rayleigh scattering methods for OPPs are established. Meanwhile, the mechanism of spectral change involved in the three optical signals is investigated in detail. In addition, the proposed detection system is used for the determination of OPPs in vegetables with satisfactory results. The nanohybrid-platform-integrated triple-signal readout provides not only approaches for OPPs detection but also insight for the development of optical sensors.

Förster Resonance Energy Transfer between Multicolor Emissive N-Doped Carbon Quantum Dots and Gold Nanorods for the Detection of H2O2, Glucose, Glutathione, and Acetylcholinesterase

“…The Förster (or fluorescence) resonance energy transfer (FRET) phenomenon has been widely studied because of the confluence of nanomaterials and quantum dots with the biomolecules . The FRET mechanism has been widely used for the establishment of the sensing mechanism for the detection of various types of analytes. , The combination of nitrogen-doped CQDs–gold nanoparticles (AuNPs) has been largely explored as FRET pairs for sensing purposes. − AuNPs are distinct from other metallic nanoparticles because of their good chemical stability . Despite this, their single localized surface plasmon resonance (LSPR) response in only the visible region with poor adjustability is one of the demerits.…”

Ratiometric Dual-Mode Optical Sensor Array for the Identification and Differentiation of Pesticides in Vegetables with Mixed Plasmonic and Fluorescent Nanostructures

“…As a result, these residues can enter the human food chain, posing significant health risks. , Organophosphate pesticides (OPs), such as azinphosmethyl (AZ), thiometon (TM), and oxidemeton-methyl (OX), are extensively used in agriculture. These OPs inhibit the enzyme acetylcholinesterase, which hydrolyzes the neurotransmitter acetylcholine (ACh), leading to an accumulation of ACh and subsequent disruption of the human nervous system. − Additionally, neonicotinoid insecticides (NEOs), including acetamiprid (AC), are widely used on crops as systemic pesticides . NEOs bind strongly and almost irreversibly to nicotinic acetylcholine receptors, inhibiting the binding of these receptors to ACh, causing nervous system damage, paralysis, and even death. − NEOs are often used in conjunction with various OPs on vegetables like cucumbers and lettuce. , The maximum residue levels for four pesticides (AC, AZ, OX, and TM) on lettuce and cucumber, as per the 2020 European Union report on pesticide residues in plants, are set at 1.5, 0.01, 0.01, and 0.0 ppm and 0.4, 0.01, 0.01, and 0.0 ppm, respectively.…”

Paper‐Based Lead Sulfide Quantum Dot Heterojunction Photodetectors

“…The paper‐based device based on the above MoS 2 nanotubes has a responsivity of 2.33 mA W −1 . [ 23 ] As the most mature NIR photosensitive nanomaterials, PbS QDs need to face the dilemma of low carrier mobility. The hybrid strategy of mixing PbS QDs with Au nanocrystals has been used to improve electrical properties, but the detectivity of the device is still at a low level (1.1 × 10 10 Jones).…”