Toxic Anions Research Articles

Sensitive Electrochemical Sensing Properties for Cyanide Detection Using Polyaniline/Cu-Vanadate Nanobelt-modified Electrode

Background: Cyanide is a toxic anion and may be discarded into the water environment, which is a serious threat to human beings and the environment. Hence, it is essential to explore a facile, sensitive method for cyanide detection. Polyaniline/Cu vanadate nanobelts serve as electrode materials for sensitive cyanide determination. Methods: Polyaniline/Cu vanadate nanobelts were obtained by a simple route using polyaniline, Cu vanadate nanobelts. The polyaniline/Cu vanadate nanobelts were measured via electron microscopy, diffraction, infrared spectrum, and electrochemical methods. Results: Amorphous polyaniline nanoparticles with a particle size of about 100 nm were attached firmly to the surface of Cu vanadate nanobelts. Electrochemical sensing properties for cyanide detection were analyzed using a cyclic voltammetry technique using the nanobelts-modified electrode. The cyclic voltammograms (CV) peaks centered at +0.64 V and +0.54 V were observed using the polyaniline/Cu vanadate nanobelts in 0.1 M KCl solution with 2 mM cyanide. The proposed composite nanobelt-modified electrode possessed the detection range and detection limit of 0.001-2 mM and 0.22 μM, respectively. Conclusion: Polyaniline greatly enhances the electro-catalytic performance of the Cu vanadate nanobelt-modified electrode for cyanide detection.

Nanosonosensitizer Optimization for Enhanced Sonodynamic Disease Treatment.

Low-intensity ultrasound-mediated sonodynamic therapy (SDT), which, by design, integrates sonosensitizers and molecular oxygen to generate therapeutic substances (e.g., toxic hydroxyl radicals, superoxide anions, or singlet oxygen) at disease sites, has shown enormous potential for the effective treatment of a variety of diseases. Nanoscale sonosensitizers play a crucial role in the SDT process because their structural, compositional, physicochemical, and biological characteristics are key determinants of therapeutic efficacy. In particular, advances in materials science and nanotechnology have invigorated a series of optimization strategies for augmenting the therapeutic efficacy of nanosonosensitizers. This comprehensive review systematically summarizes, discusses, and highlights state-of-the-art studies on the current achievements of nanosonosensitizer optimization in enhanced sonodynamic disease treatment, with an emphasis on the general design principles of nanosonosensitizers and their optimization strategies, mainly including organic and inorganic nanosonosensitizers. Additionally, recent advancements in optimized nanosonosensitizers for therapeutic applications aimed at treating various diseases, such as cancer, bacterial infections, atherosclerosis, and autoimmune diseases, are clarified in detail. Furthermore, the biological effects of the improved nanosonosensitizers for versatile SDT applications are thoroughly discussed. The review concludes by highlighting the current challenges and future opportunities in this rapidly evolving research field to expedite its practical clinical translation and application.

Fast and efficient chromium(VI) extraction by colloidal Mg/Al layered double hydroxide nanoparticles

Due to the constraints associated with diffusion and mixing time, traditional kinetic and thermodynamic approaches were inadequate for probing the true mechanism of interaction between chromate and Layered Double Hydroxide (LDH). To circumvent these limitations, colloidal suspensions of Mg/Al-NO3 LDH, characterized by a positively charged surface (approximately +50 mV) in ultrapure water and a mean average diameter of 140 nm, allowing the formation of stable suspensions for days, were swiftly mixed with Cr(VI) suspensions at both pH = 4 and 9 using a stopped flow technique. This rapid mixing, accomplished in <5 milliseconds, enabled the examination of the initial stages of interaction between the toxic anion and the host compound. Two distinct steps in the adsorption process were identified: a very fast step (completed in <5 ms), representing up to 80% of the measured variation, and a slower step lasting up to 100 s. The fast step assumed to be driven by electrostatic interaction (ζ ∼ +50 mV) with the surface, and sites close to the surface are easily accessible to the chromate anions. The slower step corresponded to a diffusion process close or inside the particles. Chromate extraction efficiency was investigated through ultrafiltration tests, varying the LDH and chromate amounts, indicating that 2 nitrate ions are exchanged for 1 chromate, regardless of the pH considered, and a total exchange can be fulfilled with 0.1 g L−1 of LDH within the explored concentration range.

A coumarin containing hemicyanine-based probe for dual channel detection of cyanide ion

Cyanide(CN−) is known as one of the most toxic inorganic anions and is harmful to the environment and human health. Its wide use and severe toxicity have led to the development of highly selective cyanide detection, and quantification is desirable. A coumarin-containing hemicyanine-based probe has been developed for highly selective colorimetric and fluorometric detection of cyanide in acetonitrile and aqueous medium. The probe was characterized by 1D NMR (1H and 13C) and HRMS Spectroscopy, and the sensing properties have been studied in colorimetric and fluorometric methods. The high selectivity of the probe for CN− was established by UV–vis and fluorescence spectroscopy in the presence of other competing anions. The probe can detect cyanide as low as 0.7 μM within 90 s. A remarkable change in spectroscopic properties has been observed upon adding cyanide ion. The weakly luminescent probe emitted strongly upon the reaction with CN− which is due to the inhibition of internal charge transfer (ICT) from coumarin to indolinium moiety. Furthermore, the colour change from yellow to colourless and the appearance of a blue luminescence, which can be observed by the naked eye, provides a simple real-time method for cyanide detection, also supported by 1H NMR titration and theoretical study. Furthermore, a paper strip kit loaded with probe has been constructed for a real-time application of CN detection without any interference from other competitive analytes.

Folic acid capping Bi3+-doped Ag quantum dots for enzyme-like dual-mode recognition of toxic S2− and visual sensing of NO2−

BackgroundNO2− and S2− are two kinds of common toxic anions widely distributed in environmental water, soil and food products. Human beings have suffered a lot of diseases from intake of excessive NO2− or S2−, i.e., infantile methemoglobin, cancer and even to death. Although tremendous efforts have been afforded to monitor NO2− and S2−, most were high instrument-depended with complex processing procedures. To keep food safety and to protect human health, it will be a huge challenge to develop a convenient and efficient way to monitor S2− and NO2− in practice. ResultsA kind of folic acid capping Bi3+-doped Ag quantum dots (FA@Bi3+-Ag QDs) was developed for the first time by one-pot homogeneous reduced self-assembly. Not only did FA@Bi3+-Ag QDs possess intrinsic fluorescent property, it expressed synergistic peroxidase-like activity to catalyze the redox of 3,3′,5,5′-tetramethylbenzidine (TMB) and H2O2 with Km/vmax of 0.087 mM/6.61 × 10−8 M s−1 and 6.42 mM/6.25 × 10−7 M s−1 respectively. Interestingly, trace S2− could exclusively alter its fluorescent property and peroxidase-like activity, exhibiting significant hypochromic and “turn-on” fluorescent effects. While trace NO2− could make FA@Bi3+-Ag QDs-TMB-H2O2 system hyperchromic. Under the optimized conditions, FA@Bi3+-Ag QDs were applied for dual-mode recognition of S2− and visual sensing of NO2− in real food samples with satisfactory recoveries, i.e., 100.7–107.9 %/95.8–104.7 % and 97.2–104.8 % respectively. The synergistic enzyme-mimic mechanism of FA@Bi3+-Ag QDs and its selective response mechanisms to S2− and NO2− were also proposed. SignificanceThis represents the first nanozyme-based FA@Bi3+-Ag QDs system for dual-mode recognition of S2− and visual sensing of NO2−, well meeting the basic requirement in drinking water set by WHO. It will offer a promising way for multi-mode monitoring of different pollution using the same nanozyme-based sensor.

Photocatalytic Reduction of Perrhenate and Pertechnetate in a Strongly Acidic Aqueous Solution.

Pertechnetate (99TcO4-), a physiologically toxic radioactive anion, is of great concern due to its high mobility in environmental contamination remediation. Although the soluble oxyanion can be photoreduced to sparingly soluble TcO2·nH2O, its effective removal from a strongly acidic aqueous solution remains a challenge. Here, we found that low-crystalline nitrogen-doped titanium oxide (N-TiO2, 0.6 g L-1) could effectively uptake perrhenate (ReO4-, 10 mg L-1, a nonradioactive surrogate for TcO4-) with 50.8% during 360 min under simulated sunlight irradiation at pH 1.0, but P25 and anatase could not. The nitrogen active center formed by trace nitrogen doping in N-TiO2 can promote the separation and transfer of photogenerated carriers. The positive valence band value of N-TiO2 is slightly higher than those of P25 and anatase, which means that the photogenerated holes have a stronger oxidizability. These holes are involved in the formation of strong reducing •CO2- radicals from formic acid oxidation. The active radicals convert ReO4- to Re(VI), which is subsequently disproportionated to Re(IV) and Re(VII). Effective photocatalytic reduction/removal of Re(VII)/Tc(VII) is performed on the material, which may be considered a potential and convenient strategy for technetium decontamination and extraction in a strongly acidic aqueous solution.

A Zn(II) Coordination Polymer for Fluorescent Turn-Off Selective Sensing of Heavy Metal Cation and Toxic Inorganic Anions.

A novel coordination polymer [Zn(atyha)2]n (1) (Hatyha = 2-(2-aminothiazole-4-yl)-2- hydroxyiminoacetic acid) was constructed by hydrothermal reaction of Zn2+ with Hatyha ligand. CP 1 exhibits a 2D (4,4)-connected topological framework with Schläfli symbol of {44·62}, where atyha- anions serve as tridentate ligands, bridging with Zn2+ through carboxylate, thiazole and oxime groups. CP 1 displays a strong ligand-based photoluminescence at 390 nm in the solid state, and remains significantly structurally stable in water. Interestingly, it can be utilized as a fluorescent probe for selective and sensitive sensing of Fe3+, Cr2O72- and MnO4- through the fluorescent turn-off effect with limit of detection (LOD) of 3.66 × 10-6, 2.38 × 10-5 and 2.94 × 10-6 M, respectively. Moreover, the efficient recyclability for detection of Fe3+ and Cr2O72- is better than that for MnO4-. The mechanisms of fluorescent quenching involve reversible overlap of UV-Vis absorption bands of the analytes (Fe3+, Cr2O72- and MnO4-) with fluorescence excitation and emission bands for CP 1, respectively.

Pillar[5]arene and Azine Derivative Assembly Improved Dual‐Channel Detection of CN–

Comprehensive SummaryThe cyanide anion (CN–) is known to be one of the most toxic anions. Therefore, there is an urgent need to develop a reliable, sensitive, selective, rapid and effective method for the detection of CN–. Here, a self‐assembly strategy based on pillar[5]arene P5 and azine derivative AZ was used to construct supramolecular sensors, and it was found that the detection effect of CN– was significantly improved by the assembly strategy. The sensitivity of the assembled sensor P5‐AZ to CN– is more than 10 times higher than that of AZ. The detect mechanism was further investigated by theoretical calculations and 1H NMR. The results showed that AZ detects CN– by a deprotonation process with fluorescence enhancement, while P5‐AZ improves the sensitivity of CN– recognition through hydrogen bonding, anion‐π and anion‐dipole interactions, as well as the strong bonding ability of the assembly. Supramolecular assembly P5‐AZ has the advantages of low toxicity, high sensitivity, and more importantly, it provides a method to detect CN– sensitivity in the aqueous phase and organisms by host‐guest assembly.

FcCe-MOF-NH2-based colorimetric and fluorometric dual-mode detection of sulfide ions

Sulfide ions, commonly present as toxic anions in industrial processes, require the creation of a convenient and reliable detection platform. In this study, we developed a dual-mode colorimetric and fluorometric method to detect sulfide ions using the cerium-ferrocene bimetal-organic framework (MOF), i.e., FcCe-MOF-NH2, which was synthesized by a common solvo-thermal approach. The FcCe-MOF-NH2 promises the peroxidase-like activity and blue emission peaked at 453 nm. In the presence of H2O2, the FcCe-MOF-NH2 catalyzed 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation, yielding the blue oxidized product (oxTMB), while the fluorescence peak at 453 nm was suppressed due to the inner filter effect (IFE). The Km values of FcCe-MOF-NH2 for TMB and H2O2 were 0.099 mM and 0.179 mM, respectively, showing its good affinity with the substrates. Due to a unique redox reaction between H2O2 and S2−, the peroxidase-like activity of FcCe-MOF-NH2 was markedly suppressed, leading to fluorescence restoration. Hence, the colorimetric and fluorometric dual-mode detection of S2− was realized, exhibiting a linear range of 0.5–100 μM and 0.2–60 μM with a detection limit of 0.43 μM and 0.078 μM, respectively. The developed platform was successfully applied to the detection of S2− in actual water samples.

Oxygen-Evolving Radiotherapy-Radiodynamic Therapy Synergized with NO Gas Therapy by Cerium-Based Rare-Earth Metal-Porphyrin Framework.

The efficacy of traditional radiotherapy (RT) has been severely limited by its significant side effects, as well as tumor hypoxia. Here, the nanoscale cerium (Ce)-based metaloxo clusters (Ce(IV)6)-porphyrin (meso-tetra (4-carboxyphenyl) porphyrin, TCPP) framework loaded with L-arginine (LA) (denoted as LA@Ce(IV)6-TCPP) is developed to serve as a multifarious radio enhancer to heighten X-ray absorption and energy transfer accompanied by O2/NO generation for hypoxia-improved RT-radiodynamic therapy (RDT) and gas therapy. Within tumor cells, LA@Ce(IV)6-TCPP will first react with endogenous H2O2 and inducible NO synthase (iNOS) to produce O2 and NO to respectively increase the oxygen supply and reduce oxygen consumption, thus alleviating tumor hypoxia. Then upon X-ray irradiation, LA@Ce(IV)6-TCPP can significantly enhance hydroxyl radical (•OH) generation from Ce(IV)6 metaloxo clusters for RT and synchronously facilitate singlet oxygen (1O2) generation from adjacently-coordinated TCPP for RDT. Moreover, both the •OH and 1O2 can further react with NO to generate more toxic peroxynitrite anions (ONOO-) to inhibit tumor growth for gas therapy. Benefitting from the alleviation of tumor hypoxia and intensified RT-RDT synergized with gas therapy, LA@Ce(IV)6-TCPP elicited superior anticancer outcomes. This work provides an effective RT strategy by using low doses of X-rays to intensify tumor suppression yet reduce systemic toxicity.

INTERACTION OF (4E)-3-ALKYL(BENZYL)AMINO-4-(HYDROXYIMINO)NAPHTHALENE-1(4H)-ONES WITH 2,2-DIHYDROXY-1,3-INDANEDIONE

Many natural and synthetic quinone, including naphthoquinone derivatives, have some valuable properties. They are known as dyes, antibiotics, vitamins, and antioxidants. Some naphthoquinone derivatives act as cytostatic and antitumor reagents. However, the reduction of the quinoid fragment to the semiquinone radical and, as a consequence, the formation of toxic anion radicals, makes these substances cardiotoxic. The replacement of one or both carbonyl groups with the imino fragment can be one of the ways to solve this problem because iminoquinones have a weak redox cycle. This paper presents the results of the MTT test (primary screening for antitumor activity) of some 3-arylamino-1,4-naphthoquinone-4-oximes which were synthesized earlier. It has been shown that (4E)-4-(hydroxyimino)-3-(p-ethoxyphenylamino)naphtho-1(4H)-one and (4E)-4-(hydroxyimino)-3-(p-tolylamino)naphtho-1(4H)-one are most active against the colon adenocarcinoma and chronic myeloid leukemia in the tumor cell lines, respectively. We have performed the oximation reaction of 2-alkyl(benzyl)amino-1,4-naphthoquinones with hydroxylamine in ethanol to obtain a series of (4E)-3-alkyl(benzyl)amino-4-(hydroxyimino)naphthalene-1(4H)-ones. The reactions of synthesized products with 2,2-dihydroxy-1,3-indanedione (ninhydrin) have been studied under various conditions, i.e., in acetic acid under moderate heating and in dimethyl sulfoxide in the presence of methanesulfonic acid at different temperatures. It has been demonstrated that the interaction of (4E)-3-alkyl(benzyl)amino-4-(hydroxyimino)naphthalene-1(4H)-ones with ninhydrin in acetic acid leads to (6E)-5-alkyl(benzyl)amino-6-гhudroxyimino-4b,11b-dihydroxy-4b,5-dihydrobenzo[f]indeno[1,2-b]indol-11,12(6H,11bH)-diones. More severe conditions (dimethyl sulfoxide, methanesulfonic acid, and heating) leads to a mixture of products, the main of which are 1–alkyl-3'H-spiro[benzo[f]indole-2,1’-isobenzofuran]-3,3’,4,9(1H)-tetraones and 13-alkyl(benzyl)benzo[f]isochromeno[4,3-b]indole-5,7,12(13H)-triones. The yields of the products depend on the chosen temperature regime of the reaction. The structure of all synthesized compounds is confirmed by the physico-chemical methods, i.e., 1H and 13C NMR spectroscopy, IR spectroscopy, high-resolution mass spectrometry, spectrophotometry and elemental analysis. For citation: Gornostaev L.M., Rudenko D.S., Kirik S.D., Krasnov V.I. Interaction of (4E)-3-alkyl(benzyl)amino-4-(hydroxyimino)naphthalene-1(4H)-ones with 2,2-dihydroxy-1,3-indanedione. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 5. P. 24-35. DOI: 10.6060/ivkkt.20246705.7015.

One-pot fabrication of nanoscale zero-valent iron scaffolded onto graphitic carbon nitride as bifunctional nanohybrid in sequestering U(VI) and Cr(VI) with boost performance and intrinsic mechanism

In this paper, we reported an innovative one-pot fabrication approach of a bifunctional nanohybrid through scaffolding of nanoscale zero-valent iron onto the inter-layer structure of graphitic carbon nitride in sequestering U(VI) and Cr(VI) in wastewater. The microstructures, morphologies and chemical compositions of the as–fabricated g-C3N4/NZVI nanohybrid before and after U(VI)/Cr(VI) sequestration were exploited in detail by applying various physicochemical and spectroscopic methods. Batch experimental results demonstrated that sequestration of targeted U(VI)/Cr(VI) by g-C3N4/NZVI was higher than those of pure NZVI or g-C3N4 due to the pronounced boost performance, which was ascribed from the introduction of g-C3N4 as matrix inhibited the oxidation of NZVI and improved its reactivity. The pH effect was also elucidated and it was found that lower pH facilitated the sequestration of the negatively–charged Cr(VI), while higher pH benefited the sequestration of the positively–charged U(VI). Moreover, the characterization insights into intrinsic mechanism manifested that sequestration of U(VI)/Cr(VI) was fulfilled through a synergistic effect of adsorption, reduction and coprecipitation. This work is of great significance for understanding the combined sequestration mechanism of U(VI) and Cr(VI), and usage of g-C3N4/NZVI in sequestration of severe dangerous metal ions, especially efficient detoxification of toxic cations and anions in wastewater.

Fluorescence-based ratiometric sensors as emerging tools for CN− detection: Chemical structures, sensing mechanisms and applications

Hazardous cyanide anions (CN−) are increasingly threatening the environment and human health due to their widespread use in industry and many other fields. Over the past three decades, a large number of probes have been reported to sensitively and selectively detect this toxic anion, while a rather limited number of ratiometric fluorescent probes have been developed. The ratiometric probes have significant potential in bio-imaging and biomedical applications because of the ability to detect CN− in a quick, convenient and affordable way. In this review, we introduce 42 ratiometric fluorescent probes reported in the past 6 years (2018–2023) for CN– detection. Our description includes the chemical structures, photo-physical properties, CN− sensing mechanisms, solution color changes, limits of detection (LODs) and/or various applications of these chemical probes. This review provides guidelines for design and development of a new ratiometric probe for effective CN− detection.

Luminescent MOFs Based on Thiazolo[5,4-d]thiazole as a Chemosensor for the Detection of Environmental Contaminants

Luminescent metal-organic frameworks (LMOFs) are considered special candidates for the sensation and detection of particular analytes. Thiazolo[5,4-d]thiazoles (TTZs) are an ideal type of heterocycles for fluorophores with π-bridge moieties demonstrating structure-function characteristics. LMOFs with excellent sensing properties can be constructed by incorporating heterocyclic aromatic thiazolo[5,4-d]thiazole into the framework. This study has elaborated on LMOFs containing thiazolo[5,4-d]thiazole unit for the detection of environmental contaminants, such as toxic anions, aromatic compounds, and heavy metal ions.

Selective removal of Cr2O72- in aqueous solution by nonporous pure crystals of cucurbit[6]uril.

Cucurbit[6]uril (Q[6]) could serve as a selective absorbent for the toxic anion Cr2O72-, which was demonstrated by the results of UV-vis, ICP, XPS, SEM, and EDS experiments. Single-crystal X-ray diffraction analysis revealed that capture capacity could be attributed to the outer-surface interactions of cucurbit[n]uril between Cr2O72- and the outer surface of Q[6].

Assessment of soil salinity in an average city (on the example of Gus-Khrustalny in Vladimir region)

The research objective was to assess the salinity of soils of an average city with a developed industrial production on the example of Gus-Khrustalny, Vladimir region. It was found that calcium cations and sulfate anions predominate in the studied soils. The increase in the content of individual ions has a local character associated with various sources of pollution. The excess of the maximum permissible concentration of nitrate ions by 1.1 times (145.05 mg/kg) is near the glass factory. The industrial zone of Gus-Khrustalny is characterized by contamination with toxic anions SO4 2–, NO3 –, as well as Mg2+ and K+ cations associated with the specifics of gas-air emissions of enterprises. Roadside areas are mainly contaminated with Na+ and Cl–, which come as part of deicing reagents. The most saline is the sample taken in the transport zone, characterized by a maximum content of Cl– (2819.5 mg/kg), SO4 2– (134.65 mg/kg), Na+ (2046.5 mg/kg) and a value of electrical conductivity (731.8 µS/cm). This study demonstrates that despite the significant impact of industrial enterprises, the primary source of salinization of the city soils is road transport.

A Soluble Porous Coordination Polymer for Fluorescence Sensing of Explosives and Toxic Anions under Homogeneous Environment.

In the past decades, porous coordination polymers (PCPs) based fluorescent (FL) sensors have received intense attention due to their promising applications. In this work, a soluble Zn-PCP is presented as a sensitive probe towards explosive molecules, chromate, and dichromate ions. In former reports, PCP sensors were usually ground into fine powders and then dispersed in solvents to form FL emulsion for sensing applications. However, their insoluble characters would cause the sensing accuracy which is prone to interference from environmental effects. While in this work, the as-made PCP could be directly soluble in organic solvents to form a clear solution with bright blue emission, representing the first soluble PCP based fluorescence sensor to probe explosive molecules under a homogeneous environment. Moreover, the FL PCP solution also shows sensitive detection behaviors towards the toxic anions of CrO42- and Cr2O72-, which exhibit a good linear relationship between the fluorescence intensity of Zn-PCP and the concentrations of both analytes. This work provides a reference for designing task-specific PCP sensors utilized under a homogeneous environment.

A nanocomposite competent to overcome cascade drug resistance in ovarian cancer via mitochondria dysfunction and NO gas synergistic therapy

Ovarian cancer (OC) is one of the most common and recurring malignancies in gynecology. Patients with relapsed OC always develop "cascade drug resistance" (CDR) under repeated chemotherapy, leading to subsequent failure of chemotherapy. To overcome this challenge, amphiphiles (P1) carrying a nitric oxide (NO) donor (Isosorbide 5-mononitrate, ISMN) and high-density disulfide are synthesized for encapsulating mitochondria-targeted tetravalent platinum prodrug (TPt) to construct a nanocomposite (INP@TPt). Mechanism studies indicated that INP@TPt significantly inhibited drug-resistant cells by increasing cellular uptake and mitochondrial accumulation of platinum, depleting glutathione, and preventing apoptosis escape through generating highly toxic peroxynitrite anion (ONOO−). To better replicate the microenvironmental and histological characteristics of the drug resistant primary tumor, an OC patient-derived tumor xenograft (PDXOC) model in BALB/c nude mice was established. INP@TPt showed the best therapeutic effects in the PDXOC model. The corresponding tumor tissues contained high ONOO− levels, which were attributed to the simultaneous release of O2•− and NO in tumor tissues. Taken together, INP@TPt-based systematic strategy showed considerable potential and satisfactory biocompatibility in overcoming platinum CDR, providing practical applications for ovarian therapy.

A potent ratiometric detection and estimation of cyanide in the mainstream smoke of tobacco products by spectroscopic technique

Universal anxiety for the human well-being menaces of cigarette smoking associated with excessive level of toxic metal cations and anions such as cyanide ion are the risky tobacco ingredients which are required to be detected in order to reduce the dose linked with smoke-related diseases. In the current study, a novel and simple naked-eye colorimetric probe PS5 and FPS has been synthesized by nucleophilic addition of 2,4-dinitro phenyl hydrazine with the respective aldehyde P1 and P2 to recognize cyanide ion selectively over other competitive ions. To compare the efficacy of organic and organo-metallic compounds in recognition of cyanide ion, thiazole and ferrocene derived aldehydes have been chosen. Both the probe PS5 and FPS exhibited huge bathochromic shift of ̃100 nm when cyanide ion is introduced to the probe. The emergence of a new peak and diminishing of the existing peak of the probe fulfills the prerequisite for the ratiometric recognition of cyanide ion. Eventually, it also signifies the efficient ICT in the ground state and a vibrant change in color from yellow to pink. The practical applicability of the probe in detection of cyanide ion has been tested in the mainstream smoke of tobacco products. Cyanide levels in smoke from U.S. commercial cigarettes range from 10 to 400 μg/cigarette for mainstream (inhaled) smoke and from 0.006 to 0.27 μg/cigarette for side stream smoke. Thus, our compound can detect 3.807 µg of cyanide present in the smoke which lesser than the actual permitted level of cyanide in the commercial product.

Biosynthesized silver nanoparticles based on bitter orange bloom extract and its application for the determination of cyanide ion in environmental samples

Developing new methods for detecting and determining toxic anions is an essential parameter from waste sources for industrial and environmental scientists. This study presented, a new process for the biosynthesis of silver nanoparticles (AgNPs) based on the bitter orange bloom extract and its potential as a highly selective and sensitive chemosensor for detecting and quantifying cyanide ions. These biosynthesized AgNPs have a sharp and intense surface plasmon resonance (SPR) peak around 405 nm. AgNPs with a yellow color can be changed to colorless in the presence of a certain concentration of cyanide ions due to forming a new adduct between AgNPs and cyanide ions. Hence, the SPR intensity of AgNPs decreases, and the color of the solution becomes colorless. The sensor response to cyanide ions was linear in the concentration range of 49.7 to 1208.8 nM, and the detection limit was equal to 7.9 nM. As an applicable alternative, this assay is highly capable of qualitative and quantitative measurements of cyanide ions in the waste and toxic samples.