Ratiometric Assays for Acetylcholinesterase Activity and Organo‐Phosphorous Pesticide Based on Superior Carbon Quantum Dots and BLGF‐Protected Gold Nanoclusters FRET Process

Abstract

A ratiometric fluorescence system is reported based on fluorescence resonance energy transfer (FRET) between carbon quantum dots (CQDs) and gold nanoclusters (Au NCs) for sensitive detection of acetylcholinesterase (AChE) and organophosphorus pesticides (OPPs). The CQDs and Au NCs were synthesized by one-pot approach, emitting at 420 nm (λ ex = 320 nm) and 680 nm (λ ex = 500 nm) respectively. To verify the effect on CQDsÀ Au NCs of biothiols, the thiol sensing was performed by measuring the ratio of F 680 /F 420 as the increasing of cysteine as model, which shows a low detection limit of 1.07 μmol L À 1 . Herein, this sensing system was employed to determine AChE activity depend on its hydrolysis for acetylcho-line (ATCh) generated thiocholine. The AChE activity can be assayed as low as 1.08 mU mL À 1 within a wide linear range from 3 to 50 mU mL À 1 and evaluated in practical samples. In addition, a kind of organophosphorus pesticide, hypertoxic diazinon, was selected to efficiently inhibit the ATCh hydrolysis, and can be detected based on this proposed strategy. As far as we known, the proposed ratiometric assay system based on CQDsÀ Au NCs nanocomposites is the first time to demonstrate for AChE and OPPs assay. We believed that this promising strategy will opens up a novel pathway of using CQDs and Au NCs for the expanded biosensing applications.

Multicolor Carbon Dots Prepared by Single‐Factor Control of Graphitization and Surface Oxidation for High‐Quality White Light‐Emitting Diodes

“…Carbon dots (CDs) have garnered tremendous attention in the field of nanomaterials owing to their adjustable photoluminescence, wide source of raw materials, easy modification, and high stability. It has shown a great potential application value, especially in fields such as biological imaging, [ 1,2 ] drug release, [ 3,4 ] fluorescent probes, [ 5,6 ] optoelectronic devices, [ 7,8 ] and photocatalysis. [ 9,10 ]…”

“…Carbon dots (CDs) have garnered tremendous attention in the field of nanomaterials owing to their adjustable photoluminescence, wide source of raw materials, easy modification, and high stability. It has shown a great potential application value, especially in fields such as biological imaging, [1,2] drug release, [3,4] fluorescent probes, [5,6] optoelectronic devices, [7,8] and photocatalysis. [9,10] Since CDs were discovered in 2004, various synthetic methods have been developed, including arc discharge, [11] laser ablation, [12] chemical oxidation, [13] microwave-assisted, [14,15] hydrothermal, [16][17][18] solvothermal, [19][20] and solution chemistry.…”

Development of a carbon quantum dot-based sensor for the detection of acetylcholinesterase and the organophosphate pesticide

“…The overstimulation of the cholinergic system can cause many symptoms such as paralysis, seizures, and respiratory failure, which may finally lead to death [ 9 ]. Organophosphorus pesticides (OPs) are potent irreversible AChE inhibitors that covalently bind to serine residues at the AChE's active site, thereby inhibiting AChE's activity [ [10] , [11] , [12] ]. OP pesticides are classified as extremely dangerous compounds, with a broad spectrum of toxicity types, by the World Health Organization (WHO).…”

Ratiometric fluorescence assay based on carbon dots and Cu2+-catalyzed oxidation ofO-phenylenediamine for the effective detection of deferasirox

“…[36][37][38] Combined with uorescent probes with different emission wavelengths and connement effect of some agents, several ratiometric uorescent strategies based on the FRET principle are developed. [38][39][40][41][42] O-Phenylenediamine (OPD) can be controllably oxidized to yellow uorescent 2,3-diaminophenazine (oxOPD) by various oxidants, such as Cu 2+ , 43,44 Ag + , 45 MnO 2 (ref. 46) and H 2 O 2 .…”