Determination of cyanide using a chemiluminescence system composed of permanganate, rhodamine B, and gold nanoparticles

Nanoparticles Based Sensors for Cyanide Ion Sensing, Basic Principle, Mechanism and Applications

Rapidly detecting potentially toxic ions such as cyanide is paramount to maintaining a sustainable and environmentally friendly ecosystem for living organisms. In recent years, molecular sensors have been developed to detect cyanide ions, which provide a naked-eye or fluorometric response, making them an ideal choice for cyanide sensing. Nanosensors, on the other hand, have become increasingly popular over the last two decades due water solubility, quick reaction times, environmental friendliness, and straightforward synthesis. Researchers have designed many nanosensors and successfully utilized them for the detection of cyanide ions in various environmental samples. The majority of these sensors use gold and silver-based nanosensors because cyanide ions have a high affinity for these metals ions and coordinate through covalent bonds. These metal nanoparticles are typically combined or coated with fluorescent materials, which quench their fluorescence. However, adding cyanide ions etches out the metal nanoparticles, restoring their fluorescence/color. This principle has been followed by most nanosensors used for cyanide ion sensing. In this review, different nanosensors and their sensing mechanisms are discussed in relation to cyanide ions. The primary purpose is to compare the sensing abilities of these sensors, mainly their sensitivity, advantages, application and to find out research gaps for future work. In this review paper, the development made in nanosensors in the last thirteen years (2010-2023) was discussed and the nanosensors for cyanide ions were compared with molecular sensors while the nanosensors with the excellent limit of detection were highlighted.

Core-shell Au@Pt Nanoparticles Catalyzed Luminol Chemiluminescence for Sensitive Detection of Thiocyanate

In this study, core-shell Au@Pt nanoparticles (Au@Pt NPs) with peroxidase catalytic activity were synthesized by the seed-mediated method, and were used to catalyze the reaction of luminol-H₂O₂ to enhance the chemiluminescence (CL) intensity. It was found that thiocyanate (SCN^-) can effectively inhibit the catalytic activity of Au@Pt NPs. Based on this phenomenon, a method to detect SCN^- by using the Au@Pt NPs-catalytic luminol-H₂O₂ CL system was established, which has an ultra-low detection limit and an ultra-wide linear range, as well as the advantages of being simple and having low-cost and convenient operation. The research mechanism indicated that SCN^- could be adsorbed on the surface of Au@Pt NPs and occupies the active sites of Pt nanostructures, which led to a decrease in the amount of Pt⁰ and a loss of the excellent catalytic activity of Au@Pt NPs. After optimizing the experimental conditions, this assay for detecting SCN^- exhibited a good linear range from 5 to 180 nM, and the low detection limit was 2.9 nM. In addition, this approach has been successfully applied to the detection of SCN^- in tap-water samples, which has practical application value and embodies good development prospects.

Colorimetric and visual detection of cyanide ions based on the morphological transformation of gold nanobipyramids into gold nanoparticles

In this study, we developed a facile, rapid, selective and sensitive colorimetric method for the detection of cyanide ions (CN⁻) by using gold nanobipyramids (Au NBPs).

CdSe quantum dots-sensitized chemiluminescence system and quenching effect of gold nanoclusters for cyanide detection

An efficient chemiluminescence resonance energy transfer (CRET) induced chemiluminescence (CL) system was developed for the sensitive determination of cyanide ion (CN^-) in environmental and biological samples. The selected CL reaction was hydrogen peroxide (H₂O₂)-bicarbonate (HCO₃^-) system with an ultra-weak emission at about 470 nm. It was found that glutathione-stabilized CdSe quantum dots (CdSe QDs) superbly increase the obtained CL intensity. The high performance CRET between the CL emitters and CdSe QDs with a broad absorption was mainly responsible for the observed improving effect. The absorption spectrum of QDs completely overlaps with the CL emission wavelength of H₂O₂-HCO₃^- system. Besides, CdSe QDs could also catalyze the CL reaction of H₂O₂-HCO₃^-, efficiently. On the other hand, it was observed that the gold nanoclusters (Au NCs) could prohibit the CRET system and turn off the CL emission. This diminishing effect can be useful for the analytical application. Herein, it was successfully exploited for the selective recognition of CN^-, using its leaching effect on Au NCs. After efficient dissolution of NCs, the CRET to CdSe QDs restored and the CL emission was again turned on. This strategy resulted in a high sensitive and reliable measurement of CN^- in the concentration range of 2-225 nM, with a detection limit of 0.46 nM.

Ultrasensitive chemiluminescence assay for cimetidine detection based on the synergistic improving effect of Au nanoclusters and graphene quantum dots

A novel and sensitive chemiluminescence (CL) procedure based on the synergetic catalytic effects of gold nanoclusters (Au NCs) and graphene quantum dots (GQDs) was developed for the reliable measurement of cimetidine (CM). The initial experiments showed that the KMnO₄ -based oxidation of alkaline rhodamine B (RhoB) generated a very weak CL emission, which was intensively enhanced in the simultaneous presence of Au NCs and GQDs. CL intermediates can be adsorbed and gathered on the surface of Au NCs, becoming more stable. GQDs participate in the energy transferring processes and facilitate them. These improving effects were simultaneously obtained by adding both Au NCs and GQDs into the RhoB-KMnO₄ reaction. Consequently, the increasing effect of the Au NCs/GQDs mixture was more than that of pure Au NCs or GQDs, and a new nano-assisted powerful CL system was achieved. Furthermore, a marked quenching in the emission of the introduced CL system was observed in the presence of CM, so the system was examined to design a sensitive sensor for CM. After optimization of influencing parameters, the linear lessening in CL emission intensity of KMnO₄ -RhoB-Au NCs/GQDs was verified for CM concentrations in the range 0.8-200 ng ml^-1 . The limit of detection (3S_b /m) was 0.3 ng ml^-1 . Despite being a simple CL method, good sensitivity was obtained for CM detection with reliable results for CM determination in human urine samples.

Graphene nanosheets modified with curcumin-decorated manganese dioxide for ultrasensitive potentiometric sensing of mercury(II), fluoride and cyanide

A glassy carbon electrode (GCE) was modified by electropolymerization of curcumin on MnO₂-Gr nanosheets to obtain a detection method for Hg(II) and for the anions fluoride and cyanide. The complexation by curcumin can be monitored by potentiometry. The results revealed a cathodic shift for the simultaneous detection of fluoride and cyanide and an anodic shift for the mercury(II) sensing, with peak potentials of -0.24, 0.12 and 0.82 V, respectively (vs. Ag/AgCl). The modified GCE is fairly selective, reproducible and repeatable. The detection limits are 19.2 nM for Hg(II), 17.2 nM for fluoride, and 28.3 nM for cyanide (LOD, S/N = 3). The method was successfully applied to the analysis of spiked samples of tap water, river water and petrochemical refinery wastewater. Graphical abstract Schematic of an electrochemical curcumin-MnO₂-graphene nanosheet platform for the simultaneous assay of fluoride, cyanide and mercury(II) in the ppb concentration range in various natural and wastewater samples.

Determination of fluvoxamine maleate in human urine and human serum using alkaline KMnO4 -rhodamine B chemiluminescence

The flow-injection chemiluminescence (FI-CL) behavior of a gold nanocluster (Au NC)-enhanced rhodamine B-KMnO₄ system was studied under alkaline conditions for the first time. In the present study, the as-prepared bovine serum albumin-stabilized Au NCs showed excellent stability and reproducibility. The addition of trace levels of fluvoxamine maleate (Flu) led to an obvious decline in CL intensity in the rhodamine B-KMnO₄ -Au NCs system, which could be used for quantitative detection of Flu. Under optimized conditions, the proposed CL system exhibited a favorable analytical performance for Flu determination in the range 2 to 100 μg ml^-1 . The detection limit for Flu measurement was 0.021 μg ml^-1 . Moreover, this newly developed system revealed outstanding selectivity for Flu detection when compared with a multitude of other species, such as the usual ions, uric acid and a section of hydroxy compounds. Additionally, CL spectra, UV-visible spectroscopes and fluorescence spectra were measured in order to determine the possible reaction mechanism. This approach could be used to detect Flu in human urine and human serum samples with the desired recoveries and could have promising application under physiological conditions.

Sensitive chemiluminescence determination method for 2,4,6-trinitrotoluene based on the catalytic activity of amine-capped gold nanoparticles

TNT can efficiently quench the high intensity CL emission of a rhodamine B–KMnO₄–EDA capped AuNP CL system.

Selective chemiluminescence method for the determination of trinitrotoluene based on molecularly imprinted polymer-capped ZnO quantum dots

A novel molecularly imprinted polymer (MIP) based chemiluminescence (CL) assay is described for the determination of TNT in environmental samples.

A novel and sensitive chemosensor based on a KMnO4–rhodamine B–CdS quantum dot chemiluminescence system for meropenem detection

The reaction of a KMnO₄–Rh B–l-cysteine capped CdS QD system is described as a novel chemiluminescence (CL) reaction. Meropenem exhibits a quenching effect on KMnO₄–Rh B–l-cysteine capped CdS QDs.

Label-free and turn-on fluorescent cyanide sensor based on CdTe quantum dots using silver nanoparticles

A turn-on fluorescence sensor is introduced for determination of trace amount of cyanide, based on glutathione-capped Cd–Te quantum dots.

Sensitive and selective determination of fluvoxamine maleate using a sensitive chemiluminescence system based on the alkaline permanganate-Rhodamine B-gold nanoparticles reaction

A high-yield chemiluminescence (CL) system based on the alkaline permanganate-Rhodamine B reaction was developed for the sensitive determination of fluvoxamine maleate (Flu). Rhodamine B is oxidized by alkaline KMnO4 and a weak CL emission is produced. It was demonstrated that gold nanoparticles greatly enhance this CL emission due to their interaction with Rhodamine B molecules. It is also observed that sodium dodecyl sulfate, an anionic surfactant, can strongly increase this enhancement. In addition, it was demonstrated that a notable decrease in the CL intensity is observed in the presence of Flu. This may be related to Flu oxidation with KMnO4 . There is a linear relationship between the decrease in CL intensity and the Flu concentration over a range of 2-300 µg/L. A new simple, rapid and sensitive CL method was developed for the determination of Flu with a detection limit (3s) of 1.35 µg/L. The proposed method was used for the determination of Flu in pharmaceutical and urine samples.