A Portable Fluorescent Hydrogel-Based Device for On-Site Quantitation of Organophosphorus Pesticides as Low as the Sub-ppb Level

Abstract

Portable devices possess powerful application prospects in on-site sensing without the limitation of bulky instruments. Given the relevance of pesticides to food safety, we herein fabricated a robust gold nanocluster (AuNC)-based hydrogel test kit for precisely quantified chlorpyrifos by using a three-dimensional (3D) printed subsidiary device. In this work, the fluorescence of AuNC-based hydrogel could be efficiently quenched by cobalt oxyhydroxide nanoflakes (CoOOH NFs) through the Förster resonance energy transfer effect. Chlorpyrifos as an acetylcholinesterase inhibitor controls the enzymatic hydrolysis reaction and further regulates the production of thiocholine that could decompose CoOOH nanoflakes into Co2+, resulting in the fluorescence response of AuNC-based hydrogel. By using a homemade subsidiary device and smartphone, the fluorescence color was transformed into digital information, achieving the on-site quantitative detection of chlorpyrifos with the limit of detection of 0.59 ng ml−1. Owing to specific AuNC signatures and hydrogel encapsulation, the proposed fluorescence hydrogel test kit displayed high sensitivity, good selectivity, and anti-interference capability in a real sample analysis, providing great potential in on-site applications.

Synchronous fluorescence detection of nitrite in meat products based on dual-emitting dye@MOF and its portable hydrogel test kit

“…Meanwhile, the kit's response to NO 2 − remained constant in the presence of common interferences, revealing excellent specificity and a strong anti-interference capacity. Apart from the excellent specific identification capability of Rh6G@UIO-66-NH toward NO 2 -, another factor contributing to this specificity might be the ability of the Gel hydrogel to act as a barrier, preventing the infiltration of biomacromolecules and small molecules through its porous structure [49]. In summary, the Gel hydrogel, pretreated with Rh6G@UIO-66-NH 2 , can be used for on-site monitoring and semi-quantitative analysis of NO 2 − with the naked eye.…”

Fluorescent chemosensors facilitate the visualization of plant health and their living environment in sustainable agriculture

“…Hydrogels, serving as water-holding networks, offer nanometer-scale porous structures that enable the passage of small molecules by providing physical encapsulation to trap nanoparticles. 276 The effective integration of the excellent performance of hydrogels with NCs can greatly enhance the accuracy and stability of sensors. For example, Wang et al developed a portable handheld platform integrated with smartphones for the on-site detection of OPs (chemosensor 176 ).…”

“…For example, Wang et al developed a portable handheld platform integrated with smartphones for the on-site detection of OPs (chemosensor 176 ). 276 Cobalt oxyhydroxide nanoflakes (CoOOH NFs) could effectively suppress the fluorescence originating from AuNC hydrogel systems through the FRET effect (Fig. 51b).…”

Preparation of CO2-Responsive Biobased Ternary Composite Microgel and Its Application in Reservoir Gas Channeling Plugging

“…These external stimuli include light, temperature, , pH, , magnetic field, , etc. These materials have high application value and broad application prospects, , such as controllable drug delivery, − intelligent sensors, catalytic control, and so on.…”