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1.
《Analytical letters》2012,45(5):932-941
The heavy metal content was investigated for six mushroom species native to Jordan. Metal (Cu, Pb, Cd, Fe, Zn, Mn, Ni, and Co) content in soil substrate and their relation to metal concentrations in mushroom and underlying soil were determined by flame and graphite furnace atomic absorption spectrometry. Mushroom species and soil were collected from different places in Jordan. The highest Cu level was 51.84 µg g?1 for the species Lepista nuda; whereas, the lowest Cu level was found to be 18.51 µg g?1 in Calvatia utriformis. Among the wild mushrooms, the highest Pb level was found as 4.81 µg g?1 in Bovista plumbea, whereas the lowest Pb concentration was 2.01 µg g?1 in Calvatia utriformis. The highest Cd level was determined as 1.9 µg g?1 for Lepista nuda, whereas the lowest Cd level was 0.58 µg g?1 for the species of Polyporus frondosus. The highest Zn level was 58.77 µg g?1 for the species of Lepista nuda and the lowest Zn concentration was found 35.98 µg g?1 in Calvatia utriformis. The highest Fe level was found as 317 µg g?1 in Lepista nuda, whereas the lowest Fe concentration was 211.7 µg g?1 in Calvatia utriformis. The highest Mn content was 36.55 µg g?1 for Russula delica, whereas the lowest Mn level was 24.5 µg g?1 for the species Bovista plumbea. The highest Ni content was found as 12.65 µg g?1 for Russula delica, whereas the lowest Ni level was 0.17 µg g?1 for Bovista plumbea. The highest Co content in the tested mushrooms was found as 3.5 µg g?1 for the species of Agaricus bisporus, whereas the lowest Co level was 0.85 µg g?1 for Polyporus frondosus. The results indicated that, in general, heavy metal contents in all mushroom species were lower than the underlying soil substrates except for some mushroom species.  相似文献   

2.
《Analytical letters》2012,45(1):48-59
Parthenium hysterophorus L., is an obnoxious weed known for its environmental health hazards and medicinal uses. These characteristics are due to presence of sesquiterpene lactones and organic acids; therefore a rapid and sensitive analytical procedure using HPLC-PDA-MS-MS was developed and optimized for separation, identification, and quantification of parthenin and six organic acids. Separation and characterization of compounds was achieved on a RP-C18 column with 1% acetic acid in water (A) and acetonitrile (B) as a mobile phase at a flow rate of 0.6 mL min?1 and by matching their UV and mass spectra with reference compounds. Six organic acids (ferulic acid, 0.1 mg g?1 to coumaric acid, 13.6 mg g?1) and parthenin (27.4 mg g?1) were characterized within 26 minutes of chromatographic separation in plant extract. The calibration curves are linear with correlation coefficients from 0.985 to 0.998, limit of detection and quantification ranged between 1.0 µg mL?1 (anisic acid) to 2.2 µg mL?1 (parthenin) and 2.5 µg mL?1 (coumaric acid) to 5.2 µ g mL?1 (parthenin) and recovery ranged between 90.9% to 97.3%. To the best of our knowledge this is the first report for the simultaneous separation of parthenin and organic acids. The method is applicable for screening of commercial crops, medicinal plants, and their products which might be mixed with P. hysterophorus during harvesting period.  相似文献   

3.
《Analytical letters》2012,45(11):1952-1964
The distributions of cadmium and lead in marine sediments, surrounding soil, stones, and atmospheric particulate matter were determined at different locations in Split, Croatia. The determination of cadmium and lead was performed by flame atomic absorption spectrometry whereas atmospheric particulate matter samples were analyzed by inductively coupled plasma–optical emission spectrometry. Cadmium concentrations in the stones and soil were between 0.2 to 0.6 µg g?1 and 0.2 to 0.9 µg g?1. The concentration in the atmospheric particulate matter were <0.2 µg m?2 d?1(detection limit) to 1.4 µg m?2 d?1. Lead concentrations in marine sediments, stones, soil, and atmospheric particulate matter ranged from 31.2 to 144.4 µg g?1, 9.3 to 29.4 µg g?1, 11.3 to 66.1 µg g?1, and 0.5 to 241.4 µg m?2 d?1, respectively. The relationship between determined parameters was established using principal component analysis and the results are in agreement with the assumption that anthropogenic sources play important roles for lead and cadmium distribution.  相似文献   

4.
An effective method utilising pressurised fluid extraction (PFE) to simultaneously extract polycyclic aromatic hydrocarbons (PAHs) and their polar oxidation products from atmospheric particulate matter (PM) is presented. The PFE method is advantageous over the traditional Soxhlet extraction due to its lower solvent consumption (9 mL compared to 90 mL) and shorter extraction time (15 min versus 18 h). Seventy compounds including PAHs and polar PAH oxidation products containing carbonyl (oxy-PAHs), hydroxyl (hydroxy-PAHs), and carboxylic acid (carboxy-PAHs) groups were targeted in the extraction of two different PM matrices: wood smoke (WS) and diesel exhaust (DE) PM. The PFE method was optimised and then compared to Soxhlet extraction for both PM matrices. The overall amounts of PAHs and their derivatives extracted from WS PM were slightly higher for the optimised PFE method (1849 ± 21 and 1863 ± 25 µg g?1 with dichloromethane (DCM) and methanol (MeOH), respectively) than those obtained with Soxhlet extraction (1726 ± 33 and 1769 ± 22 µg g?1 with DCM and MeOH, respectively). For DE PM (standard reference material (SRM) 2975) the overall amounts extracted by both methods were similar (average of 165 ± 6 µg g?1), agreeing with previously published values. The detailed evaluation of extraction efficiencies for WS PM showed similar amounts for unfunctionalised PAHs (1100 µg g?1) for both methods and solvents. For DE PM the mass yields for PAHs using PFE with DCM (62 ± 1 µg g?1) were the highest and nearly 20% higher than those obtained with MeOH (53 ± 2 µg g?1). The total mass yields of carboxy and hydroxy-PAHs from WS PM were also similar (412 ± 18 and 407 ± 11 µg g?1) for PFE and Soxhlet with MeOH, and higher than when DCM was used (371 ± 5 and 379 ± 12 µg g?1 for PFE and Soxhlet, respectively). For both matrices, the PFE yields for oxy-PAHs were higher than those obtained with Soxhlet.  相似文献   

5.
《Analytical letters》2012,45(6):1052-1062
A new simplified extraction of gold(III) using a room-temperature ionic liquid prior to determination by flame atomic absorption spectrometry has been developed. The extraction method uses 1-butyl-3-methylimidazolium hexafluorophosphate without a chelating agent. The parameters of the extraction system were investigated in detail. Under the optimized conditions, a linear range of 0.19 to 38.20 µg · mL?1, a limit of detection of 0.072 µg · mL?1, an enrichment factor of 10.0, and an extraction capacity of 6.6 mg · g?1 were obtained. The extraction mechanism and the selectivity of 1-butyl-3-methylimidazolium hexafluorophosphate for gold(III) were also investigated. The method was applied for the determination of gold(III) in water samples with satisfactory results.  相似文献   

6.
《Analytical letters》2012,45(8):1400-1408
There are three major production bases of navel oranges in China, including Southern Jiangxi Province, Southern Hunan Province, and the Three Gorges District of the Yangtze River. Southern Jiangxi and Southern Hunan are also famous for rare earth elements that are ionic, making them easily passed from soil to plants and fruits. To test the relative enrichment of rare earth elements in navel oranges from these production sites, ICP-MS analysis was performed following a microwave digestion procedure. The concentrations of La, Ce, Pr, and Nd in navel orange peels from Southern Jiangxi and Southern Hunan (1.26–1.86 µg g?1) were much higher than results from the Three Gorges (0.23–0.46 µg g?1). Moreover, yttrium is relatively enriched (0.25–0.29 µg g?1) in navel orange peels from Southern Jiangxi at concentrations almost twice that from Southern Hunan (0.15 µg g?1). The various concentrations and distribution of rare earth elements offers the possibility of traceability and authentication of navel oranges. Meanwhile, navel orange peels from Southern Jiangxi posed no risk in consumption, based on the maximum limit level (≤0.7 µg g?1, wet weight) of rare earth elements in food issued in China (GB 2762-2005).  相似文献   

7.
The aim of this study was to examine the impact of divalent copper, iron, manganese, and zinc ions on the production of erythritol from glycerol by Yarrowia lipolytica and their effect on the activity of erythrose reductase. No inhibitory effect of the examined minerals on yeast growth was observed in the study. Supplementation with MnSO4·7H2O (25 mg l?1) increased erythritol production by Y. lipolytica by 14.5 %. In the bioreactor culture with manganese ion addition, 47.1 g l?1 of erythritol was produced from 100.0 g l?1 of glycerol, which corresponded to volumetric productivity of 0.87 g l?1 h?1. The addition of Mn2+ enhanced the intracellular activity of erythrose reductase up to 24.9 U g?1 of dry weight of biomass (DW), hence, about 1.3 times more than in the control.  相似文献   

8.
《Analytical letters》2012,45(5):856-867
A novel flow injection system incorporating a micro-column packed with carbon nanotubes (CNTs) as an adsorbent has been applied to the on-line preconcentration of trace silver with detection by flame atomic absorption spectrometry. Silver is first chelated by dithizone (H2Dz), then retained on the CNTs surface and afterward quantitatively eluted by methanol. Influencing parameters, including the concentration of reaction reagent, enrichment variables, and elution variables were investigated. The adsorption mechanisms of Ag-H2Dz chelate retained onto the CNTs surface have also been studied. By loading 6.9 mL sample solution, a linear calibration graph is obtained within the range of 3–120 µg L?1 with R of 0.9996, and a detection limit (3σ) of 0.8 µg L?1 is achieved, along with a precision of 1.6% R.S.D. at the 30 µg L?1 level (n = 7). The dynamic sorption capacity of CNTs for silver is 122 mg g?1. The procedure is demonstrated by measurement of spike recovery in a series of water samples, giving rise to spike recoveries in the range of 96.8–99.7%.  相似文献   

9.
Inorganic elements are responsible for essential bodily functions, such as osmotic regulation, cardiac frequency and contractibility, blood clotting and neuromuscular excitability. The determination of inorganic elements in corporeal fluids such as blood, serum, plasma and urine is used as a monitor for a part or the whole organism; their values, then, are compared with reference interval values. In this study, the energy dispersive X-ray fluorescence spectrometry (EDXRF), applying the Fundamental Parameters method, for the determination of inorganic elements in whole blood samples from humans and laboratory animals, was used. Peripheral blood samples were collected and, before coagulation, 100 μL of sample were deposited onto Whatman No. 41 filter paper and dried, using infrared spotlight. The reference interval values for healthy Brazilian population of Na were found to be 1,788–1,826 μg g?1, of Mg 63–75 μg g?1, of P 602–676 μg g?1, of S 1,519–1,718 μg g?1, of Cl 2,743–2,867 μg g?1, of K 1,508–1,630 μg g?1, of Ca 214–228 μg g?1, of Fe 170184 μg g?1, of Cu 4–6 μg g?1 and of Zn 1–3 μg g?1. The reference interval values for golden hamster (Mesocricetus auratus) of Na were found to be 1,714–1,819 μg g?1, Mg 51–79 μg g?1, P 970–1,080 μg g?1, S 1,231–1,739 μg g?1, Cl 2,775–2,865 μg g?1, of K 1,968–2,248 μg g?1, of Ca 209–257 μg g?1, of Fe 145–267 μg g?1, of Cu 4–6 μg g?1 and of Zn 3–5 μg g?1. A comparative study between EDXRF and instrumental neutron activation analysis data was carried out and the results for both techniques are statistically equal (α = 0.05). The results contribute for the establishment of reference interval values for Na, Mg, P, S, Cl, K, Ca, Cu and Zn in the healthy Brazilian population and the referred laboratory animal species.  相似文献   

10.
《Analytical letters》2012,45(10):1842-1852
A dynamic ultrasound-assisted extraction method using Atomic Absorption and Atomic Fluorescence spectrometers as detectors was developed to analyze mercury, arsenic, and barium from herbarium mount paper originating from the herbarium collection of the National Museum of Wales. The variables influencing extraction were optimized by a multivariate approach. The optimal conditions were found to be 1% HNO3 extractant solution used at a flow rate of 1 mL min?1. The duty cycle and amplitude of the ultrasonic probe was found to be 50% in both cases with an ultrasound power of 400 W. The optimal distance between the probe and the top face of the extraction chamber was found to be 0 cm. Under these conditions the time required for complete extraction of the three analytes was 25 min. Cold vapor and hydride generation coupled to atomic fluorescence spectrometry was utilized to determine mercury and arsenic, respectively. The chemical and instrumental conditions were optimized to provide detection limits of 0.01 ng g?1 and 1.25 ng g?1 for mercury and arsenic, respectively. Barium was determined by graphite-furnace atomic absorption spectrometry, with a detection limit of 25 ng g?1. By using 0.5 g of sample, the concentrations of the target analytes varied for the different types of paper and ranged between 0.4–2.55 µg g?1 for Ba, 0.035–10.47 µg g?1 for As, and 0.0046–2.37 µg g?1 for Hg.  相似文献   

11.
《Analytical letters》2012,45(11):1921-1930
This paper describes a simple and sensitive method for the determination of manganese in human urine by graphite furnace atomic absorption spectroscopy (GFAAS), which includes sample preparation by microwave digestion. Matrix modifier combinations, the digestion power, pyrolysis, and atomization temperatures were optimized. A mixture of 5.0 µg Pd(NO3)2 and 3.2 µg Mg(NO3)2 modifier presented the best performance. The optimal temperatures for pyrolysis and atomization were 1500°C and 1950°C, respectively. The GFAAS method was compared to inductively coupled plasma–mass spectrometry (ICP–MS) for the determination of manganese in urine. Analytical figures of merit for GFAAS and ICP–MS were: accuracy (3.46%, 2.19%), precision (3.61%, 5.84%), LOD (0.109 µg · L?1, 0.015 µg · L?1), LOQ (0.327 µg · L?1, 0.045 µg · L?1), and recovery (80–100%, 74–89%). Both methods were employed for the determination of Mn in urine and the results were compared statistically.  相似文献   

12.
We present a method for the separation and determination of transition metals in electrolytes based on ion chromatography (IC) with post-column reaction (PCR) and serial conductivity and spectrophotometric detection. Three IC columns [Metrosep C4—250/4.0 (column A), Metrosep C6—250/4.0 (column B), and Nucleosil 100-5SA—250/4.6 (column C)] with different capacities, and stationary phases were used and compared with each other for method development. All spectrophotometric measurements were carried out with 4-(2-pyridylazo)resorcinol (PAR) as PCR reagent at a wavelength of 500 nm. To characterize the precision of the separation, the selectivity for the analysis of transition metals (nickel, cobalt, copper, and manganese) in the presence of large amounts of lithium and the resolution of the peaks were determined and compared with one another. Furthermore, the limits of detection (LOD) and quantification (LOQ) were determined for the transition metals. The LODs and LOQs determined by column C were as follows: cobalt (LOD/LOQ): 9.4 µg L?1/31.3 µg L?1, manganese (LOD/LOQ): 7.0 µg L?1/23.5 µg L?1, and nickel (LOD/LOQ): 6.3 µg L?1/21.1 µg L?1. Finally, the concentration of transition metal dissolution of the cathode material Li1Ni1/3Co1/3Mn1/3O2 (NCM) was investigated for different charge cut-off voltages by the developed IC method.  相似文献   

13.
The mucilage in Lepidium sativum L. is considered a biologically active compound with diverse medicinal properties. Different explants (hypocotyls and leaf) were transferred to Murashige and Skoog (MS) medium supplemented with twelve different plant growth regulator combinations under two different incubations (light and dark). The best mucilage production from callus (36.76% g g?1 dry weight) was obtained in the MS medium supplemented with 1 mg L?1 of 2, 4-D and 2 mg L?1 of BAP under the light condition. The mucilage produced by callus culture was nearly three times more than the mucilage yield of the seeds. The glucose, arabinose + mannose and galactose were 43.4 (mg g?1 DW), 195.3 (mg g?1 DW) and 86.2 (mg g?1 DW) in the mucilage originated from seed, callus leaf and callus hypocotyl, respectively. The present study proposes an efficient method for producing large scales of mucilage with a favorable sugar aimed at food or pharmaceutical industries.  相似文献   

14.
Two anthracene molecularly imprinted nanoparticle polymers namely; An–MINP1 and An–MINP2, were synthesized using the precipitation polymerization method. An–MINPs were used for selective separation of anthracene from aqueous solutions. The data revealed that the maximum binding capacity of An–MINPs for anthracene were 320.8 and 374.3 mg g?1 for An–MINP1 and An–MIPN2, respectively, compared with 2.8 and 4 µg g?1 obtained by using their corresponding non-imprinted polymers NIP1 and NIP2, respectively. Under optimized conditions, An–MINPs give high selectivity and sensitivity of anthracene separation. The anthracene uptake percentage from aqueous solutions ranged from 90.3 to 99.9%.  相似文献   

15.
《Analytical letters》2012,45(12):2095-2103
Titanium was determined in nano-titanium(IV) oxide food packaging by microwave digestion with inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). Microwave digestion was optimized using different acid combinations. Both spectrometry techniques showed good reproducibility, repeatability, and recovery. For ICP-AES, the limit of detection was 5.0 mg kg?1, the linear dynamic range was 100–5000 µ g L?1, the average recoveries for blank samples spiked with titanium were between 94.7% and 100.1%, and the relative standard deviations were from 2.1% to 7.1%. By ICP-MS, the limit of detection was 0.3 mg kg?1, the linear dynamic range was 0.5–200 µ g L?1, the recoveries were 88.4%–96.3%, and the relative standard deviations were 6.3%–7.4%. These results indicated that methods were effective for the determination of titanium in food packaging.  相似文献   

16.
《Analytical letters》2012,45(17):2747-2757
Abstract

Brazilian sugarcane spirits were analyzed to elucidate similarities and dissimilarities by principal component analysis. Nine aldehydes, six alcohols, and six metal cations were identified and quantified. Isobutanol (LD 202.9 µg L?1), butiraldehyde (0.08–0.5 µg L?1), ethanol (39–47% v/v), and copper (371–6068 µg L?1) showed marked similarities, but the concentration levels of n-butanol (1.6–7.3 µg L?1), sec-butanol (LD 89 µg L?1), formaldehyde (0.1–0.74 µg L?1), valeraldehyde (0.04–0.31 µg L?1), iron (8.6–139.1 µg L?1), and magnesium (LD 1149 µg L?1) exhibited differences from samples.  相似文献   

17.
A simple, rapid and sensitive column liquid chromatographic method was developed and validated to measure simultaneously the amount of ascorbic acid and phenolic acids at single wavelength (240 nm) in order to assess drug release profiles and drug-excipients compatibility studies for a new sustained release tablet formulation and its subsequent stability studies. A combined isocratic and linear gradient reversed-phase LC method was carried out at 240 nm. Quantification was achieved with reference to the external standards. The linearity for concentrations between 0.042 and 0.150 mg mL?1 for ascorbic acid, 0.084–0.250 mg mL?1 for chlorogenic acid, 0.053–0.360 mg mL?1 for caffeic acid, and 0.016–0.250 mg mL?1 for ferulic acid (r > 0.99 for all analytes) were established. The recovery of the active ingredients from the samples was at the range of 92.3–102.9%. Intra- and inter-day precisions were less than 2.5%. The limits of detection and quantification were 8 and 24 μg mL?1 for ascorbic acid, 18 and 54 μg mL?1 for chlorogenic acid, 37 and 112 μg mL?1 for caffeic acid, and 11 and 34 μg mL?1 for ferulic acid. The determination of the four active ingredients was not interfered by the excipients of the products. Samples were stable in the release mediums (37 °C) at least for 12 h.  相似文献   

18.
《Analytical letters》2012,45(17):2792-2807
Ultrasensitive Square Wave Anodic Stripping Voltammetry is used for the first time for the systematic determination of Cd, Pb, and Cu in siliceous spicules of marine sponges; the procedure is performed directly in hydrofluoric acid solution, according to a procedure previously established in our laboratory, with the aim of demonstrating the feasibility of such measurements and to improve knowledge of heavy metal distribution in Porifera. The following Demospongiae species are considered: Sphaerotylus antarcticus, Haliclona sp., Kirkpatrickia coulmani, and Inflatella belli from the Ross Sea, Antarctica, and Petrosia ficiformis from the Mediterranean Sea, Italy. The method shows a good accuracy; the analytical variability is approximately ±10% for all the metals studied and for all the measurements performed, showing a good repeatability of the method in consideration of low metal concentrations (order of tenths of µg g?1 dry weight, i.e., of hundreds of ng L?1 in the HF solution). In particular, the concentrations of heavy metals in the body of the sponge vary in the range 0.038–0.93 µg g?1 dry weight (d.w.) for Cd, 0.024–0.52 µg g?1 d.w. for Pb, and 0.32–1.3 µg g?1 d.w. for Cu. Similar ranges of concentration were recorded in the oscula of S. antarcticus and I. belli. Heavy metal concentration in the spicules can vary within and between specimens and, in particular, siliceous spicules of Antarctic sponges show higher concentrations of Cd and Pb and lower concentrations of Cu than those from the Mediterranean.  相似文献   

19.
The paper deals with the exploitation of Ipomoea carnea as a feedstock for the production of bioethanol. Dilute acid pretreatment under optimum conditions (3 %H2SO4, 120 °C for 45 min) produced 17.68 g L?1 sugars along with 1.02 g L?1 phenolics and 1.13 g L?1 furans. A combination of overliming and activated charcoal adsorption facilitated the removal of 91.9 % furans and 94.7 % phenolics from acid hydrolysate. The pretreated biomass was further treated with a mixture of sodium sulphite and sodium chlorite and, a maximum lignin removal of 81.6 % was achieved. The enzymatic saccharification of delignified biomass resulted in 79.4 % saccharification with a corresponding sugar yield of 753.21 mg g?1. Equal volume of enzymatic hydrolysate and acid hydrolysate were mixed and used for fermentation with a hybrid yeast strain RPRT90. Fermentation of mixed detoxified hydrolysate at 30 °C for 28 h produced ethanol with a yield of 0.461 g g?1. A comparable ethanol yield (0.414 g g?1) was achieved using a mixture of enzymatic hydrolysate and undetoxified acid hydrolysate. Thus, I. carnea biomass has been demonstrated to be a potential feedstock for bioethanol production, and the use of hybrid yeast may pave the way to produce bioethanol from this biomass.  相似文献   

20.
The objective of this study was to develop a simple, efficient and reliable method for routine quantitative analysis for Psoralea corylifolia L. An ultra performance liquid chromatography with DAD detector system was employed for simultaneous quantification of ten compounds. The chromatographic analysis was performed by UPLC with C18 column and gradient elution of 0.05% formic acid aqueous solution and acetonitrile in 16 min. All calibration curves were linear (R 2 ≥ 0.9990) over the tested ranges. The LOD and LOQ were lower to 13.07 and 39.22 ng mL?1 with 2 μL of injection volume, respectively. The intra- and inter-day precisions as determined from sample solutions were below 4.1 and 4.2%. The average recoveries were ranged from 94.2 to 108.8% with RSDs ≤ 4.6%. This validated method was applied for the analysis of ten analytes in P. corylifolia L. from different origins. The variation of the content of ten compounds was remarkable among the tested samples: psoralenoside increased from 7.42 to 17.04 mg g?1, isopsoralenoside from 6.05 to 14.34 mg g?1, psoralen from 2.37 to 3.90 mg g?1, isopsoralen from 2.53 to 3.65 mg g?1, neobavaisoflavone from 1.59 to 2.96 mg g?1, bavachin from 1.02 to 2.35 mg g?1, psoralidin from 0.45 to 1.91 mg g?1, isobavachalcone from 1.33 to 4.71 mg g?1, corylifol A from 1.02 to 2.40 mg g?1 and bakuchiol from 28.10 to 63.89 mg g?1.  相似文献   

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