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1.
Talanta ; 281: 126894, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39303326

RESUMO

This work presents a simple and accurate method for the fast sequential determination of Rh, Pd, and Pt in spent automotive catalysts and e-wastes using high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS). Extensive research was carried out in model systems on the impact of potential interfering substances on analyte's signals measured in two types of flame (air-C2H2 and N2O-C2H2). Mutual analyte interactions were also taken into account. Different background corrections offered by the HR-CS AAS spectrometer were tested to obtain interference-free analyte signals and the best detectability. Using an air-C2H2 flame and 1 % La solution as a spectrochemical buffer provided good sensitivity and accurate determinations of Rh, Pd, and Pt using a simple calibration graph. Microwave-assisted leaching of PGE from waste samples with aqua regia at 240 °C for 60 min efficiently leached all target metals, which significantly simplified and shortened the sample preparation step. The detectability of the method (detection limit of 0.4, 0.6, and 5 mg kg-1 for Rh, Pd, and Pt, respectively) and precision (< 7 %) were satisfactory. The accuracy of the method was confirmed by analysis of certified reference materials (spent automotive catalyst (ERM-EB504), electronic scrap (BAM-M505a)), and calculated zeta score values. The recoveries for Rh, Pd, and Pt in ERM-EB504 were 93, 101, and 96 %, respectively, and for Pd in BAM-M505a, 97 %. The developed method can be used to assess the value of secondary raw materials, such as various types of spent catalysts and e-waste containing Rh, Pd, and Pt.

2.
Bull Environ Contam Toxicol ; 113(4): 42, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39306638

RESUMO

In the present paper, the assessment of vortex-assisted dispersive magnetic solid-phase extraction using amino-functionalized mesoporous combined with direct magnetic sorbent sampling (DMSS) in flame or furnace atomic absorption spectrometry (FAAS or FF-AAS) was demonstrated for highly sensitive silver determination in water samples. The developed method showed significant enrichment factors compared to conventional pneumatic nebulization by FAAS, 607 for DMSS-FF-AAS and 114 for DMSS-FAAS. The analytical curve showed linearity in the range from 5.0 to 70.0 µg L- 1 and 1.0 to 15.0 µg L- 1 and limits of detection of 0.59 and 0.09 µg L- 1 for DMSS-FAAS and DMSS-FF-AAS, respectively. The intra and inter-day precision evaluated as a percentage of the relative standard deviation (RSD,%) ranged from 1.89 to 4.71% for levels of 25.0 and 65.0 µg L- 1. The method was applied in different kinds of water samples without matrix effects, yielding recovery values from 90 to 110%.


Assuntos
Prata , Extração em Fase Sólida , Espectrofotometria Atômica , Poluentes Químicos da Água , Extração em Fase Sólida/métodos , Prata/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Limite de Detecção
3.
Food Chem ; 463(Pt 3): 141311, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39332356

RESUMO

MnAl layered double hydroxide hybrid with magnetic-multiwalled carbon nanotubes was synthesized by a hydrothermal method and used for the extraction of Pb(II) (lead) from spices and water samples in the dispersive solid phase microextraction (dSPµE) technique using FAAS. The as-prepared adsorbent MMWCNTs@MnAl-LDH was characterized by XRD, FTIR, EDX, and SEM techniques. Various analytical parameters were optimized, including pH 8, adsorbent dosage of 5 mg, HNO3 eluent concentration of 1 mol L-1, eluent volume of 3 mL, eluent time of 60 s, and sample volume of 20 mL, for quantitative lead recoveries, with an LOD of 0.314 µg L-1, an LOQ of 1.048 µg L-1, and PF of 11.53. Under the optimized conditions, the linearity ranges from 0.5 to 500 µg L-1 (R2 = 0.9997). For the validation test of the established dSPµE procedure, Certified reference materials (CRMs) were used, yielding satisfactory recovery results ranging from 97.8 to 102.7 %. The method was applied to determine lead in turmeric, tap water, and industrial water samples.

4.
MethodsX ; 13: 102863, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39157815

RESUMO

Purslane (Portulaca oleracea) and spinach (Spinacea oleracea) are species with elevated levels of oxalic acid, an antinutrient that interferes in the bioaccessibility of minerals such as calcium and iron. Evaluating methods to determine oxalic acid content with reduced matrix interference, such as employing Flame Atomic Absorption Spectrometry (FAAS), can enhance the specificity of determinations. The different matrices of purslane (whole plant, leaves, and juice) and spinach (whole plant) were tested using three extraction methods (M1, M2, and M3). The oxalic acid content was evaluated by UV-vis spectrophotometry and FAAS (Flame Atomic Absorption Spectrometry). The absence of the precipitation step in M1 resulted in high levels of oxalic acid in the investigated matrices. The quantification of oxalic acid by FAAS for M2 (6M HCl for 1 hour at 100°C) and M3 (0.25N HCl for 15 minutes at 100°C) in the samples of purslane leaves and spinach whole plants yielded statistically similar results. However, the analysis by UV-vis spectrophotometry for M2 and M3 showed significant discrepancies in all evaluated samples, suggesting interference from colored compounds in the food matrix.•Comparison of methods of extraction•Comparison of UV-vis spectrophotometer and FAAS in the quantification of oxalic acid•Analysis of antinutrients in plant matrices.

5.
Sensors (Basel) ; 24(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38793967

RESUMO

The arising of the Cyber-Physical Systems' vision and concepts drives technological evolution toward a new architectural design for the infrastructure of an environment referred to as a Smart Environment. This perspective alters the way systems within Smart City landscapes are conceived, designed, and ultimately realized. Modular architecture, resource-sharing techniques, and precise deployment approaches (such as microservices-oriented or reliant on the FaaS paradigm) serve as the cornerstones of a Smart City cognizant of multiple Cyber-Physical Systems composing it. This paper presents a framework integrating Digital Decisioning, encompassing the automated combination of human-derived knowledge and data-derived knowledge (e.g., business rules and machine learning), to enhance decision-making processes and application definition within the Smart City context.

6.
Foods ; 13(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38611369

RESUMO

Honey is well-known as a food product that is rich in active ingredients and is very popular among consumers. Free amino acids (FAAs) are one of the important nutritional components of honey, which can be used not only as a nutritional indicator of honey but also as an indicator of plant source identification. In this study, the contents of 20 FAAs in seven types of honey from 11 provinces in China were examined for the first time. The 20 FAAs were analyzed by ultra-performance liquid chromatography-mass spectrometry/mass spectrometry (UPLC-MS/MS). By analyzing 93 honey samples from seven types of honey, the FAAs were found to range from 394.4 mg/kg (linden honey) to 1771.7 mg/kg (chaste honey). Proline ranged from 274.55 to 572.48 mg/kg, and methionine was only present in some of the linden honey, chaste honey, acacia honey, and rape honey. Evaluated by amino acid principal component analysis, multifloral grassland honey had the highest overall evaluation score, acacia and jujube honey were the most similar, while chaste honey was the least similar to the other types of honey. In addition, DNA was extracted from 174 Xinjiang grassland honey samples and different plant leaves for PCR and sequencing to identify the species of nectar plants. As a result, 12 families and 25 species of honey plants were identified. The results confirmed the diversity of FAAs in dissimilar types and sources of honey. This study provides a reference for expanding honey quality standards and verifying the authenticity of honey.

7.
Anal Chim Acta ; 1296: 342308, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38401938

RESUMO

BACKGROUND: Determining metals in complex biological samples, such as milk, typically involves dry or wet decomposition. However, these techniques have limitations, including low selectivity, risk of contamination, and the use of large reagent volumes. To solve these problems, solid-phase extraction (SPE) using multifunctional sorbents has been extensively explored. In this context, this work proposed synthesizing a new restricted double access ionic imprinted polymer (RAIIP-BSA), for online SPE and determination of Cu2+ from untreated milk samples via flow injection analysis and flame atomic absorption spectrometry (FIA-FASS). RESULTS: Firstly, the polymer was obtained by bulk polymerization using Cu2+ as a template, 4-vinyl pyridine as a functional monomer, and glycidyl methacrylate as a hydrophilic comonomer. Subsequently, it was covered with bovine serum albumin, creating the restricted double access barrier. The obtained material could exclude 97 % of the proteins from milk samples. RAIIP-BSA was chemically and physically characterized. The main extraction variables were optimized via multivariate optimization. The method showed good figures of merit, such as linearity ranging from 0.05 to 1.0 mg L-1, LoD and LoQ of 0.03 and 0.05 mg L-1, intra- and interday precision ranging from 0.73 to 4.14 % and 0.16-3.68 %, and an intra- and interday accuracy ranging from 97.0 to 115.0 % and 103.0-119.0 %, respectively. SIGNIFICANCE: The developed method demonstrates the effective extraction of Cu2+ from untreated milk samples, exhibiting selectivity, high extraction capacity, prolonged sorbent (RAIIP-BSA) durability, simplicity, and swift operation. This method holds promise as an alternative to conventional metal analysis approaches in complex matrices.


Assuntos
Cobre , Impressão Molecular , Animais , Cobre/química , Leite/química , Impressão Molecular/métodos , Polímeros/química , Extração em Fase Sólida/métodos
8.
Food Addit Contam Part B Surveill ; 16(4): 375-383, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37746844

RESUMO

This study aimed to determine the content of elemental levels of eight plants species originating from Mauritania and used as medicinal plant and to assess their risk for human health. The range of elemental content in the studied plant parts of these plant species were 0.51-16.1 mg/g for Ca, 2.63-6.49 mg/g for Mg, 11.2-201 µg/g for Al, 6.5-28.2 µg/g for Zn, 5.6-453 µg/g for Fe, 1.1-6.4 µg/g for Ni, 11.0-302 µg/g for Mn and 0.7-9.0 µg/g for Cu. The Cr, Pb, Cd and Co levels were below the limits of detection in all samples. The estimated weekly intake (EWI) and target hazard quotient (THQ) were calculated. Except for Al the THQ values were below 1, so it could be concluded that these plant species have low probability of causing non-cancer health problems for the consumer.


Assuntos
Metais Pesados , Oligoelementos , Humanos , Oligoelementos/análise , Mauritânia , Contaminação de Alimentos , Medição de Risco , Monitoramento Ambiental , Metais Pesados/análise
9.
Environ Sci Pollut Res Int ; 30(36): 85903-85909, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37395883

RESUMO

The concentrations of potentially toxic metals like lead (Pb), cadmium (Cd), and mercury (Hg) in healthy lactating mothers of Lahore city were estimated during 2020-2021 with the help of a flame atomic absorption spectrometer (FAAS). Seventy samples of breast milk were collected from two different age groups, namely, G-1 (25-30 years) and G-2 (31-40 years). The results showed that Cd contents were below the detection limit of the measuring instrument; however, the Pb and Hg contents were detected with great ease. The mean concentrations of Pb and Hg in the G-1 corresponding to the age between 25 and 30 years were observed to be 1.914 ± 0.493 µg/L and 10.432 ± 3.249 µg/L, respectively. For the G-2 with an age limit between 31 and 40 years, the concentrations of Pb and Hg were estimated to be 2.045 ± 0.502 µg/L and 11.527 ± 3.231 µg/L, respectively. The T-test analysis of concentrations of these toxic metals indicated a significant correlation between the content levels of Pb and Hg (p < 0.05). The observed values of toxic metals were significantly more frequent than those suggested by WHO (World Health Organization). An increase in the concentrations of Pb and Hg is directly associated with the location of the target population. As a result, it is turned out that the majority of the lactating woman with significantly high levels of Pb and Hg belongs to industrial areas of Lahore. To avoid such conditions, residential areas must be at larger distances, in addition, to strictly abiding by the environmental policies of the government.


Assuntos
Mercúrio , Metais Pesados , Humanos , Feminino , Adulto , Leite Humano/química , Cádmio/análise , Chumbo/análise , Lactação , Paquistão , Mercúrio/análise , Intoxicação por Metais Pesados , Metais Pesados/análise
10.
Nutrients ; 15(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37375717

RESUMO

The aim of this study was to determine the potential relative bioaccessibility of zinc (Zn) from selected dietary supplements during in vitro digestion. The bioaccessibility of Zn was evaluated in dietary supplements differing in the pharmaceutical form, content, dose, and chemical form of the element. The content of Zn was determined by flame atomic absorption spectrometry. The applied method was validated, and results were characterised by good linearity (R2 = 0.998), recovery (109%), and accuracy (0.02%). As a result of the tests conducted, it was found that the bioaccessibility of Zn from dietary supplements varied and ranged from 1.1% to 9.4%. The highest bioaccessibility was found for zinc diglycinate and the lowest for zinc sulphate. In 9 out of 10 tested dietary supplements, the determined Zn content was higher than the one declared by the producer (up to 161%). The estimated tolerable upper intake level (UL) was exceeded by five of the analysed dietary supplements (123-146%). The analysed dietary supplements were assessed in terms of compliance with the information contained on the product packaging, based on current Polish and European legal regulations. The qualitative assessment was performed according to the United States Pharmacopoeia (USP) guidelines.


Assuntos
Suplementos Nutricionais , Zinco , Suplementos Nutricionais/análise , Sulfato de Zinco , Projetos de Pesquisa , Preparações Farmacêuticas
11.
Environ Monit Assess ; 195(7): 861, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37335378

RESUMO

In order to eliminate the effects of seawater matrix on the precise/accurate determination of elements, new and efficient analytical procedure requires. In this study, co-precipitation method based on the triethylamine (TEA)-assisted Mg(OH)2 was performed to eliminate side-effects of seawater medium on the determination with flame atomic absorption spectrometry (FAAS) prior to the preconcentration of nickel by an optimized dispersive liquid-liquid microextraction (DLLME) method. Under the optimum conditions of the presented method, the limit of detection and quantification (LOD, LOQ) values obtained for nickel were found as 16.1 and 53.8 µg kg-1, respectively. Seawater samples collected from West Antarctic region were used for real sample applications to check the accuracy and applicability of developed method, and satisfying recovery results (86-97%) were obtained. In addition to this, the digital image-based colorimetric detection system and the UV-Vis system were applied to confirm the applicability of the developed DLLME-FAAS method in other analytical systems.


Assuntos
Microextração em Fase Líquida , Níquel , Níquel/análise , Microextração em Fase Líquida/métodos , Monitoramento Ambiental/métodos , Água do Mar , Limite de Detecção , Espectrofotometria Atômica/métodos
12.
Harmful Algae ; 125: 102422, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37220975

RESUMO

Phytoplankton composition is an important factor affecting the growth and physiological biochemical characteristics of filter-feeding bivalves. With the increasing trend in dinoflagellate biomass and blooms in mariculture areas, how the physio-biochemical traits and seafood quality of the mariculture organism are affected by the dinoflagellates, especially those at nonfatal levels, is not well understood. Different densities of two Karlodinium species, namely K. veneficum (KV) and K. zhouanum (KZ), mixed with high quality microalgal food Isochrysis galbana was applied in feeding manila clam Ruditapes philippinarum in a 14-day temporary culture, to comparatively study how the critical biochemical metabolites such as glycogen, free amino acids (FAAs), fatty acids (FAs), volatile organic compounds (VOCs) in the clam were affected. The survival rate of the clam showed dinoflagellate density and species specificity. The high-density KV group inhibited survival to 32% lower than that of the pure I. galbana control, respectively, while KZ at low concentrations did not significantly affect the survival compared with the control. In the high-density KV group, the glycogen and FAA contents decreased (p < 0.05), indicating that energy and protein metabolism were significantly affected. Amount of carnosine (49.91 ± 14.64 to 84.74 ± 8.59 µg/g of muscle wet weight) was detected in all the dinoflagellate-mixed groups, while it was not present in the field samples or in the pure I. galbana control, showing that carnosine participated in the anti-stress activities when the clam was exposed to the dinoflagellates. The global composition of FAs did not significantly vary among the groups. However, contents of the endogenous C18 PUFA precursors linoleic acid and α-linolenic acid significantly decreased in the high-density KV group compared to all the other groups, indicating that high density of KV affected the metabolisms of fatty acids. From the results of the changed VOC composition, oxidation of fatty acids and degradation of free amino acids might occur in the clams exposed to dinoflagellates. The increased VOCs, such as aldehydes, and decreased 1-octen-3-ol probably produced a more fishy taste and reduced food flavor quality when the clam was exposed to the dinoflagellates. This present study demonstrated that the biochemical metabolism and seafood qulity of the clam were affected. However, KZ with moderate density in the feed seemed to be beneficial in aquaculture for increasing the content of carnosine, a high-valued substance with multiple bioactivities.


Assuntos
Bivalves , Carnosina , Dinoflagellida , Microalgas , Animais , Aminoácidos , Ácidos Graxos , Glicogênio
13.
Food Sci Nutr ; 11(3): 1572-1583, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36911834

RESUMO

A novel probiotic Pediococcus acidilactici AS185, isolated from traditional Chinese fermented foods, was used as an adjunct culture for probiotic cheddar cheese production. The physicochemical composition, textural, free amino acids (FAAs), short-chain fatty acids (SCFAs) profiles, sensory properties, and microbial survival, was evaluated during the 90-day ripening period. The addition of P. acidilactici AS185 did not influence the physicochemical composition of cheddar cheese but significantly decreased the hardness without affecting its textural profile. During ripening, P. acidilactici AS185 was able to grow and promote the generation of FAAs and SCFAs, but did not alter the overall sensory properties; it rather improved the flavor and taste of cheese. In addition, the cheese matrix protected strain P. acidilactici AS185 during transit throughout the simulated gastrointestinal system. These results demonstrated that P. acidilactici AS185 adjunct cultures might be useful for producing high-quality probiotic cheddar cheese.

14.
Food Chem X ; 17: 100584, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36845502

RESUMO

This study investigated the effects of different cooking methods on non-volatile flavor (free amino acids, 5'-nucleotides, and organic acids, etc.) of Coregonus peled meat. The volatile flavor characteristics were also analyzed by electric nose and gas chromatography-ion migration spectrometry (GC-IMS). The results indicated that the content of flavor substances in C. peled meat varied significantly. The electronic tongue results indicated that the richness and umami aftertaste of roasting were significantly greater. The content of sweet free amino acids, 5'-nucleotides, and organic acids was also higher in roasting group. Electronic nose principal component analysis can distinguish C. peled meat cooked (the first two components accounted for 98.50% and 0.97%, respectively). A total of 36 volatile flavor compounds were identified among different groups, including 16 aldehydes, 7 olefine aldehydes, 6 alcohols, 4 ketones, and 3 furans. In general, roasting was recommended and gave more flavor substances in C. peled meat.

15.
Talanta ; 257: 124297, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36796173

RESUMO

In this study, a miniaturized liquid-liquid extraction (LLE) method for pre-concentration of Na, K, Ca, and Mg in crude oil was proposed. Analytes in crude oil were quantitatively extracted to the aqueous phase, followed by flame atomic absorption spectrometry (FAAS) determination. The following parameters were evaluated: type of extraction solution, sample mass, heating temperature and time, stirring time, centrifugation time, and the use of toluene and chemical demulsifier. Accuracy was evaluated by comparing the results obtained by the proposed method (LLE-FAAS) with those obtained after high-pressure microwave-assisted wet digestion and FAAS determination (reference values). No statistical difference was observed between the reference values and those using the optimized conditions for LLE-FAAS: 2.5 g of sample; 1000 µL of 2 mol L-1 HNO3, 50 mg L-1 of chemical demulsifier in 500 µL of toluene, 10 min of heating at 80 °C, 60 s of stirring, and 10 min of centrifugation. Relative standard deviations were lower than 6%. The limits of quantification (LOQ) were 1.2, 1.5, 5.0, and 0.50 µg g-1 for Na, K, Ca, and Mg, respectively. The proposed miniaturized LLE method presents several advantages, such as ease-of-use, high throughput (up 10 samples can be processed per 1 h), uses a high sample mass reaching low LOQs. In addition, the use of a diluted solution for extraction reduces the amount of reagents (around 40 times) and consequently laboratory residue generation, becoming an environmental friendly method. Suitable LOQs were achieved for analyte determination at low concentration even using a simple and low-cost sample preparation system (miniaturized LLE method) and a relatively low-cost determination technique (FAAS), avoiding the use of microwave ovens and more sensitivity techniques, which are required for routine analyses.

16.
Food Chem ; 413: 135676, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36804744

RESUMO

The direct magnetic sorbent sampling flame atomic absorption spectrometry (DMSS-FAAS), recently proposed by our research group, was applied to determine the lead in soy-based juice, whole grape juice, reconstituted grape juice, and orange nectar samples. A dispersive solid phase extraction (d-SPE) of lead was carried out using a magnetic orange peel powder, developed and optimized by Gupta et al (2012), that was inserted into flame by FAAS with a magnetic probe. The limits of quantification (<4.6 µg L-1) were smaller than maximum residue limits established in Brazil. Good precisions and accuracies were obtained. DMSS-FAAS presented a sensitivity at least 14 times greater than the d-SPE followed by conventional FAAS analysis, wherein the analytes were extracted and desorbed, and the eluate was introduced in FAAS via nebulization system. Lead was easily quantified in juice samples at very low concentrations, with satisfactory figures of merit, and without the need of a mineralization step.


Assuntos
Magnetismo , Extração em Fase Sólida , Espectrofotometria Atômica/métodos , Extração em Fase Sólida/métodos , Alimentos , Fenômenos Magnéticos
17.
Environ Monit Assess ; 195(2): 313, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36662307

RESUMO

In this study, a green, simple and effective preconcentration method named as spray-assisted fine droplet formation-liquid phase microextraction (SAFDF-LPME) before the flame atomic absorption spectrophotometry (FAAS) measurement for cobalt determination was developed. The method reduces the external dispersive solvent usage by using a simple spraying apparatus to obtain fine droplets of the extraction solvent. SAFDF-LPME method also consists of simultaneous complexation and extraction which indicates the environmental benevolence of the developed method. This method minimized the relative errors with high repeatability and accuracy by reducing the experimental steps. The influential parameters such as buffer type, buffer solution volume, extraction solvent/ligand solution volume (spraying cycle), and mixing period were systematically optimized by the univariate optimization procedure. With the optimum parameters applied, the detection power of the FAAS system was enhanced to about 110-folds with respect to 2.2 ng mL-1 detection limit calculated for the proposed method. Bottled drinking water samples from Fiji Islands were used to demonstrate the applicability of the developed method for the accurate determination of trace cobalt in real sample matrices. Percent recovery results obtained between 95.5 and 88.5% showed the suitability of the developed method in the determination of cobalt at trace levels even in complex sample matrices.


Assuntos
Água Potável , Microextração em Fase Líquida , Poluentes Químicos da Água , Espectrofotometria Atômica/métodos , Microextração em Fase Líquida/métodos , Cobalto/análise , Fiji , Quartzo , Limite de Detecção , Monitoramento Ambiental/métodos , Solventes , Poluentes Químicos da Água/análise
18.
Environ Monit Assess ; 195(2): 309, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36652146

RESUMO

This study presents a simple, sensitive, and accurate method for the determination of nickel by flame atomic absorption spectrometry (FAAS). Prior to instrumental measurement, a deep eutectic solvent-based simultaneous complexation and preconcentration (DES-SCP) method was used to preconcentrate nickel from aqueous solution into measurable quantities. The efficiency of the extraction method was enhanced by forming a non-ionic complex of nickel using dithizone as ligand. By mixing the ligand with the DES extractant, simultaneous complexation and preconcentration of nickel were achieved in a single step. Under optimum conditions of the extraction method, the limit of detection (LOD) and the limit of quantification (LOQ) values were found to be 2.4 and 8.0 ng/mL, respectively. With respect to direct FAAS measurement, the developed method enhanced the sensitivity of nickel determination by about 169 folds. The accuracy and applicability of the developed method were evaluated by performing spike recovery experiments with lake water sampled from Antarctica. Satisfactory recovery results in the range of 94.0-113.7% were recorded and this validated the developed method as an efficient and green alternative for nickel determination.


Assuntos
Microextração em Fase Líquida , Níquel , Solventes/química , Níquel/análise , Regiões Antárticas , Solventes Eutéticos Profundos , Espectrofotometria Atômica/métodos , Lagos/análise , Ligantes , Microextração em Fase Líquida/métodos , Monitoramento Ambiental/métodos , Água/análise
19.
Biol Trace Elem Res ; 201(8): 3645-3657, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36355263

RESUMO

Laryngeal cancer, a rare form of head and neck cancer, is more common in men, and various factors play important roles in its etiology. In the current study, trace elemental contents in the scalp hair of laryngeal cancer patients and healthy subjects were evaluated. Selected essential and toxic elements were measured using flame atomic absorption spectrophotometry after the hair samples were digested with HNO3-HClO4. The mean/median levels of Pb in the scalp hair of patients were significantly higher than the healthy donors, but Sr, Zn, and Co exhibited comparatively lower levels in the laryngeal cancer patients. In comparison to healthy donors, the correlation pattern among the elements in the hair of the patients exhibited diverse mutual relationships. The multivariate apportionment of the elemental levels in the scalp hair of both donor groups was significantly divergent. The average elemental levels varied significantly among the cancer types (glottic, supraglottic, transglottic, and subglottic) as well as the cancer stages (I, II, III, IV). The average levels of the elements also exhibited considerable variations depending on the donors' habitat, gender, food, and smoking habits. Overall, the study revealed significantly divergent disparities among the elemental contents in the scalp hair of the laryngeal cancer patients in comparison with counterpart controls.


Assuntos
Neoplasias Laríngeas , Oligoelementos , Masculino , Humanos , Couro Cabeludo/química , Cabelo/química , Oligoelementos/análise , Fumar , Espectrofotometria Atômica
20.
Biometals ; 36(1): 111-127, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36370262

RESUMO

Laryngeal carcinoma is one of the common types of head and neck cancer, with men being more likely than women to develop it. Diet, age, gender, smoking habits, and environmental factors play important roles in its development. The goal of this study was to ascertain if there were imbalances in essential and toxic trace metals owing to the initiation and progression of laryngeal cancer. Atomic absorption spectrometry was employed to quantify selected macroelements, and essential/toxic trace metals in blood of the cancerous patients and matching controls. Significantly higher concentrations of Pb, Cu, Fe, and Sr while substantially lower levels of Na, K, Ca, and Mg were observed in the cancer patients compared with the controls. Considerably disparate mutual relationships among the macroelements, and essential/toxic trace metals in the patients and controls were manifested by their correlation coefficients. Similarly, multivariate apportionment of the metal levels showed appreciably diverse associations and grouping in the patients and controls. The laryngeal cancer patients exhibited significant disparities in the metal levels among various sub-types (supraglottic, subglottic, transglottic, and glottic cancer) and stages (I, II, III, and IV) of the disease. Most of the metals revealed distinct differences based on the gender, habitat, age, eating preferences, and smoking habits in both donor groups. Overall, the study demonstrated significant imbalances among the macroelements, and essential/toxic trace metal levels in the blood of laryngeal cancer patients compared to the controls.


Assuntos
Neoplasias Laríngeas , Oligoelementos , Masculino , Humanos , Feminino , Metais , Dieta , Oligoelementos/análise , Espectrofotometria Atômica
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