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1.
Food Chem ; 442: 138492, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38245986

RESUMEN

In this work, we propose a novel approach for extracting Cu and Ni from vegetable oils (which can be expanded to other metals). The method is based on the transference of the analytes to an aqueous acid phase due to the disruption of a three-component solution. The extraction was carried out in two steps. In the first step, a three-component solution was prepared comprising the sample, 1-octanol, and HNO3 solution. Next, the homogeneous system was disrupted by adding 1.0 mL of deionized water, and two phases were formed. The aqueous extract deposited in the bottom of the flask was collected with a micropipette, and Cu and Ni were determined by graphite furnace atomic absorption spectrometry (GF AAS). The developed method presented limits of quantification (LOQ) of 0.25 and 0.17 ng g-1 for Cu and Ni, respectively, and was successfully applied in the analysis of eleven oil samples from different origins.


Asunto(s)
Grafito , Aceites de Plantas , Aceites de Plantas/química , Grafito/química , Espectrofotometría Atómica/métodos , Agua/química
2.
Appl Radiat Isot ; 205: 111184, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38215645

RESUMEN

Boron neutron capture therapy (BNCT) combines neutron irradiation with boron compounds that are selectively uptaken by tumor cells. Boronophenylalanine (BPA) is a boron compound used to treat malignant brain tumors. The determination of boron concentration in cells is of great relevance to the field of BNCT. This study was designed to develop a novel method for simultaneously measuring the uptake of BPA by U87 and U251 cells (two brain tumor cell lines) and number of cells using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The results revealed a linear correlation between phosphorus intensity and the numbers of U87 and U251 cells, with correlation coefficients (R2) of 0.9995 and 0.9994, respectively. High accuracy and reliability of phosphorus concentration standard curve were also found. Using this new method, we found that BPA had no significant effect on phosphorus concentration in either U87 or U251 cells. However, BPA increased the boron concentration in U87 and U251 cells in a concentration-dependent manner, with the boron concentration in U87 cells being higher than that in U251 cells. In both U87 and U251 cells, boron was mainly distributed in the cytoplasm and nucleus, accounting for 85% and 13% of the total boron uptake by U87 cells and 86% and 11% of the total boron uptake by U251 cells, respectively. In the U87 and U251 cell-derived xenograft (CDX) animal model, tumor exhibited higher boron concentration values than blood, heart, liver, lung, and brain, with a tumor/blood ratio of 2.87 for U87 cells and 3.11 for U251 cells, respectively. These results suggest that the phosphorus concentration in U87 and U251 cells can represent the number of cells and BPA is easily uptaken by tumor cells as well as in tumor tissue.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Neoplasias Encefálicas , Animales , Humanos , Espectrofotometría Atómica , Boro , Reproducibilidad de los Resultados , Neoplasias Encefálicas/radioterapia , Encéfalo , Compuestos de Boro , Fósforo , Terapia por Captura de Neutrón de Boro/métodos
3.
Food Chem ; 439: 138140, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38061298

RESUMEN

Rose tea infusion has gained popularity worldwide due to its health benefits. However, it is known that tea plants can be contaminated with heavy metals including copper. Hence, an accurate and applicable analytical method namely emulsification liquid-liquid microextraction based deep eutectic solvent - flame atomic absorption spectrometry (ELLME-DES-FAAS) was proposed to determine copper at trace levels in rose tea samples. Under the optimum experimental conditions, analytical figures of merit for the developed method were examined, and dynamic range, limit of detection (LOD) and limit of quantification (LOQ) were found to be 5.07-246.61 µg/kg (mass-based) with 0.9992 coefficient of determination, 2.50 µg/kg and 8.32 µg/kg, respectively. A matrix matching calibration strategy was employed to boost recovery results, and the acceptable recovery results were recorded between 95.9 % and 118.4 %. According to recovery results, the developed analytical method can be safely employed to determine the concentration of copper in rose tea samples accurately.


Asunto(s)
Microextracción en Fase Líquida , Contaminantes Químicos del Agua , Cobre/análisis , Microextracción en Fase Líquida/métodos , Espectrofotometría Atómica/métodos , Análisis de los Alimentos/métodos , Solventes/química , Límite de Detección , Té/química , Contaminantes Químicos del Agua/análisis
4.
Food Chem ; 441: 138243, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38159436

RESUMEN

In the present study, a green and sensitive analytical method for the determination of copper ion at trace levels in apple tea samples was developed. Simultaneous complexation/extraction of the analyte were achieved by spraying-based fine droplet formation liquid-phase microextraction (SFDF-LPME). Copper ion was complexed with a Schiff base chelating agent called as N,N'-Bis(salicylidene)-1,2-phenylenediamine (BSP). Under the optimum conditions, the developed SFDF-LPME-FAAS and FAAS system were assessed with respect to limit of detection (LOD), limit of quantitation (LOQ), linearity and percent relative standard deviation (%RSD). LOD and LOQ values for SFDF-LPME-FAAS method were found to be 6.0 and 19.9 µg/kg, respectively. Enhancement in calibration sensitivity for developed method was found as 23 folds. In addition, accuracy/suitability of the developed SFDF-LPME-FAAS method were confirmed by spiking experiments. Two different apple tea samples were spiked to different concentration values and percent recovery results from 91.1 and 123.8 % proved the accuracy/suitability of the method.


Asunto(s)
Microextracción en Fase Líquida , Malus , Cobre/análisis , Espectrofotometría Atómica/métodos , Cuarzo , Límite de Detección , Microextracción en Fase Líquida/métodos ,
5.
Food Chem ; 429: 136862, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37478598

RESUMEN

In this study, a magnetic sorbent assisted dispersive solid phase extraction (DSPE) method was used to preconcentrate lead ions from rooibos tea samples for determination by slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS). Cobalt ferrite magnetic nanoparticles (CoFe2O4 MNPs) were synthesized by microwave assisted digestion. Limits of detection and quantification were calculated as 5.3 and 17.6 µg/L, respectively, in a linear dynamic range of 20-800 µg/L. The enhancement factor of the developed method was found to be 80-folds when compared to the detection limit of the regular FAAS system. The percent recoveries obtained for rooibos tea samples spiked at different concentrations were in the range of 77 - 125%, with high repeatability as indicated by low standard deviations. The findings of the study demonstrated that the CoFe2O4 MNPs-based extraction method is a straightforward, fast, affordable, safe, and eco-friendly approach to qualifying/quantifying lead with high precision in the selected beverage sample.


Asunto(s)
Aspalathus , Microextracción en Fase Líquida , Nanopartículas , Microondas , Microextracción en Fase Líquida/métodos , Espectrofotometría Atómica/métodos , Té/química
6.
J Trace Elem Med Biol ; 78: 127171, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37156091

RESUMEN

OBJECTIVE: Zinc is an essential trace element, being a cofactor for almost 300 enzymes. As zinc is widely available in the diet, the European Best Practice Guidelines do not recommend routine supplementation in dialysis patients. However, some medicines prescribed to dialysis patients may potentially reduce absorption, and there may be increased losses with dialysis. As older and co-morbid patients are now treated by peritoneal dialysis (PD) we wished to determine the prevalence of patients with low plasma zinc levels. DESIGN AND METHODS: We prospectively measured plasma zinc in 550 PD patients attending for their first peritoneal membrane assessment using atomic absorption spectroscopy. Body composition was determined by bioimpedance. RESULTS: Plasma zinc was measured in 550 patients, mean age 58.7 years, 60.6% male, mean value 10.8 ± 2.2 umol/L, with 66.5% having low zinc levels (<11.5 umol/L). Normal plasma zinc was associated with haemoglobin (odds ratio (OR) 1.41 (95% confidence limits (95%CL) 1.22-1.63), serum albumin (OR 1.04 (95%CL 1.002-1.087), higher glucose dialysates L/day (OR 1.06 (1.001-1.129), and negatively with 24-hour urinary protein losses (OR 0.786 (95%CL 0.673-0.918) and age (OR 0.985 (95%CL 0.972-1.0). There was no association with dialysis adequacy, original renal disease or dietary protein estimation. Prescription of phosphate binders had no effect on zinc levels (10.7 ± 2.2 vs 10.8 ± 2.3 umol/L). CONCLUSIONS: Most PD patients had low plasma zinc levels, associated with older age, probably reflecting reduced intake, urinary protein losses, and lower albumin and haemoglobin most likely linked to greater co-morbidity, low grade inflammation and volume expansion requiring higher glucose dialysates.


Asunto(s)
Diálisis Peritoneal , Oligoelementos , Zinc , Prevalencia , Zinc/sangre , Oligoelementos/sangre , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Espectrofotometría Atómica , Soluciones para Diálisis/química
7.
Anal Methods ; 15(16): 2030-2038, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-37060114

RESUMEN

Over the last years, inductively coupled plasma mass spectrometry (ICP-MS) has been applied as a method for human-biomonitoring of metals in the concentration range of occupational and environmental medicine. In large scale routine monitoring, the determination of mercury (Hg) by ICP-MS remains challenging due to several reasons. Amongst others, stability of dissolved Hg and avoiding memory effects are the key facts for reliable quantification. To address these issues, we developed a robust approach for biomonitoring of mercury in human urine samples by ICP-MS. Using a solution containing HNO3, HCl and thiourea, prepared samples and calibrators were stabilized for up to 72 h. A rinse time of only 30 seconds efficiently prevented contamination of consecutive samples with Hg concentrations up to 30 µg L-1, hence significantly reducing acquisition times compared to published methods. Recovery experiments revealed iridium as an ideal internal standard to compensate matrix effects independently from creatinine concentration. Recoveries of 95.0-104.0% were obtained for Hg levels covering the range of biomonitoring guidance values established by the German Human-Biomonitoring Commission. Excellent intra-day precision and inter-day precision of ≤3.0% for two different Hg levels were achieved. The detection and quantification limit accounted for 21.7 ng L-1 and 65.6 ng L-1, respectively, enabling reliable quantification even in the range of environmental background exposures. Additionally, the method was externally validated by successful participation in the inter-laboratory comparison program G-EQUAS. With the developed method, we hence provide a sensitive and robust tool for mercury exposure assessments in future large scale human-biomonitoring studies.


Asunto(s)
Mercurio , Humanos , Mercurio/orina , Tiourea , Monitoreo Biológico , Espectrofotometría Atómica/métodos , Espectrometría de Masas/métodos
8.
Environ Sci Pollut Res Int ; 30(9): 24553-24561, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36344888

RESUMEN

Today, drug dealers and sellers add lead compounds to these substances to get more profit. As a result, drug users are heavily exposed to lead, and lead poisoning is clearly seen in most of them. Therefore, it is especially important to check the blood lead levels in these people. In this research, an efficient and eco-friendly pretreatment method was established by deep eutectic solvent for dispersive liquid-liquid microextraction (DES - DLLME) followed by graphite furnace atomic absorption spectrometry (GFAAS) analysis. The selected hydrophilic deep eutectic solvent consists of l-menthol and (1S)-( +)-camphor-10-sulfonic acid (CSA) at a 5:1 molar ratio as a green solvent instead of traditional toxic organic solvents. Under the optimal extraction conditions, the introduced method exhibited good linearity with coefficient of determination (r2) 0.9975 and an acceptable linear range of 0.3-80 µg L-1. Accordingly, the detection limit was 0.1 µg L-1 (S/N = 3) for lead ions, and the high enrichment factor (240) was obtained. The proposed method was successfully applied to analysis lead ions in real blood samples, which is a promising technique for biological samples. The case samples were classified and analyzed based on age, duration of consumption, and type of substance. The results showed that there was no significant difference between blood lead levels in different age groups and different duration of use, while blood lead levels were higher in opium residue (shireh) users than in opium users.


Asunto(s)
Grafito , Microextracción en Fase Líquida , Humanos , Solventes/química , Plomo/análisis , Grafito/análisis , Opio/análisis , Disolventes Eutécticos Profundos , Microextracción en Fase Líquida/métodos , Espectrofotometría Atómica/métodos , Grupos Control , Límite de Detección
9.
Biol Trace Elem Res ; 201(8): 4143-4155, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36355264

RESUMEN

Diversity in eleven Artemisia species from northern Pakistan was assessed based on as per suitability of their elemental contents with thermal conductivity detection and ICP-AES procedures. Results indicated the presence of 13 major elements in the Artemisia species with varied concentrations including Carbon (45.7%, 45,7000 ppm-49.8%, 49,8000 ppm), Nitrogen (2.03%, 20,300 ppm-3.50%, 35,000 ppm), Phosphorus (0.168%, 1680 ppm-0.642%, 6420 ppm), Potassium (2.38%, 23,800 ppm-4.72%, 47,200 ppm), Sulphur (1920 ppm, 0.192%-4780 ppm, 0.478%), Boron (23.8 ppm, 0.00238%-71.7 ppm, 0.00717%), Calcium (0.733%, 7330 ppm-2.249%, 22,490 ppm), Magnesium (0.116%, 1160 ppm-0.267%, 2670 ppm), Zinc (27.7 ppm, 0.00277%-47.9 ppm, 0.00479%), Manganese (25.7 ppm, 0.00257%-93.8 ppm, 0.00938%), Iron (353 ppm, 0.0353%-1532 ppm, 0.1532%), Copper (14.1 ppm, 0.00141%-26.2 ppm, 0.00262%) and Sodium (105 ppm, 0.0105%-587 ppm, 0.0587%). Cluster analysis distributed the Artemisia species into two major groups (G1 and G2) on the basis of their elemental content where G1 contained species like, Artemisia herba alba Asso., A. tournefortiana Rachb., A. rutifolia Steph. ex Spreng., and A. vulgaris L., with the presence of all elements with the maximum amount of S, Zn, P, Ca, and Mg, while G2 contained species like Artemisia biennis Willd., A. chamaemelifolia Vill., A. capillaris, L., A. gmelinii Weber ex Stech., A. indica Willd., A. maritima L., and A. verlotiorum Lamotte., with all elements but significant concentrations of B, N, C, K, Mn, Fe, Cu, and Na. PCA analysis displayed maximum species diversity in the axes two, while axes one showed lower diversity. Additionally, the elevated levels of elements recorded as compared to the threshold levels recommended in the literature for medicinal plants require extraordinary precautionary measures before or during using Artemisia as medication to avoid metal toxicity.


Asunto(s)
Artemisia , Oligoelementos , Espectrofotometría Atómica/métodos , Pakistán , Cobre/análisis , Zinc/análisis , Sodio/análisis , Oligoelementos/análisis
10.
Talanta ; 253: 123898, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36108519

RESUMEN

A method based on flow injection hydride generation atomic absorption spectrometry (FI-HGAAS) with an on-line pre-reduction of Se(VI) to Se(IV) was developed and optimized to determine phosphate-extractable Se (0.1 M phosphate buffer KH2PO4/K2HPO4 at pH 7). The extracted fraction involves water-soluble Se (i.e. the most mobile Se fraction) and exchangeable Se (i.e. sorbed onto soil component surface). Kinetic discrimination mechanisms allowed the complete removal of interferences caused by organic matter due to the formation of humic substances (HS)-Se(IV) complexes observed when batch pre-reduction processes were used. Se(IV) and Se(VI) recoveries ranged 95-105% at a fortification level of 150 µg kg-1. The pre-reduction was efficiently carried out in 20 s in a 6 M HCl medium at 100 °C. Results from phosphate-extractable fractions were comparable to those obtained by ICP-MS. Se bound to organic matter was released digesting the remaining material from the phosphate buffer extraction with 0.1 M K2S2O8. Detection and quantification limits were 15 µg kg-1 Se and 50 µg kg-1 Se, respectively, in each fraction. The methodology was applied to 10 agricultural soils from Argentina with total Se concentration levels between 130 µg kg-1 and 419 µg kg-1.


Asunto(s)
Selenio , Espectrofotometría Atómica , Suelo , Fosfatos
11.
Crit Rev Anal Chem ; 53(2): 339-359, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34328385

RESUMEN

For thousands of years, medicinal plants (MPs) have been one of the main sources of drugs worldwide. However, recently, heavy metal pollution has seriously affected the quality and safety of MPs. Consuming MPs polluted by heavy metals such as Pb, Hg, and Cu significantly threaten the health of consumers. To manage this situation, the levels of heavy metals in MPs must be controlled. In recent years, this field has attracted significant attention, but few researchers have systematically summarized various analytical methods. Therefore, it is necessary to investigate methods that can accurately and effectively detect the amount of heavy metals in MPs. Herein, some important analytical methods used to detect heavy metals in MPs and their applications have been introduced and summarized in detail. These include atomic absorption spectrometry, atomic fluorescence spectrometry, inductively coupled plasma mass spectrometry, inductively coupled plasma atomic emission spectrometry, X-ray fluorescence spectrometry, neutron activation analysis, and anodic stripping voltammetry. The characteristics of these methods were subsequently compared and analyzed. In addition, high-performance liquid chromatography, ultraviolet spectrophotometry, and disposable electrochemical sensors have also been used for heavy metal detection in MPs. To elucidate the systematic and comprehensive information, these methods have also been briefly introduced in this review.


Asunto(s)
Metales Pesados , Plantas Medicinales , Plantas Medicinales/química , Metales Pesados/análisis , Espectrofotometría Atómica/métodos , Espectrometría de Fluorescencia
12.
Talanta ; 252: 123897, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36067699

RESUMEN

This work proposes an automated strategy for the inorganic selenium speciation in infusion tea samples, employing an MSFIA-CVG-AFS system and sodium tetrahydroborate for chemical vapor generation. The selenium total is determined after an online prereduction step of selenium (VI) to selenium (IV) in alkaline media, using a UV reactor with a 15 W Hg lamp. Selenium (IV) is quantified directly on the sample, and selenium (VI) is determined by the difference between the total selenium and selenium (IV) concentrations. The optimization of the chemical parameters: hydrochloric acid - hydrobromide acid solution concentration, potassium iodide concentration, sodium hydroxide concentration, and sodium tetrahydroborate concentration was performed using a (24-1) two-level fractional factorial design. The validation parameters were determined for total selenium and selenium (IV), and the results found were: limits of detection and quantification of 0.05 and 0.18 µg L-1, respectively; a linear range of 0.18-5.0 µg L-1, precision expressed as the relative standard deviation of 2.1% for a sample number of 10, for both analytes. The system allows the speciation analysis with an injection throughput of 15 injections per hour. This analytical method was applied for inorganic selenium speciation in nine infusions of tea samples purchased commercially in supermarkets in Palma de Mallorca City, Spain. The concentrations of selenium (IV) and total selenium varied from 0.2 to 0.6 µg L-1 and 0.4-2.0 µg L-1, respectively. The accuracy method was evaluated using spike tests, and the recoveries achieved varied from 91 to 111%.


Asunto(s)
Selenio , Selenio/análisis , Espectrometría de Fluorescencia , Borohidruros , , Espectrofotometría Atómica/métodos
13.
Anal Methods ; 15(1): 56-62, 2022 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-36477290

RESUMEN

In this study, an analytical strategy was proposed for the determination of cobalt at trace levels by using a flame atomic absorption spectrophotometry (FAAS) system after magnetic hydrogel based dispersive solid phase extraction (MH-DSPE). Poly(vinyl alcohol) based magnetic hydrogels (PVA-MH) were synthesized easily, quickly, and cost effectively in the laboratory and used as an adsorbent material in the microextraction process. Under the optimum experimental conditions, the limit of detection (LOD) and limit of quantitation (LOQ) values were recorded as 4.2 and 14.1 µg L-1, respectively. To investigate the matrix effects on the analyte signal, spike experiments were performed using chamomile tea extracts and good recovery results were obtained between 85.7 and 113.8%. A 57.8-fold improvement was achieved in the detection power compared to that of a conventional FAAS system. The results obtained throughout all experimental studies demonstrated the applicability in addition to the accuracy of the method for the quantification of trace levels of cobalt with high accuracy in a chamomile tea matrix.


Asunto(s)
Cobalto , Microextracción en Fase Líquida , Espectrofotometría Atómica/métodos , Cobalto/análisis , Manzanilla , Alcohol Polivinílico , Microextracción en Fase Líquida/métodos , Cuarzo , Extracción en Fase Sólida , , Fenómenos Magnéticos
14.
Molecules ; 27(23)2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36500243

RESUMEN

Calcium (Ca) is a macronutrient necessary for the proper functioning of an organism. In the case of insufficient consumption with diet, its deficiencies can be supplemented with food supplements (FS). These supplements are used, for example, as an auxiliary in the prevention of osteoporosis, allergies, hair loss or nail brittleness. The purpose of the study was to assess the compliance of Ca content with the manufacturers' declaration. The material consisted of 108 FS. Ca content was determined by atomic absorption spectrometry (AAS). It was shown that 1.9% of the samples were characterized by a Ca content that was too low in comparison to the manufacturer's declaration, while a content that was relatively too high was found in 54.6% of FS. The quality of FS should be monitored to ensure patient safety.


Asunto(s)
Calcio , Osteoporosis , Humanos , Calcio/análisis , Suplementos Dietéticos/análisis , Espectrofotometría Atómica , Dieta
15.
Int J Mol Sci ; 23(22)2022 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-36430428

RESUMEN

Cyanobacteria are characterized by high iron content. In this research, we collected ten commercial samples of Arthrospira spp. sold as food supplement to determine iron content and assess whether iron speciation showed variability among samples and changed respect to A. platensis grown in controlled conditions. Particular attention was also paid to phycocyanin, as an iron-binding protein. In six of the ten samples, 14 essential and non-essential trace elements were analysed using ICP-MS. Iron content measured in samples using atomic absorption spectrometry (AAS) varied from 353 (sample S5) to 1459 (sample S7) µg g-1 dry weight and was in the range of those reported by other authors in commercial supplements. Iron speciation was studied using size exclusion chromatography followed by the analysis of the collected fraction for the determination of iron by AAS and for protein separation using SDS-PAGE. Overlapping chromatographic profiles were obtained for total proteins, phycocyanin and iron, although quantitative differences were evidenced among the samples analysed. In most samples, iron was mainly bound to ligands with high molecular mass; however, in four samples iron was also bound to ligands with low molecular mass. In fractions containing the most relevant iron burden, the principal protein was phycocyanin, confirming its role as an iron-binding protein in commercial samples.


Asunto(s)
Ficocianina , Spirulina , Ficocianina/metabolismo , Spirulina/metabolismo , Hierro/metabolismo , Espectrofotometría Atómica , Transferrina/metabolismo
16.
J Trace Elem Med Biol ; 73: 127038, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35863260

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a systemic disease affecting multiple organs. Furthermore, viral infection depletes several trace elements and promotes complex biochemical reactions in the body. Smoking has been linked to the incidence of COVID-19 and associated mortality, and it may impact clinical effects, viral and bacterial conversion, and treatment outcomes. OBJECTIVES: To study the relationship between severe acute respiratory syndrome coronavirus type 2 and the elemental concentrations of selenium (Se) and mercury (Hg) in biological samples from smokers and nonsmokers infected with the virus and in healthy individuals. METHOD: We evaluated changes in the concentrations of essential (Se) and toxic (Hg) elements in biological samples (blood, nasal fluid, saliva, sputum, serum, and scalp hair) collected from male smokers and nonsmokers (aged 29-59 years) infected with COVID-19 and from healthy men in the same age group. The patients lived in different cities in Sindh Province, Pakistan. The Se and Hg concentrations were determined using atomic absorption spectrophotometry. RESULTS: Se concentrations in all types of biological samples from smokers and nonsmokers with COVID-19 were lower than those of healthy smokers and nonsmokers. Hg concentrations were elevated in both smokers and nonsmokers with COVID-19. CONCLUSIONS: In the current study, persons infected with COVID-19 had higher concentrations of toxic Hg, which could cause physiological disorders, and low concentrations of essential Se, which can also cause weakness. COVID-19 infection showed positive correlations with levels of mercury and selenium. Thus, additional clinical and experimental investigations are essential.


Asunto(s)
COVID-19 , Mercurio , Selenio , Cabello/metabolismo , Humanos , Masculino , Espectrofotometría Atómica
17.
Anal Chim Acta ; 1202: 339637, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35341530

RESUMEN

A direct solid sampling method based on high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GFAAS) for the determination of selenium (Se) in biological tissues was optimized. The main analytical line of Se at 196.0267 nm was used to carry out all HR-CS AAS measurements. Different chemical modifiers were evaluated to prevent the loss of Se during the application of the GFAAS temperature program and avoid the interferences due to the presence of phosphorus compounds in sample matrix. The best results were achieved using ruthenium coated platforms and a palladium nanoparticle suspension (Pd NP) as co-injected modifier. Calibration was performed using aqueous standard solutions of Se(IV). For solid sampling, the optimal range of sample mass was between 0.2 and 0.8 mg. The limit of detection (LOD) was 0.06 ng (0.075 µg g-1 using a sample mass of 0.8 mg). The developed solid sampling HR-CS GFAAS method was used for Se determination in two certified reference materials of dogfish tissues and lyophilized and powdered real samples of fish tissues and chicken liver. The precision obtained in these analyses, expressed as relative standard deviation (RSD), was between 5.5 and 8.6% (n = 6). For validation purposes, the results obtained by the solid sampling HR-CS GFAAS method were compared with those found performing the analysis by HR-CS hydride generation AAS (HR-CS HGAAS) after microwave acid digestion of the samples. The Se concentrations obtained for both methods agreed at a 95% confidence level (Student's t-test), indicating the suitability of the proposed solid sampling HR-CS GFAAS method to determine Se in biological samples.


Asunto(s)
Grafito , Selenio , Grafito/química , Humanos , Límite de Detección , Espectrofotometría Atómica/métodos , Temperatura
18.
Clin Chim Acta ; 529: 96-103, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35183529

RESUMEN

BACKGROUND: The influence of essential nutrients such as calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), selenium (Se), and zinc (Zn) on male fertility has been extensively studied. For reproductive health, adequate spermatogenesis, sperm maturation and motility, as well as optimal sperm function, these essential elements are required. Several pathologic and male infertility disorders have been linked to an imbalance of these elements. METHODS: The purpose of this study was to determine the relationship between essential and toxic elements, such as Ca, Cu, Fe, Mg Se, and Zn, as well as cadmium (Cd), lead (Pb), and mercury (Hg) in human biological samples, such as blood, serum, and seminal plasma, from 96 referent male adults aged 21 to 49 years, who were further divided into three age groups. The biological samples of Eunuch people (n = 37), ranging in age from 21 to 42 years, were also analysed for comparison. The method of acid digestion was controlled by a microwave oven. The essential and toxic elements in the oxidised biological samples were determined using atomic absorption spectrometry. Certified reference material of blood and serum was being used to validate the methodology's accuracy. RESULT: The Ca, Cu, Fe, Mg, Se, and Zn concentrations in blood and serum samples of Eunuch people were found to be lower, whereas Cd, Pb, and Hg levels were significantly higher than those found in data from normal adult male subjects (p 0.001). The results reveal that the concentrations of Ca, Cu, Fe, Mg, Se, and Zn in the seminal plasma of adult male participants in the younger age group (21-29) were higher than those in the older age groups (30-39) and (40-49). Although essential trace element levels in Eunuch people's biological samples were significantly lower than those observed in adult male subjects. CONCLUSION: Essential elemental deficiency and elevated levels of toxic heavy metals in all biological fluid samples may have significant negative effects on human reproductive health (sperm quality and function), leading to male infertility.


Asunto(s)
Selenio , Oligoelementos , Adulto , Anciano , Cobre , Humanos , Masculino , Persona de Mediana Edad , Espectrofotometría Atómica , Adulto Joven , Zinc/análisis
19.
Medicine (Baltimore) ; 101(1): e28538, 2022 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-35029924

RESUMEN

ABSTRACT: Calcium (Ca) and magnesium (Mg), which play an important role in several cellular processes, is essential for normal development of the skeleton and maintenance of tissue homeostasis. Deficiency of these elements might delay bone fracture recovery or accelerates bone loss. We aimed to examine whether supplementation of trace element (TE) promotes fracture healing in accidentally fracturing adults by involvement of inflammatory mechanism.A short-term follow-up in clinic was performed. Totally, 117 subjects diagnosed with multiple fractures by traffic accidents were recruited in this study. Serum Ca and Mg levels were measured by inductively coupled plasma atomic emission spectrophotometry. Short-term changes such as serum C-reactive protein, interleukin (IL)-1ß, IL-6, and tumor necrosis factor alpha in normal treatment and TE supplement groups were detected by enzyme-linked immunosorbent assay. Student t test and the Spearman correlation were performed to analyze the data.Significantly negative correlations between Ca (r = 0.7032; P < .001) and Mg (r = 0.2719; P < .05) and injury severity score were observed. Serum Ca and Mg were significantly increased at Day 5, 7, and 9 following TE supplements. After treatment, serum C-reactive protein, IL-1ß, IL-6, and tumor necrosis factor alpha were significantly reduced whereas cytokine levels of the TE supplement group were found to be lower than that of the normal treatment group after Day 3.These findings suggest that Ca and Mg levels are associated with the injury severity of multiple fractures, and the supplement could reduce the inflammation, which may be beneficial for the bone recovery and disease process.


Asunto(s)
Calcio/sangre , Citocinas/sangre , Fracturas Óseas , Fracturas Múltiples , Magnesio/sangre , Accidentes de Tránsito , Adulto , Proteína C-Reactiva/análisis , Calcio/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Puntaje de Gravedad del Traumatismo , Interleucina-6/sangre , Magnesio/administración & dosificación , Masculino , Persona de Mediana Edad , Espectrofotometría Atómica , Factor de Necrosis Tumoral alfa/sangre
20.
Food Chem ; 377: 132057, 2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35030340

RESUMEN

This work reports the development of a simple, sensitive and low-cost analytical method for the trace determination of copper. A metal sieve-linked double syringe liquid phase microextraction method was used to preconcentrate copper into measurable quantities for FAAS system. The pressurized mixing offered by the automated syringe system and the sieve connector enhanced surface area for analyte and extraction solvent interaction, this significantly increased the extraction efficiency for copper. There was therefore no need for auxiliary organic solvents as disperser solvents for the extractant dichloromethane. The limits of detection and quantification, linear dynamic range and percent relative standard deviation values calculated for copper under optimum conditions of the method were 1.5 and 5.1 µg L-1, 5.0-500 µg L-1 and 8.4%, respectively. The developed method was successfully employed to determine copper (0.75-8.06 mg kg-1) in unspiked olive leaf samples.


Asunto(s)
Cobre , Olea , Extractos Vegetales/química , Cobre/análisis , Límite de Detección , Microextracción en Fase Líquida/métodos , Olea/química , Solventes , Espectrofotometría Atómica
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