Detection Of Cyanide Ions Research Articles

A Novel Fluorescent Probe for the Detection of Cyanide Ions in Solutions and Studies on Its Biophysical Interactions with ctDNA and Proteases.

A new cationic indolium based styryl dye (Ci) as a fluorescent probe was synthesized and its anions selectivity/sensitivity properties/molecular interactions with protease enzymes (pepsin/trypsin) and ctDNA has been studied by spectroscopic and computational methods. The fluorescence measurements at different temperatures indicated that quenching mechanism of enzymes by Ci was static. ΔH and ΔS data pointed out electrostatic/hydrophobic interactions with pepsin, and also hydrogen bonds/van der Waals forces with trypsin of Ci. According to Förster's non-radiative energy transfer, binding distances (r) were calculated as 3.53/3.27nm for pepsin/trypsin. It was also investigated that groove binding is effective in interaction with ctDNA. The results were supported with molecular docking analyzes which have same tendency. Ci has been demonstrated hypsochromic effect with a decrease in polarity of solventsand it showed highly selective colorimetric and fluorometric sensing behavior for cyanide in organic solvent and inaqueous solution. 1H NMR titration was performed to examine the interaction mechanism between Ci and cyanide. The LOD values of cyanide ion were reported as 4.87 × 10-9M and 9.70 × 10-7M in DMSO and DMSO/H2O binary mixture, respectively. In addition, sensitivity of Ci as a chemosensor to cyanide was investigated in bitter almond samples.

Photometric and Colorimetric Cyanide Detection Sensor Using Amine Based Nitrobenzoxadiazole Derivatives

AbstractThe fluorescent probes 7‐nitro‐N‐phenylbenzo[c][1,2,5]oxadiazol‐4‐amine (1), and 4‐((7‐nitrobenzo[c][1,2,5]oxadiazol‐4‐yl)amino)benzonitrile (2) were synthesised for the detection of cyanide ion (CN−). A new correlative approach with nitrobenzoxadiazole (NBD)‐based probes to detecting CN− by the Donor‐Acceptor D‐A (1) and Acceptor‐Donor‐Acceptor (A‐D‐A) (2) with the aid of DFT calculations are reported. Given their design features, these NBD probes 1 and 2 provide useful insights into the dual‐channel (fluorometric and colorimetric) sensor activity with good selectivity for CN− detection, considerable fluorescence amplification in the presence of CN− ion, and the desirable “Off–on” fluorescent responses toward CN− in the semi‐aqueous medium. The photophysical studies confirmed the A‐D‐A type molecule has a detection limit 0.163 μM for CN− sensing, which is lower than the WHO′s cyanide in water permitted limit. The simple synthetic probes 1 and 2 will offer up new possibilities for industrial effluent CN− detection and bio‐imaging of CN− in a variety of cell lines. This will undoubtedly aid in the understanding of the basic mechanism of CN− poisoning in the bloodstream.

A rapid responsive coumarin-naphthalene derivative for the detection of cyanide ions in cell culture

Cyanide ion (CN−) is widely used in many industrial processes; however, it causes several diseases in humans. Therefore, rapid and accurate detection of CN− is very important and urgent. In this study, a CN− sensor (MH-2) which was capable of detecting CN− ions in living cell was developed. MH-2 gives a rapid color change, absorbance and fluorescence response to CN− in the presence of the anions tested in the working system. The binding ratio between the sensor and CN− was demonstrated by some spectrophotometric methods and the sensing mechanism was investigated by NMR titration experiments, suggesting that MH-2 gives response to CN− via the nucleophilic addition reaction. The fluorescence detection limit and the absorbance detection limit were calculated as 0.056 μM and 0.11 μM, respectively. Both of these detection limits are below the tolerable limit recommended by WHO for CN− in the drinking water (1.9 μM). MH-2 was also applied to living cells for bio-imaging and the results showed that the sensor penetrates the cells and can detect cyanide ions in living cells.

Synthesis, Characterization, and Application of Chalcone Derivatives as Chemosensors for Cyanide Anions

Background: The extreme toxicity of cyanide ions to living organisms encourages the researcher to develop new chemosensors for their sensitive and selective detection. Among various classes of chemosensors, chalcones are believed to be a promising candidate for designing new chemosensors for anions due to easy modification in their skeleton and conjugation system. Research Gap and Problem Statement: Despite having various medical applications and properties, the recognition ability of chalcone derivatives is not widely explored. The traditional methods known for the sensing of cyanide ions are ion chromatography or cyanide selective electrodes. However, these methods need skilled operators and are found to be expensive and time-consuming. Also, the available methods for the detection of cyanide ions are not suitable for on-site monitoring and show interference from other competitive anions, such as fluoride, acetate, and hydroxide ions. Hence, this encouraged us to explore the chalcone derivatives as chemical sensors that are capable of detecting the cyanide ions in the presence of competitive anions, such as fluoride, acetate, and hydroxide ions. Objectives: The development of new chalcone analogs (1E,4E)-1,5-bis(4-chlorophenyl)penta-1,4-dien-3-one (3) and (E)-3-phenyl-1-(pyridin-2-yl)prop-2-en-1-one (6), which are particularly important for the future development of chemosensors for the detection of cyanide ions in the presence of various interfering ions, such as fluoride, acetate, and hydroxide ions. Methods: The sensing behavior of chalcone derivatives (1E,4E)-1,5-bis(4-chlorophenyl)penta-1,4-dien-3-one (3) and (E)-3-phenyl-1-(pyridin-2-yl)prop-2-en-1-one (6) have been investigated toward various anions (CN-, F-, Cl-, Br-, NO3 -, SO4 2-, PO4 2-, OH-, OAc-) using UV-vis spectroscopy. Interestingly, among various anions tested, derivatives (1E,4E)-1,5-bis(4-chlorophenyl)penta-1,4-dien-3-one (3) and (E)-3-phenyl-1-(pyridin-2- yl)prop-2-en-1-one (6) function as highly selective chemosensors for the detection of cyanide ions. Results: We have synthesized two chalcone based derivatives (1E,4E)-1,5-bis(4-chlorophenyl)penta-1,4-dien-3- one (3) and (E)-3-phenyl-1-(pyridin-2-yl)prop-2-en-1-one (6) with simple condensation reaction for the detection of cyanide ions. The various results indicated the quick response of (1E,4E)-1,5-bis(4- chlorophenyl)penta-1,4-dien-3-one (3) and (E)-3-phenyl-1-(pyridin-2-yl)prop-2-en-1-one (6) toward cyanide anions. These two chalcone derivatives showed not only spectral change with selectivity but also showed sensitivity for the detection of cyanide anions. The developed chalcone derivatives detect cyanide ions in the presence of various interfering ions, such as fluoride, acetate, and hydroxide ions. The chemosensors (1E,4E)- 1,5-bis(4-chlorophenyl)penta-1,4-dien-3-one (3) and (E)-3-phenyl-1-(pyridin-2-yl)prop-2-en-1-one (6) for the detection of cyanide ions are particularly smart due to their real-time analysis, simplicity, and low cost in comparison to other closely related processes, such as fluorescence. Conclusion: The sensitivity studies show the high reactivity of derivative 1,5-bis(4-chlorophenyl)penta-1,4- dien-3-one (3) as compared to (E)-3-phenyl-1-(pyridin-2-yl)prop-2-en-1-one (6). The detection limit for derivatives (1E,4E)-1,5-bis(4-chlorophenyl)penta-1,4-dien-3-one (3) and (E)-3-phenyl-1-(pyridin-2-yl)prop-2- en-1-one (6) was 1.2 μM and 300 μM, respectively. The results of (1E,4E)-1,5-bis(4-chlorophenyl)penta-1,4- dien-3-one (3) and (E)-3-phenyl-1-(pyridin-2-yl)prop-2-en-1-one (6) for cyanide detection were satisfying, suggesting their potential application for cyanide detection. Future Direction: The goal of further research of this field is to develop water-soluble chalcone-based probes, which show emission in the Near Infra-Red (NIR) region to provide favorable conditions for biological applications.

A targeted mitochondrial probe based on hemicyanine skeleton for the detection of cyanide ion and its application in seeds and test strips

A targeted mitochondrial probe based on hemicyanine skeleton for the detection of cyanide ion and its application in seeds and test strips

Ecological and Economic Efforts in the Development of Molecular Sensors for the Optical Detection of Cyanide Ions

AbstractCyanide anions have wide use in industrial areas despite their high toxicity to the environment as waste; thus, numerous studies on the determination of this anion have been carried out. This review discusses recent progress in the colorimetric and fluorimetric detection of cyanide by nucleophilic addition or acid‐base reactions to different types of receptors by the chemodosimeter approach. Beyond sensor performance, we focus our analysis on the sustainable synthesis features of five representative families of probes based on small molecules. Some environmental and economic factors are considered (reaction mass efficiency, number of chemical changes, solvent greenness average, preliminary raw material cost, and energy implications), giving a complete picture of the current status of research in this detection field.

Pyrene functionalized oxacalix[4]arene architecture as dual readout sensor for expeditious recognition of cyanide anion.

A pyrene functionalized oxacalix[4]arene architecture (DPOC) was utilized as a fluorescence probe for selective recognition of cyanide ions. The receptor DPOC shows excellent selectivity towards cyanide ion with a red shift of 108nm in absorption band along with a significant change in colour from light yellow to pink. The fluorescence titration experiments further confirm the lower limit of detection as 1.7µM with no significant influences of competing anions. 1H-NMR titration experiments support the deprotonation phenomena, as the -NH proton disappears upon successive addition of cyanide ions. The DFT calculation also indicates a certain increment of -NH bond length upon interaction with cyanide ions. The spectral properties as well as colour of DPOC-CN- system may be reversed upon the addition of Ag+/ Cu2+ ions up to 5 consecutive cycles. Moreover, DPOC coated "test strips" were prepared for visual detection of cyanide ions.

Synthesis and Optimization of Diphenyl Ether‐Based Receptors for the Selective Detection of Cyanide Ions in Neutral Semi‐Aqueous Medium

AbstractThe discharge of toxic cyanide ions in the environment and their uptake by life is inevitable due to industrialization. Therefore, its detection below the permissible limit is significant. Diphenyl ether‐based chromophores have been synthesized and optimized to highlight the proton abstraction mechanism for detecting anions. Absorption studies in the presence of different solvents (H2O, MeOH, ACN, DMSO, CHCl3 and semi‐aqueous ACN) and pH (10 to 4) confirmed the proton abstraction mechanism validated using 1H NMR titration, IR studies and DFT calculations. The effect of substituents on the diphenyl ether motifs highlighted the selectivity of anions under different solvent conditions. Finally, compound‐2 [2‐(2‐methoxyphenoxy)‐5‐nitrobenzoic acid] and compound‐2 c [3‐methoxy‐4‐(2‐nitrophenoxy) benzoic acid] in ACN medium detected F− (280 nM, 17 μM) AcO− (41 nM, 40 μM) and CN− (50 nM. 1.5 μM) ions in nM and μM range respectively. However, the semi‐aqueous medium (5 % water in ACN) gave selective detection of the CN− ion up to 100 nM for the compound‐2 in a 1 : 1 stoichiometry. The use of an aqueous medium in the case of compound‐2 c did not show detection for any of the ions.

An aldehyde-appended salamo-type turn-on optical probe: Rapid detection of trace cyanide ions by structural conversion program

In this work, an aldehyde-appended salamo-type optical probe AA-TNS was synthesized for high-efficiency detection of cyanide ions. Spectral experiments indicated that the probe AA-TNS exhibits a proportional fluorescence response to cyanide ions before/after the detection reaction, accompanied by a remarkable fluorescence turn-on. The probe AA-TNS followed an induced dehydrogenation sensing mechanism, with fast response time and excellent sensitivity. Most importantly, the theoretical calculation revealed that the molecular structure has undergone a transformation from a closed to an extended form, which may be one of the important reasons for the luminescence. This was slightly different from the previously reported probe molecules, which provides some enlightenment for future exploration of salamo-type optical probes. The superior recyclability of the probe molecule was also proved by spectral data and solution fluorescence. Moreover, the probe AA-TNS could directly distinguish cyanide ions in liquid environment and solid-state contact.

A Novel and Reactive Fluorescent “Turn‐on” Probe Based on Benzimidazole Derivative for Selective CN−Detection

AbstractA novel fluorescent probeLbased on benzimidazole derivative for selective CN−detection was designed and synthesized, and its structure was identified by spectral analysis. In DMSO/H2O (v/v=7 : 3, pH=9) solvent system, the fluorescence intensity forLenhances and the color change from yellow to colorless and purple was immediately observed at 426 nm, but there was no obvious color change when other anions instead of CN−was added to the system. The mechanism on CN−recognition was also studied by1H NMR, IR, MS analysis and theoretical calculations. The probeLfor CN−detection exhibited high sensitivity, and the molar ratio and lowest detection limit was 1 : 1 and 8.2×10−7 mol L−1, respectively. In addition, the probeLcould be successfully applied to the detection of CN−in bitter almond, and was also used as a test paper, which indicated that the probeLmight conveniently carried out the quick identification and detection of cyanide ion in the environment and food samples through its fluorescent color change under UV lamp.

Benzothiazole appended 2,2'-(1,4-phenylene)diacetonitrile for the colorimetric and fluorescence detection of cyanide ions.

A benzothiazole appended 2,2'-(1,4-phenylene)diacetonitrile derivative (2Z,2'Z)-2,2'-(1,4-phenylene)bis(3-(3-(benzo[d]thiazol-2-yl)-4-hydroxyphenyl)acrylonitrile) (PDBT) has been synthesized and investigated as a novel sensor, capable of showing high selectivity and sensitivity towards CN- over a wide range of other interfering anions. After reaction with CN-, PDBT shows a new absorption peak at 451 nm with a color transformation from colorless to reddish-brown. When yellow fluorescent PDBT is exposed to CN-, it displays a significant increase in fluorescence at 445 nm, resulting in strong sky-blue fluorescence emission. The nucleophilic addition reaction of CN- plays a role in the sensing mechanism of PDBT to CN-. PDBT can distinguish between a broad variety of interfering anions and CN- with remarkable selectivity and sensitivity. Furthermore, the detection limit of the PDBT probe for CN- is 0.62 μM, which is significantly lower than the WHO standard of 1.9 μM for drinking water. Density functional theory simulations corroborated the observed fluorescence changes and the internal charge transfer process that occurs after cyanide ion addition. In addition, real-time applications of PDBT, such as cell imaging investigations and the detection of CN- in water samples, were successfully carried out.

Optical, Electrochemical, and Test Strip Methods for Sensitive and Selective Detection of Cyanide Ion Using a Multifunctional Π-Extended Azaacene-Based System

Optical, Electrochemical, and Test Strip Methods for Sensitive and Selective Detection of Cyanide Ion Using a Multifunctional Π-Extended Azaacene-Based System

Rapid colorimetric discrimination of cyanide ions - mechanistic insights and applications.

In this work, we have employed an intramolecular charge transfer-based DMN colorimetric probe for the rapid naked-eye detection of cyanide ions in solution as well as real water samples. The intermolecular interaction between the DMN probe and cyanide ions in solution was investigated using a combination of spectroscopic and computational methods in this study. The DMN probe exhibited a selective colorimetric response for cyanide ions over the other anions exposed. The cyanide sensing mechanism of the probe has been investigated by 1H NMR titration and density functional theory calculations. The results reveal that the colorimetric response of the DMN probe is due to the Michael adduct formation in the β-conjugated position of the dicyanovinyl group with cyanide, which blocks intramolecular charge transfer transition. Under optimized experimental conditions, the DMN probe showed a linear plot in the concentration range of 0.01-0.25 μM, with a detection limit of 23 nM. Further, a 3D printed portable accessory for the smartphone and an open-source android application is developed to suit the DMN probe for on-site work. In addition, we have developed the microfluidic paper-based analytical device that could selectively detect cyanide ions at very low concentration using a colorimetric DMN probe. In addition, the DMN probe was effectively used to determine the cyanide ion in a variety of water samples.

Colorimetric detection of cyanide ions using Schiff base derived chemosensor

Cyanide ion sensing is essential owing to its extreme toxicity and poisoning in environment. Schiff base derived chemosensor 3 ((E)-1-(1-(2-hydroxy-5-methylphenyl)ethylidene)-4-(4phenylthaizol-2-yl)semicarbazide), was synthesized by condensation reaction of 4-(4-phenylthiazole-2-yl)semicarbazide with 1-(2-hydroxy-5-methylphenyl)ethenone.for colorimetric detection of cyanide ions. Chemosensor 3 was characterized by NMR studies. The absorbtion studies were carried out in dimethyl formamide (DMF) solution and shows strong absorbtion bands in 280–350 nm region. Addition of cyanide ions into DMF solution of chemosensor 3 results in visually detectable color changes from colorless to yellow due to the formation of hydrogen bonded adduct. A good linearity in the range of 1.66 µM to 11.6 µM with limit of detection value (LOD) 0.5 µM was observed.

Cover Feature: Selective and Sensitive Fluorescence Turn‐On Detection of Cyanide Ions in Water by Post Metallization of a MOF (ChemPlusChem 1/2022)

The Cover Feature shows a potential sensory material (CuCl2@MOF-867), which has been developed by post metallization (CuCl2) of a water stable luminescent metal-organic framework, namely MOF-867, constructed with bipyridyl functionality as organic linker. The sensory probe demonstrates highly selective and sensitive aqueous phase “turn-on” detection towards toxic cyanide (CN-) ions even in the presence of other co-existing anions with a very low limit of detection (0.19 μM), which is considerably lower than the WHO permissible limit in water. More information can be found in the Full Paper by Sujit K. Ghosh, and co-workers.

Selective and Sensitive Fluorescence Turn-On Detection of Cyanide Ions in Water by Post Metallization of a MOF.

Owing to detrimental impact of cyanide ion (CN- ) towards the entire living system as well as its availability in drinking water, it has become very important developing potential sensory materials for the selective and sensitive recognition of CN- ions in water. In the domain of sensory materials, luminescent metal-organic frameworks (LMOFs) have been considered as a promising candidate owing to their unique host-guest interaction, where MOFs can serve as an ideal scaffold for encapsulating relevant guest molecules rendering specific functionality. In this study, a post-synthetically modified MOF (viz., CuCl2 @MOF-867) was applied to recognize cyanide (CN- ) ions in water via "turn-on" response. The bipyridyl functionalities in MOF-867 were used to perform post-synthetic metalation to infiltrate CuCl2 inside porous architecture of the MOF. Moreover, a CuCl2 @MOF-867 based probe demonstrated highly selective and sensitive aqueous phase recognition of CN- ions even in the presence of other interfering anions such as Br- , NO3- , I- , SO42- , OAc- , SCN- , NO2- , etc. The selective binding of CN- ions to the copper-metal center has led to the generation of stable Cu(CN)2 species. This phenomenon has further resulted in a fluorescence turn-on response. The aqueous phase cyanide detection by the rationally modified MOF system exhibited very low limit of detection (0.19 μM), which meets the standardized limit stated by World Health Organization (WHO) that is 1.9 μM.

An indolinium-based chemo-dosimeter for highly selective dual-channel detection of cyanide ion: A combined experimental and theoretical investigations

A new highly selective fluorescent turn-on probe (RS4) possessing indolinium moiety has been designed and synthesized for the detection of cyanide ion. The probe RS4 displays instantaneous, highly selective and sensitive recognition of cyanide ion over other common anions via change in color and enhancement in fluorescence. Nucleophilic addition of cyanide to the indolinium C-atom leads to the enhancement in fluorescence (λem 481 nm; Blueish-green emission) and decolourization due to different intramolecular charge transfer (ICT) process. The binding constant of the 1:2 RS4/CN¯ adduct is determined to be 2.3 × 104 M−1. The limit of detection of cyanide by RS4 is estimated to be 21 nM. Density functional theory (DFT) based calculations strongly substantiate the results of the experimental investigations. Importantly, the probe detects cyanide ion in agro-products (cassava powder and bitter almond), which demonstrates its value to practical application.

Fluorene based fluorescent and colorimetric chemosensors for selective detection of cyanide ions in aqueous medium and application of logic gate

Rising detrimental effects of cyanide due to its frequent large-scale utilization demand rapid and sensitive detection of cyanide ions. Herein, two new fluorene based chemosensors 1 and 2 have been developed through the Suzuki–Miyaura coupling reaction for fluorescence enhancement based selective detection of cyanide with sensitivity levels down to 0.2 ppb and 0.4 ppb, respectively. The plausible sensing mechanism is based on Michael type adduct formation due to the reaction of cyanide with chemosensors and was confirmed by 1H NMR titration, Job’s plot, dynamic light scattering (DLS), and density functional theory (DFT) calculations. Chemosensors 1 and 2 showed excellent linear response towards CN¯ ions (0–100 nM) in the Benesi–Hildebrand plot with association constants (Ka) 1.61 × 106 and 7.1 × 105 M¯1, respectively that corresponds to their favorable chemical reaction. Excellent selectivity of chemosensors for cyanide in the presence of other interferences was investigated through fluorescence emission, UV–Visible, and DFT analysis. Surprisingly, an immediate reversible colorimetric change upon alternate shaking and steadiness of chemosensor − CN¯ solution was noticed indicating that chemosensors can act as promising recyclable sensors for colorimetric on-site detection of CN¯. Meanwhile, chemosensors 1 and 2 displayed highly selective colorimetric detection of CN¯ under daylight and UV radiations (365 nm). Further, cyanide responsive test kits were fabricated that provided a low-cost and portable method for on-site detection of CN¯ ions in an aqueous medium. Finally, chemosensors were successfully applied for designing logic gates, and detection of cyanide in industrial waste and food samples.

A highly selective optical sensor for the detection of cyanide ions in aqueous solution and living cells

A fluorogenic naphthalene based receptor (NFS) has been successfully generated by preparation from 3-amino-2-naphthol and 2-hydroxy-1-naphthaldehyde, it was then characterized. Optical and colorimetric properties of the receptor (NFS) in terms of cyanide (CN-) ions were investigated by several methods including naked-eye detection, UV–vis spectrophotometry and fluorescence spectroscopy. A visual color change from yellow to orangish-pink was observed upon interaction of the receptor with cyanide (CN-) ions in solution, while no color change appeared upon addition of the other anions tested. The detection limit of NFS was calculated as 0.21 µM without any interaction with other anions tested which is lower than that described by the World Health Organization for CN– ions in drinking water. It can be concluded that the receptor (NFS) was sensitive and rapid enough for the detection of CN- ions in solutions. The interaction between the receptor and CN– ions was also investigated by 1H NMR titration, MALDI-Tof mass spectrometry, and FTIR-AR spectroscopy. NFS was also applied to the bio-imaging of human epithelial cell line (HEK 293) and the cell imaging studies demonstrated that the receptor was capable of detecting cyanide ions in living cells.

Novel indoleoxazine derivative cyanide ion probe: Detection applications and cell-imaging studies

A colorimetric fluorescence probe 1-nitro-(8-ethylene-11- (14-diethylaminophenyl)-benzoindo oxazine (ZBO) based on indoleoxazine structure was prepared for detection of cyanide ions (CN−). The introduction of UV difference spectroscopy provides a guarantee for the accuracy of CN− detection. Results indicate that ZBO can achieve the desired recognition of CN− with excellent anti-interference performance. The minimum detection concentration of CN− is 0.1 μM. For practical applications, ZBO test strips were prepared for the convenient and qualitative detection of CN−. The low-concentration solution of ZBO can facilitate the qualitative detection of CN− in peach kernel, loquat seed, and cassava samples. In addition, low cytotoxicity and cell imaging experiments suggested that ZBO can be used for detect CN− in living cells.