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1.
Food Chem ; 354: 129405, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33770563

RESUMO

The intake of cassava would probably induce adverse health effects since there are toxic cyanide in cassava. However, the risk assessment of cassava consumption has not been reported in China. Therefore, this paper aimed to evaluate the dietary risks of cassava cyanide and proposed a maximum residue limit (MRL) for cyanogenic glycosides (CNGs) in cassava. The retention rate of CNGs and CN- were 61% and 11% after boiling, respectively. The acute dietary exposure of CN- and CNGs were 0.6-fold and 1.7-fold of acute risk reference dose, respectively. There was no chronic health risk across all populations concerning cassava consumption. The MRL of CNGs was proposed as 200 mg/kg in cassava. Risk assessment of cyanide for foods rich in CNGs was suggested to be based on CNGs quantification rather than that of CN-.


Assuntos
Cianetos/análise , Exposição Dietética , Manihot/química , China , Cromatografia Líquida de Alta Pressão , Culinária , Glicosídeos/análise , Humanos , Manihot/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Medição de Risco , Espectrometria de Massas em Tandem
2.
Ecotoxicol Environ Saf ; 211: 111907, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33453637

RESUMO

Oxidation of phenol, cyanide and aniline have been analyzed by the enhanced electro-oxidation process in which sodium chlorite was used as an electrolyte and results were validated using statistical tool based on Box-Behnken design. The mineralization efficiency of 78.4%, and 98.18% were predicted at optimized variables condition for phenol, and aniline respectively, whereas complete mineralization has been observed for the cyanide at the optimized conditions, which describes the significance of the design model approach.The process mineralizes the higher phenol concentration revealing a drastic reduction in power consumption in comparison of direct oxidation, i.e., 799.36 kWh/kg to 138.18 kWh/kg for more than 90% mineralization of phenol even at a higher current density of 13.63 mA/cm2. The kinetic modelling approach justified that higher current density has also played a role in higher mineralization of pollutants at the specific operating conditions. The by-product formation and toxicity effect on microalgae in wastewater were assessed by the full scan mass spectrometry and microalgae pigment inhibition test after the electro-oxidation of coking wastewater. The pigment growth inhibition rate of Chlorella sp. NCQ and Micractinium sp. NCS2 suggests that sodium chlorite as an electrolyte aid can also effectively used as an oxidizing agent and algal inhibiter in the coking wastewater.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/toxicidade , Compostos de Anilina , Chlorella , Compostos Clorados , Coque/análise , Cianetos/análise , Poluentes Ambientais/análise , Peróxido de Hidrogênio/química , Microalgas , Oxirredução , Óxidos , Fenol/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise
3.
Food Chem ; 331: 127359, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32580128

RESUMO

Cyanide is a highly toxic anion. Nonetheless, many food plants could produce endogenous cyanide, which causes great danger to human health. Thus, monitoring cyanide in food samples is critically significant. Herein, we rationally developed the first ratiometric near-infrared fluorescent probe for sensing cyanide in food samples. The probe displayed noticeable fluorescence in near-infrared region. Moreover, upon treatment with cyanide, the probe exhibited highly selective and sensitive ratiometric fluorescence response, with limit of detection determined to be 0.075 µM and limit of quantification determined to be 0.25 µM. The ratios of fluorescent intensities at 519 and 688 nm (I519/I688) was linear with added cyanide concentrations from 0 to 80 µM. The relative standard deviations for repeatability and reproducibility varied from 0.55 to 8.94 and from 1.17 to 9.46, respectively. Significantly, probe Hy has been successfully applied for monitoring cyanide in various food samples, such as almonds, sprouting potatoes, and bamboo shoots.


Assuntos
Cianetos/análise , Corantes Fluorescentes/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Limite de Detecção , Prunus dulcis/química , Reprodutibilidade dos Testes , Sasa/química , Sensibilidade e Especificidade , Solanum tuberosum/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos
4.
Sud Med Ekspert ; 63(2): 41-46, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32297498

RESUMO

In this article, we consider features of the referral of biological material and assessment of medical and legal chemical researches at emergencies of technogenic character, plane crashes, the fires with the numerous human victims. Practical recommendations on obtaining of biological material for a research on volatile organic compounds, including ethyl alcohol and its metabolites, volatile products of burning, including monoxide of carbon and cyanides are made. Features and the recommended order of conducting judicial and chemical examination at emergencies are designated.


Assuntos
Emergências , Manejo de Espécimes , Monóxido de Carbono/análise , Cianetos/análise , Etanol/análise , Incêndios , Humanos , Compostos Orgânicos Voláteis/análise
5.
Neurology ; 94(14): e1495-e1501, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32127386

RESUMO

OBJECTIVE: To identify the etiology of an outbreak of spastic paraparesis among women and children in the Western Province of Zambia suspected to be konzo. METHODS: We conducted an outbreak investigation of individuals from Mongu District, Western Province, Zambia, who previously developed lower extremity weakness. Cases were classified with the World Health Organization definition of konzo. Active case finding was conducted through door-to-door evaluation in affected villages and sensitization at local health clinics. Demographic, medical, and dietary history was used to identify common exposures in all cases. Urine and blood specimens were taken to evaluate for konzo and alternative etiologies. RESULTS: We identified 32 cases of konzo exclusively affecting children 6 to 14 years of age and predominantly females >14 years of age. Fourteen of 15 (93%) cases ≥15 years of age were female, 11 (73%) of whom were breastfeeding at the time of symptom onset. Cassava was the most commonly consumed food (median [range] 14 [4-21] times per week), while protein-rich foods were consumed <1 time per week for all cases. Of the 30 patients providing urine specimens, median thiocyanate level was 281 (interquartile range 149-522) µmol/L, and 73% of urine samples had thiocyanate levels >136 µmol/L, the 95th percentile of the US population in 2013 to 2014. CONCLUSION: This investigation revealed the first documented cases of konzo in Zambia, occurring in poor communities with diets high in cassava and low in protein, consistent with previous descriptions from neighboring countries.


Assuntos
Paraparesia Espástica/epidemiologia , Adolescente , Fatores Etários , Aleitamento Materno , Criança , Cianetos/análise , Dieta , Surtos de Doenças , Feminino , Humanos , Masculino , Manihot/química , Debilidade Muscular/epidemiologia , Debilidade Muscular/etiologia , Deficiência de Proteína/epidemiologia , Chuva , Estações do Ano , Tiocianatos/urina , Adulto Jovem , Zâmbia/epidemiologia
6.
PLoS One ; 15(2): e0228641, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32053630

RESUMO

The use of plant tissue analysis as a tool for attaining low cyanogenic glucoside levels in cassava roots, has hardly been investigated. Just as the quality of crops is improved through the use of plant tissue analysis, the same can probably be done to consistently attain the lowest possible cyanogenic glucoside levels in cassava roots. High levels of cyanogenic glucosides in consumed fresh cassava roots or in their products have the potential of causing cyanide intoxication, hence the need to lower them. An experiment was thus conducted to assess the occurrence of meaningful relationships between plant nutritional status and cyanogenic glucoside production in cassava roots. Total hydrogen cyanide (HCN) levels in cassava roots were used to assess cyanogenic glucoside production. Using NPK fertiliser application to induce changes in plant nutritional status, the main objective of the study was investigated using the following sub-objectives; (1) to determine the effects of increased NPK fertiliser application on cassava root HCN levels; (2) and to show the occurrence of relationships between changes in nutrient levels in plant 'indicator tissue' and HCN levels in cassava roots. The study was a field experiment laid out as a split-plot in a randomized complete block design with three replicates. It was repeated in two consecutive years, with soil nutrient deficiencies only being corrected in the second year. The varieties Salanga, Kalinda, Supa and Kiroba were used in the experiment, while the NPK fertiliser treatments included; a control with no fertiliser applied; a moderate NPK treatment (50 kg N + 10 kg P + 50 kg K /ha); and a high NPK treatment (100 kg N + 25 kg P + 100 kg K /ha). A potassium only treatment (50 kg K/ha) was also included, but mainly for comparison. The root HCN levels of Salanga, Kalinda and Kiroba were significantly influenced by NPK fertiliser application in at least one of the two field experiments, while those of Supa remained uninfluenced. Changes in plant nutritional status in response to fertiliser application were thus shown to influence cyanogenic glucoside production. The results of the multiple linear regression analysis for the first field experiment, generally showed that the root HCN levels of some cassava varieties could have been 'reduced' by decreasing concentrations of nitrogen, potassium and magnesium in plants, or by improving plant calcium concentrations along with NPK fertiliser application. However, in the second field experiment (with corrected soil nutrient deficiencies) the regression analysis generally showed that the root HCN levels of some cassava varieties could have been 'reduced' by improving either one or a combination of the nutrients phosphorous, zinc and potassium in plants along with NPK fertiliser application. Although the results obtained in the two experiments had been contradicting due to slight differences in how they were conducted, the study had nonetheless demonstrated the occurrence of meaningful relationships between plant nutritional status and cyanogenic glucoside production; confirming the possible use of plant tissue analysis in predicting fertiliser needs for the consistent attainment of low cyanogenic glucosides in cassava roots.


Assuntos
Fertilizantes , Glucosídeos/análise , Cianeto de Hidrogênio/análise , Manihot/química , Nitrilas/análise , Raízes de Plantas/química , Agricultura , Produtos Agrícolas/química , Cianetos/análise , Glicosídeos/análise , Concentração de Íons de Hidrogênio , Modelos Lineares , Nitrogênio/análise , Fósforo/análise , Potássio/análise , Solo
7.
Mar Pollut Bull ; 150: 110770, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31910523

RESUMO

Ornamental fish have been legally harvested since the 1930's but in the 60's, cyanide fishing was first documented. Target fish exposed to the chemical are temporarily paralysed making them easier to catch, but with high post-capture mortality and significant ecological impacts, its use is banned in most exporting countries. To differentiate illegally caught fish from those sustainably collected, efforts to develop a post-collection detection test began nearly 30 years ago. However, even the most promising approach has been questioned by other researchers as unrepeatable under different experimental conditions. In this paper we summarise the evidence-base for establishing a cyanide detection test for live fish by evaluating current approaches. We describe the key knowledge gaps which continue to limit our progress in implementing a screening programme and highlight some alternative solutions which may provide greater short to medium term opportunities to prevent the illegal practise before fish enter the supply chain.


Assuntos
Cianetos/análise , Monitoramento Ambiental , Alimentos Marinhos , Poluentes Químicos da Água/análise , Animais , Pesqueiros/estatística & dados numéricos , Peixes
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117974, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31927478

RESUMO

Colorimetric and fluorescent detection of cyanide and hydrogen sulfide ions has been effected using a simple organic probe in H2O:DMSO (20:80, v/v) medium. The probe exhibits a colour change from pale-yellow to red upon addition of these analytes under normal light and fluorescent change from green to red under UV lamp. Other competitive ions show no observable colour or fluorescence change. The binding constants of cyanide and hydrogen sulfide ions with the probe determined using fluorescence titration data are found to be 2.1 × 104 and 1.6 × 104 M-1, respectively. The probe fluorimetrically detects the analytes in a wide pH range (4-10). 1H and 13C NMR studies suggest that the probe senses cyanide ion through deprotonation and nucleophilic addition mechanism and hydrogen sulfide ion via deprotonation mechanism. Detection limits of cyanide and hydrogen sulfide are determined to be 0.15 and 1 µM, respectively. The practical utility of the probe has been demonstrated by same dual mode detection of cyanide in food materials like bitter almond, cassava flour and sprouting potato.


Assuntos
Colorimetria/métodos , Cianetos/análise , Sulfeto de Hidrogênio/análise , Iminas/química , Espectrometria de Fluorescência/métodos , Poluentes Químicos da Água/análise , Corantes Fluorescentes/química , Manihot/metabolismo , Prunus/metabolismo , Solanum tuberosum/metabolismo
9.
Environ Sci Pollut Res Int ; 27(8): 8176-8187, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31900767

RESUMO

The removal of cyanide compounds in soil by leaching was investigated in flask and column tests. All the experiments were conducted under alkaline conditions to prevent loss of hydrogen cyanide. Results showed that leaching progressed rapidly when the leaching temperature or the initial cyanide concentration was high. The obtained cyanide data in the flask test fitted an inner diffusion process, as described by a shrinking core model. In the batch column test, the cyanide concentration decreased from 44.06 to 9.86 mg/kg when the leaching intensity was 79 L/(m2 h) after 23.8 h leaching. The leaching process for the cyanide compounds was divided into two stages according to the batch column test despite the decrease in the leaching velocity as the cyanide concentration in soil declined. Cyanide removal in the batch column test was better than that in the flask test due to the higher gradient of cyanide concentration. The aqueous solution containing cyanide compounds was decomposed effectively by the hybrid process of ozone and UV rays. Furthermore, the leaching and decomposition of the soil and leaching wastewater were performed with a continuous column test with circulating leaching liquid. The cyanide compounds in the soil and wastewater were removed effectively.


Assuntos
Cianetos/análise , Poluentes do Solo , China , Cianetos/química , Solo , Águas Residuárias
10.
Anal Biochem ; 591: 113539, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31837297

RESUMO

A fluorescent probe that responds at distinct wavelengths upon exposure to cyanide, hypochlorite, and bisulfite was synthesized. As a result, an easy to apply analytical methodology was developed for the detection of these ions. The feasibility of this method was evaluated by theoretical calculations. The probe exhibited excellent solubility in the test solution (H2O: DMF = 99: 1, v: v) with low detection limits for cyanide, hypochlorite and bisulfite (4.5 × 10 -8 M, 4.9 × 10 -7 M and 4.3 × 10 -8 M respectively) showing distinct emission wavelengths for each ion without interference in practical application. Furthermore, the probe had low toxicity and was applied for the imaging experiments of cyanide, hypochlorite and bisulfite in living HeLa and MDCK cells.


Assuntos
Cianetos/análise , Corantes Fluorescentes , Ácido Hipocloroso/análise , Imagem Óptica , Sulfitos/análise , Água/química , Animais , Cães , Células HeLa , Humanos , Limite de Detecção , Células Madin Darby de Rim Canino
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117710, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31718964

RESUMO

Fluorescent sensor has been noticed in detecting system due to its sensitive, selective, operational simplicity and low cost. We designed a coumarin-connected carboxylic indolium sensor molecule that is water-soluble and cytomembrane-permeable. This infrared (IR) emitter is selectively sensitive towards cyanide detection in aqueous media according to CN- nucleophilic attack on the indole C=N function. Upon the addition of CN- anion, the color of sensor in water varied from blue to colorless by naked eyes and fluorescence quenching was observed by spectroscopic method. This was because the intramolecular charge transfer (ICT) effect occurred when the fluorescent sensor was added with CN-. The minimum detection limit of the sensor's fluorescence response to CN- is 4.44 × 10-7 mol/L. Furthermore, the cytotoxicity test shows the sensor has lower cytotoxicity, and indicates that this sensor can be utilized for practical detection of trace cyanide in wastewater.


Assuntos
Cumarínicos/química , Cianetos/análise , Indóis/química , Imagem Molecular , Água/química , Animais , Ânions , Morte Celular , Cumarínicos/síntese química , Indóis/síntese química , Melanoma Experimental/patologia , Camundongos , Modelos Moleculares , Espectroscopia de Prótons por Ressonância Magnética , Soluções , Espectrofotometria Ultravioleta
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117887, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31818646

RESUMO

A simple colorimetric receptor was synthesized by the condensation of 2-amino fluorene with 2-hydroxy-5-nitrobenzaldehyde and its properties were investigated using colorimetric, fluorescence and DFT studies. The sensing mechanism was ascertained by 1H NMR titration studies. The synthesized receptor showed two-pronged chemosensing properties and exhibited remarkable colorimetric transitions from colorless to yellow in the presence of CN- and colorless to green in the presence of Cu2+ in 80:20 acetonitrile/water medium, which could be determined by naked eye observations. The detection limit of receptor to CN- and Cu2+ ion was found to be 7.9 × 10-7 M and 4.5 × 10-8 M respectively. Receptor was also successfully employed in the construction of molecular INHIBIT and YES logic gates. The synthesized receptor was also efficiently used for real-sample analysis in Finger Millet, also known as Ragi in Tamil. Its scientific name is Eleusine coracana.


Assuntos
Cobre/análise , Cianetos/análise , Teoria da Densidade Funcional , Fluorenos/química , Lógica , Ânions , Cátions , Cinética , Limite de Detecção , Conformação Molecular , Espectroscopia de Prótons por Ressonância Magnética , Receptores Artificiais/química , Espectrometria de Fluorescência
13.
Talanta ; 207: 120278, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594612

RESUMO

Cyanide is potentially hazardous and quickly acting chemical used in many fields of industry. Therefore, detection of cyanide is of main health concern due to its serious impacts on living organisms. In this context, we have developed rapid, low-cost and on-site sensory two molecules for the colorimetric and fluorogenic sensing of cyanide ion in aqueous samples and food samples. The prepared probes undergo distinct visual color change and exhibits selective fluorogenic turn-on or turn-off response towards cyanide. Competing anions have little or negligible effect on the detection of cyanide. The limit of detection for cyanide ion was calculated as low as 0.45 µM. Free receptors could be successfully regenerated by treating them with Ag+ ion. Moreover, a new visual colorimetric strip based on paper was fabricated with the pale yellow-to-pink color change signal. The fabricated test strips also demonstrated excellent selectivity towards cyanide ion without interfering possible fluoride and acetate ions. The smartphone-based technique which could directly read out the color value using a smartphone revealed an excellent potential for the cyanide detection without additional device.


Assuntos
Colorimetria/economia , Colorimetria/instrumentação , Custos e Análise de Custo , Cianetos/análise , Corantes Fluorescentes/química , Smartphone , Cianetos/química , Limite de Detecção , Modelos Moleculares , Conformação Molecular , Fitas Reagentes/química , Fatores de Tempo , Água/química
14.
Anal Sci ; 36(2): 193-199, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31495817

RESUMO

A novel approach to building a membrane-based disposable well-plate, here applied to cyanide detection, is described. Chitosan encapsulated CdTe quantum dots with a maximum emission at 520 nm (CS-QD520) were used as fluorophores. The CS-QD520 nanoparticle was specifically quenched by copper(II), and the quenched CS-QD520 (Cu-CS-QD520) was deposited onto a glass microfiber filter (GF/B). Subsequent introduction of cyanide ion resulted in fluorescence recovery. The "signal-ON" fluorescence linearly correlated to cyanide concentrations in the range of 38.7 to 200 µM with a limit of detection of 11.6 µM. The assay was incorporated into a membrane-based well-plate format to enhance sample throughput. A three-layer paper/glass microfiber well plate design was cut using a laser cutter and assembled using a polycaprolactone (PCL) as a bonding agent in a low-cost laminator. The experimental conditions were optimized and applied to detect cyanide in drinking water with rapid, high-throughput, low-cost analysis.


Assuntos
Compostos de Cádmio/química , Quitosana/química , Cianetos/análise , Corantes Fluorescentes/química , Pontos Quânticos/química , Telúrio/química , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
15.
Chemosphere ; 239: 124707, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31479912

RESUMO

Site soils with persistent cyanide compounds (primarily iron-cyanide complex) pose potential hazards to the environment and require remediation before redevelopment. This study evaluated the possibility of thermal treatment on remediation of cyanide-contaminated soils via batch heating experiments spanning a wide temperature range (200-500 °C). The change with operation variables of total cyanide and some reaction intermediates (e.g. CN-) was analyzed in order to elucidate the optimal variables that guarantee cyanide removal while generating no hazardous byproducts. Temperature, heating time and cyanide species have been found to be important parameters influencing removal/destruction of cyanide in soils. For soils bearing K3[Fe(CN)6] and K4[Fe(CN)6], a removal efficiency of >99.9% can be obtained with temperatures over 350 °C at 1 h, while for samples bearing Fe4[Fe(CN)6]3, a higher temperature (>450 °C) is needed to obtain an equivalent efficiency. During heating, the iron-cyanide complexes decomposed, releasing highly toxic free cyanides, which will subsequently be oxidized. However, a small percentage of free cyanide can always be detected as a result of incomplete oxidation, thus caution should be taken to minimize the accumulation of free cyanide during thermal treatment.


Assuntos
Cianetos/análise , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/análise , Temperatura , Cianetos/química , Poluição Ambiental/prevenção & controle , Ferrocianetos/análise , Ferrocianetos/química , Oxirredução , Poluentes do Solo/química
16.
Ecotoxicol Environ Saf ; 189: 110015, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31830602

RESUMO

This paper adopts a novel data-processing method of ECSA® based on TG/DSC-MS system to basically study the characteristics of release and conversion of fluorides and cyanides during heat treatment of the spent cathode carbon block (SCCB). All the experiments were conducted at 10 K⋅min-1 heating rate and under Ar or Ar-O2 atmospheres. The results indicate that the release of fluorides was just a steady but slow phase transition process under both Ar and Ar-O2 atmospheres, which can be comparatively accelerated when the carbon material was burnt. The cyanides were effectively decomposed at high temperature and at Ar-O2 atmosphere, with around three quarters of the cyanides being converted to the N2 and nearly a quarter being to the NO. Finally, analysis on the flue gas composition indicates that it had a more complicated composition of CO2, N2, NO, NO2, HCN under Ar-O2 atmosphere but only had a composition of CO2 and NO under Ar atmosphere.


Assuntos
Poluentes Atmosféricos/química , Carbono/química , Cianetos/química , Eletrodos , Fluoretos/química , Poluentes Atmosféricos/análise , Alumínio , Argônio/química , Atmosfera/química , Cianetos/análise , Fluoretos/análise , Temperatura Alta , Metalurgia , Eliminação de Resíduos
17.
Chem Commun (Camb) ; 55(100): 15137-15140, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31789333

RESUMO

A fluorescent probe (TPA-BTD-MT) was designed to monitor cyanide ions (CN-) with a "turn-on" response, changing from "turn-off" behavior due to the structural change. TPA-BTD-MT exhibited high selectivity for sensing CN- in several food samples and was successfully used for imaging CN- in living cells and animals with strong "turn-on" fluorescence.


Assuntos
Cianetos/análise , Corantes Fluorescentes/química , Análise de Alimentos/métodos , Imagem Óptica , Compostos de Anilina/química , Animais , Linhagem Celular Tumoral , Limite de Detecção , Manihot/química , Manihot/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Teoria Quântica , Solanum tuberosum/química , Solanum tuberosum/metabolismo
18.
J Fluoresc ; 29(6): 1401-1410, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31755047

RESUMO

A quantitative and qualitative fluorogenic molecular probe (R) has been designed and synthesized using Rhodamine-B hydrazide and 3,5-dibromo salicylaldehyde. The probe R has been applied for detection of ionic species and probe R turned out to be a prominent distinguisher among divalent and trivalent cations Al3+, Cr3+ and Fe3+ via the fluorometric response in acetonitrile medium. Colorimetric changes were observed for trivalent cations and Cu2+. Among all trivalent cations, Al3+ is possessing relay recognition for CN- even in the presence of other interfering anions with optimum precision. The association constant and the detection limit for R-Al3+ are 4.5 × 106 M-1 and 17.9 nM respectively. On the other hand, R + Al3++CN- exhibits an association constant and detection limit of 5.77 × 105 M-1 and 4.6 nM respectively. The stoichiometry of Al3+ binding with R is found to be 1:1. Quantum efficiency of probe R, R + Al3+ and R + Al3++CN- are found to be 0.2, 0.88 and 0.04 respectively. The receptor showed excellent real-time applicability for commercially available antiperspirant and apple seeds extract. The efficiency of the receptor further extended for fluorescent imaging of Al3+ and CN- in RAW264.7 cells.


Assuntos
Alumínio/análise , Cianetos/análise , Corantes Fluorescentes/química , Imagem Óptica , Animais , Cinética , Camundongos , Células RAW 264.7 , Espectrometria de Fluorescência
19.
Leg Med (Tokyo) ; 41: 101628, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31711010

RESUMO

Cyanide poisoning has been regarded to contribute the fatal outcome in fire victims. The toxicity of inhaled hydrogen cyanide (HCN) at the cellular level was evaluated considering the impact of methemoglobin (MetHb) produced by fire gases. Cyanide (CN) concentrations and total hemoglobin contents were measured in right heart blood (RHB) and seven organs/tissues (basal ganglia, brain stem, heart, lung, liver, kidney and psoas muscle) collected from 20 fire fatalities. MetHb and carboxyhemoglobin saturations were also measured in RHB. The amount of CN probably bound to the cytochrome c oxidase of the tissue cells (CCO-CN) was extrapolated from CN and hemoglobin contents in RHB and organs/tissues, MetHb saturation in RHB and binding capacity of MetHb for CN. CN concentrations in RHB showed a wide range with the highest concentration of 8.927 µg/mL. The lung contained the largest CN content among organs/tissues with the mean concentration of 2.219 µg/g, then the heart (0.259 µg/g) and it was lower than 0.100 µg/g in others. Exceedingly large amount of CN in the lung could be explained by high hemoglobin content, being the port of entry of HCN and postmortem diffusion of fire gases. CCO-CN was theoretically present in about 20% of organ/tissue samples, most commonly in the basal ganglia (10 samples, with the mean of 0.059 µg/g) followed by heart (eight samples, with the mean of 0.109 µg/g). No CCO-CN was found in liver and kidney. HCN might have the effect on brain and heart.


Assuntos
Cianetos/análise , Incêndios , Adulto , Idoso , Idoso de 80 Anos ou mais , Gânglios da Base/química , Tronco Encefálico/química , Carboxihemoglobina/análise , Feminino , Medicina Legal , Hemoglobinas/análise , Humanos , Rim/química , Fígado/química , Pulmão/química , Masculino , Metemoglobina/análise , Pessoa de Meia-Idade , Miocárdio/química , Músculos Psoas/química , Adulto Jovem
20.
Analyst ; 144(21): 6422-6431, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31584578

RESUMO

Herein, a colorimetric sensor (L) based on a naphthyl derivative bearing hydrazone receptors was synthesized via a one-step reaction process, and its recognition properties towards biologically important anions in an acetonitrile-water mixture were investigated by naked-eye observation and UV-Vis and 1H NMR spectroscopy. The molar addition of anions, such as TBAF-, TBAOH-, TBACN- and TBAAcO-, induced a significant red shift in the charge transfer band (Δλ = 73 nm, from 337 nm to 410 nm), in agreement with visible "naked eye" detectable colorimetric activities; in addition, soaked-in-L paper strips were prepared, which could significantly discriminate cyanide (KCN) and hydroxide (NaOH) ions dissolved in tap water via the litmus test method. This study was complemented by density functional theory computations to gain more insight into the interaction between L and anions.


Assuntos
Colorimetria/métodos , Cianetos/análise , Água Potável/química , Hidróxidos/análise , Cianetos/química , Teoria da Densidade Funcional , Hidrazonas/química , Hidróxidos/química , Modelos Moleculares , Conformação Molecular , Fatores de Tempo
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