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Zhang Y, Qiu G, Wang R, Guo Y, Guo F, Wu J. Preparation of Bamboo-Based Hierarchical Porous Carbon Modulated by FeCl 3 towards Efficient Copper Adsorption. Molecules 2021; 26:molecules26196014. [PMID: 34641557 PMCID: PMC8512165 DOI: 10.3390/molecules26196014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/30/2021] [Accepted: 09/30/2021] [Indexed: 11/16/2022] Open
Abstract
Using bamboo powder biochar as raw material, high-quality meso/microporous controlled hierarchical porous carbon was prepared—through the catalysis of Fe3+ ions loading, in addition to a chemical activation method—and then used to adsorb copper ions in an aqueous solution. The preparation process mainly included two steps: load-alkali leaching and chemical activation. The porosity characteristics (specific surface area and mesopore ratio) were controlled by changing the K2CO3 impregnation ratio, activation temperature, and Fe3+ ions loading during the activation process. Additionally, three FBPC samples with different pore structures and characteristics were studied for copper adsorption. The results indicate that the adsorption performance of the bamboo powder biochar FBPC material was greatly affected by the meso/micropore ratio. FBPC 2.5-900-2%, impregnated at a K2CO3: biochar ratio of 2.5 and a Fe3+: biochar mass ratio of 2%, and activated at 900 °C for 2 h in N2 atmosphere, has a very high specific surface area of 1996 m2 g−1 with a 58.1% mesoporous ratio. Moreover, it exhibits an excellent adsorption capacity of 256 mg g−1 and rapid adsorption kinetics for copper ions. The experimental results show that it is feasible to control the hierarchical pore structure of bamboo biochar-derived carbons as a high-performance adsorbent to remove copper ions from water.
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Ye W, Guo J, Li N, Qi F, Cheng K, Zheng R. Depth Profiling Investigation of Seawater Using Combined Multi-Optical Spectrometry. APPLIED SPECTROSCOPY 2020; 74:563-570. [PMID: 32031011 DOI: 10.1177/0003702820906890] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Depth profiling investigation plays an important role in studying the dynamic processes of the ocean. In this paper, a newly developed hyphenated underwater system based on multi-optical spectrometry is introduced and used to measure seawater spectra at different depths with the aid of a remotely operated vehicle (ROV). The hyphenated system consists of two independent compact deep-sea spectral instruments, a deep ocean compact autonomous Raman spectrometer and a compact underwater laser-induced breakdown spectroscopy system for sea applications (LIBSea). The former was used to take both Raman scattering and fluorescence of seawater, and the LIBS signal could be recorded with the LIBSea. The first sea trial of the developed system was taken place in the Bismarck Sea, Papua New Guinea, in June 2015. Over 4000 multi-optical spectra had been captured up to the diving depth about 1800 m at maximum. The depth profiles of some ocean parameters were extracted from the captured joint Raman-fluorescence and LIBS spectra with a depth resolution of 1 m. The concentrations of SO42- and the water temperatures were measured using Raman spectra. The fluorescence intensities from both colored dissolved organic matter (CDOM) and chlorophyll were found to be varied in the euphotic zone. With LIBS spectra, the depth profiles of metallic elements were also obtained. The normalized intensity of atomic line Ca(I) extracted from LIBS spectra raised around the depth of 1600 m, similar to the depth profile of CDOM. This phenomenon might be caused by the nonbuoyant hydrothermal plumes. It is worth mentioning that this is the first time Raman and LIBS spectroscopy have been applied simultaneously to the deep-sea in situ investigations.
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Vicente Vilas V, Millet S, Sandow M, Iglesias Pérez L, Serrano-Purroy D, Van Winckel S, Aldave de las Heras L. An Automated SeaFAST ICP-DRC-MS Method for the Determination of 90Sr in Spent Nuclear Fuel Leachates. Molecules 2020; 25:molecules25061429. [PMID: 32245155 PMCID: PMC7144365 DOI: 10.3390/molecules25061429] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 03/17/2020] [Accepted: 03/18/2020] [Indexed: 12/03/2022] Open
Abstract
To reduce uncertainties in determining the source term and evolving condition of spent nuclear fuel is fundamental to the safety assessment. ß-emitting nuclides pose a challenging task for reliable, quantitative determination because both radiometric and mass spectrometric methodologies require prior chemical purification for the removal of interfering activity and isobars, respectively. A method for the determination of 90Sr at trace levels in nuclear spent fuel leachate samples without sophisticated and time-consuming procedures has been established. The analytical approach uses a commercially available automated pre-concentration device (SeaFAST) coupled to an ICP-DRC-MS. The method shows good performances with regard to reproducibility, precision, and LOD reducing the total time of analysis for each sample to 12.5 min. The comparison between the developed method and the classical radiochemical method shows a good agreement when taking into account the associated uncertainties.
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Huber CS, Vale MGR, Dessuy MB, Svoboda M, Musil S, Dědina J. Sample preparation for arsenic speciation analysis in baby food by generation of substituted arsines with atomic absorption spectrometry detection. Talanta 2017; 175:406-412. [PMID: 28842009 DOI: 10.1016/j.talanta.2017.07.055] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 07/18/2017] [Accepted: 07/19/2017] [Indexed: 11/18/2022]
Abstract
A slurry sampling procedure for arsenic speciation analysis in baby food by arsane generation, cryogenic trapping and detection with atomic absorption spectrometry is presented. Several procedures were tested for slurry preparation, including different reagents (HNO3, HCl and tetramethylammonium hydroxide - TMAH) and their concentrations, water bath heating and ultrasound-assisted agitation. The best results for inorganic arsenic (iAs) and dimethylarsinate (DMA) were reached when using 3molL-1 HCl under heating and ultrasound-assisted agitation. The developed method was applied for the analysis of five porridge powder and six baby meal samples. The trueness of the method was checked with a certified reference material (CRM) of total arsenic (tAs), iAs and DMA in rice (ERM-BC211). Arsenic recoveries (mass balance) for all samples and CRM were performed by the determination of the tAs by inductively coupled plasma mass spectrometry (ICP-MS) after microwave-assisted digestion and its comparison against the sum of the results from the speciation analysis. The relative limits of detection were 0.44, 0.24 and 0.16µgkg-1 for iAs, methylarsonate and DMA, respectively. The concentrations of the most toxic arsenic species (iAs) in the analyzed baby food samples ranged between 4.2 and 99µgkg-1 which were below the limits of 300, 200 and 100µgkg-1 set by the Brazilian, Chinese and European legislation, respectively.
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Nicolodelli G, Senesi GS, de Oliveira Perazzoli IL, Marangoni BS, De Melo Benites V, Milori DMBP. Double pulse laser induced breakdown spectroscopy: A potential tool for the analysis of contaminants and macro/micronutrients in organic mineral fertilizers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 565:1116-1123. [PMID: 27261426 DOI: 10.1016/j.scitotenv.2016.05.153] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 05/20/2016] [Accepted: 05/20/2016] [Indexed: 06/05/2023]
Abstract
Organic fertilizers are obtained from waste of plant or animal origin. One of the advantages of organic fertilizers is that, from the composting, it recycles waste-organic of urban and agriculture origin, whose disposal would cause environmental impacts. Fast and accurate analysis of both major and minor/trace elements contained in organic mineral and inorganic fertilizers of new generation have promoted the application of modern analytical techniques. In particular, laser induced breakdown spectroscopy (LIBS) is showing to be a very promising, quick and practical technique to detect and measure contaminants and nutrients in fertilizers. Although, this technique presents some limitations, such as a low sensitivity, if compared to other spectroscopic techniques, the use of double pulse (DP) LIBS is an alternative to the conventional LIBS in single pulse (SP). The macronutrients (Ca, Mg, K, P), micronutrients (Cu, Fe, Na, Mn, Zn) and contaminant (Cr) in fertilizer using LIBS in SP and DP configurations were evaluated. A comparative study for both configurations was performed using optimized key parameters for improving LIBS performance. The limit of detection (LOD) values obtained by DP LIBS increased up to seven times as compared to SP LIBS. In general, the marked improvement obtained when using DP system in the simultaneous LIBS quantitative determination for fertilizers analysis could be ascribed to the larger ablated mass of the sample. The results presented in this study show the promising potential of the DP LIBS technique for a qualitative analysis in fertilizers, without requiring sample preparation with chemical reagents.
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Ozbek N, Akman S. Determination of Chlorine in Milk via Molecular Absorption of SrCl Using High-Resolution Continuum Source Graphite Furnace Atomic Absorption Spectrometry. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:5767-5772. [PMID: 27345208 DOI: 10.1021/acs.jafc.6b02024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Total chlorine in milk was determined via the molecular absorption of diatomic strontium monochloride at 635.862 nm using high-resolution continuum source graphite furnace atomic absorption spectrometry. The effects of coating the graphite furnace, using different modifiers, amount of molecule-forming element, and different calibrants were investigated and optimized. Chlorine concentrations in milk samples were determined in a Zr-coated graphite furnace using 25 μg of Sr as the molecule-forming reagent and applying a pyrolysis temperature of 600 °C and a molecule-forming temperature of 2300 °C. Linearity was maintained up to 500 μg mL(-1) of Cl. The method was tested by analyzing a certified reference wastewater. The results were in the uncertainty limits of the certified value. The limit of detection of the method was 1.76 μg mL(-1). The chlorine concentrations in various cow milk samples taken from the market were found in the range of 588-1472 mg L(-1).
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Malenfant DJ, Gillies DJ, Rehse SJ. Bacterial Suspensions Deposited on Microbiological Filter Material for Rapid Laser-Induced Breakdown Spectroscopy Identification. APPLIED SPECTROSCOPY 2016; 70:485-493. [PMID: 26819441 DOI: 10.1177/0003702815626673] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 07/17/2015] [Indexed: 06/05/2023]
Abstract
Four species of bacteria, E. coli, S. epidermidis, M. smegmatis, and P. aeruginosa, were harvested from agar nutrient medium growth plates and suspended in water to create liquid specimens for the testing of a new mounting protocol. Aliquots of 30 µL were deposited on standard nitrocellulose filter paper with a mean 0.45 µm pore size to create highly flat and uniform bacterial pads. The introduction of a laser-based lens-to-sample distance measuring device and a pair of matched off-axis parabolic reflectors for light collection improved both spectral reproducibility and the signal-to-noise ratio of optical emission spectra acquired from the bacterial pads by laser-induced breakdown spectroscopy. A discriminant function analysis and a partial least squares-discriminant analysis both showed improved sensitivity and specificity compared to previous mounting techniques. The behavior of the spectra as a function of suspension concentration and filter coverage was investigated, as was the effect on chemometric cell classification of sterilization via autoclaving.
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Gamble GR, Park B, Yoon SC, Lawrence KC. Effect of Sample Preparation on the Discrimination of Bacterial Isolates Cultured in Liquid Nutrient Media Using Laser-Induced Breakdown Spectroscopy (LIBS). APPLIED SPECTROSCOPY 2016; 70:494-504. [PMID: 26819442 DOI: 10.1177/0003702815626679] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 07/21/2015] [Indexed: 06/05/2023]
Abstract
Laser-induced breakdown spectroscopy (LIBS) is used as the basis for discrimination between two genera of gram-negative bacteria and two genera of gram-positive bacteria representing pathogenic threats commonly found in poultry processing rinse waters. Because LIBS-based discrimination relies primarily upon the relative proportions of inorganic cell components including Na, K, Mg, and Ca, this study aims to determine the effects of trace mineral content and pH found in the water source used to isolate the bacteria upon the reliability of the resulting discriminant analysis. All four genera were cultured using tryptic soy agar (TSA) as the nutrient medium, and were grown under identical environmental conditions. The only variable introduced is the source water used to isolate the cultured bacteria. Cultures of each bacterium were produced using deionized (DI) water under two atmosphere conditions, reverse osmosis (RO) water, tap water, phosphate buffered saline (PBS) water, and TRIS buffered water. After 3 days of culture growth, the bacteria were centrifuged and washed three times in the same water source. Bacteria were then freeze dried, mixed with microcrystalline cellulose, and a pellet was made for LIBS analysis. Principal component analysis (PCA) was used to extract related variations in LIBS spectral data among the four bacteria genera and six water types used to isolate the bacteria, and Mahalanobis discriminant analysis (MDA) was used for classification. Results indicate not only that the four genera can be discriminated from each other in each water type, but that each genus can be discriminated by water type used for isolation. It is concluded that in order for LIBS to be a reliable and repeatable method for discrimination of bacteria grown in liquid nutrient media, care must be taken to insure that the water source used in purification of the culture be precisely controlled regarding pH, ionic strength, and proportionate amounts of mineral cations present.
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Giakisikli G, Anthemidis AN. An automatic stirring-assisted liquid-liquid microextraction system based on lab-in-syringe platform for on-line atomic spectrometric determination of trace metals. Talanta 2016; 166:364-368. [PMID: 28213247 DOI: 10.1016/j.talanta.2016.02.057] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 02/19/2016] [Accepted: 02/24/2016] [Indexed: 11/17/2022]
Abstract
A novel simple fully automatic on-line magnetic stirring-assisted liquid-liquid microextraction method, based on the lab-in-syringe (LIS) concept, has been developed as an alternative approach for sample pretreatment and atomic spectrometric assays. The analytical process includes the in-syringe reaction of the metal ion with the chelating reagent, the analyte micro-extraction and the subsequent transportation of the extractant to the detection system for electrothermal atomic absorption spectrometric (ETAAS) quantification. This novel platform has been demonstrated for trace silver determination in various types of water samples. The method is linear from 19 to 450ngL-1 using a small volume of extraction solvent of 120μL. The entire procedure is accomplished within 240s resulting in a sampling frequency of 15h-1. The enhancement factor is 80, while the detection limit and the precision are 5.7ngL-1 and 3.3%, respectively. The developed method was evaluated by analyzing standard reference materials and spiked water samples with satisfactory recoveries.
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Kazi TG, Afridi HI, Shah F, Arain SS, Arain SA, Panhwar AH, Arain MS, Samoon MK. Development of new portable miniaturize solid phase microextraction of silver-APDC complex using micropipette tip in-syringe system couple with electrothermal atomic absorption spectrometry. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2016; 154:157-163. [PMID: 26520476 DOI: 10.1016/j.saa.2015.10.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 10/07/2015] [Accepted: 10/22/2015] [Indexed: 06/05/2023]
Abstract
An innovative and simple miniaturized solid phase microextraction (M-SPME) method, was developed for preconcentration and determination of silver(I) in the fresh and waste water samples. For M-SPME, a micropipette tip packed with activated carbon cloth (ACC) as sorbent, in a syringe system. The size, morphology and elemental composition of ACC before and after adsorption of analyte have been characterized by scanning electron microscopy and energy dispersive spectroscopy. The sample solution treated with a complexing reagent, ammonium pyrrolidine dithiocarbamate (APDC), was drawn into the syringe filled with ACC and dispensed manually for 2 to 10 aspirating/dispensing cycle. Then the Ag- complex sorbed on the ACC in micropipette was quantitatively eluted by drawing and dispensing of different concentrations of acids for 2 to 5 aspirating/dispensing cycles. The extracted Ag ions with modifier were injected directly into the electrothermal atomic absorption spectrometry for analysis. The influence of different variables on the extraction efficiency, including the concentration of ligand, pH, sample volume, eluent type, concentration and volume was investigated. Validity and accuracy of the developed method was checked by the standard addition method. Reliability of the proposed methodology was checked by the relative standard deviation (%RSD), which was found to be <5%. Under the optimized experimental variables, the limits of detection (LOD) and enhancement factors (EF), were obtained to be 0.86 ng L(-1) and 120, respectively. The proposed method was successfully applied for the determination of trace levels of silver ions in fresh and waste water samples.
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Llorente Ballesteros MT, Navarro Serrano I, López Colón JL. [Validation of an in-house method for the determination of zinc in serum: Meeting the requirements of ISO 17025]. REVISTA DE CALIDAD ASISTENCIAL : ORGANO DE LA SOCIEDAD ESPANOLA DE CALIDAD ASISTENCIAL 2015; 30:319-326. [PMID: 26546168 DOI: 10.1016/j.cali.2015.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 08/02/2015] [Accepted: 08/04/2015] [Indexed: 06/05/2023]
Abstract
OBJECTIVE The aim of this report is to propose a scheme for validation of an analytical technique according to ISO 17025. MATERIAL AND METHODS According to ISO 17025, the fundamental parameters tested were: selectivity, calibration model, precision, accuracy, uncertainty of measurement, and analytical interference. RESULTS A protocol has been developed that has been applied successfully to quantify zinc in serum by atomic absorption spectrometry. CONCLUSION It is demonstrated that our method is selective, linear, accurate, and precise, making it suitable for use in routine diagnostics.
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Huynh D, Zhou SJ, Gibson R, Palmer L, Muhlhausler B. Validation of an optimized method for the determination of iodine in human breast milk by inductively coupled plasma mass spectrometry (ICPMS) after tetramethylammonium hydroxide extraction. J Trace Elem Med Biol 2015; 29:75-82. [PMID: 25153367 DOI: 10.1016/j.jtemb.2014.07.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 07/17/2014] [Accepted: 07/18/2014] [Indexed: 10/25/2022]
Abstract
In this study a novel method to determine iodine concentrations in human breast milk was developed and validated. The iodine was analyzed by inductively coupled plasma mass spectrometry (ICPMS) following tetramethylammonium hydroxide (TMAH) extraction at 90°C in disposable polypropylene tubes. While similar approaches have been used previously, this method adopted a shorter extraction time (1h vs. 3h) and used antimony (Sb) as the internal standard, which exhibited greater stability in breast milk and milk powder matrices compared to tellurium (Te). Method validation included: defining iodine linearity up to 200μgL(-1); confirming recovery of iodine from NIST 1549 milk powder. A recovery of 94-98% was also achieved for the NIST 1549 milk powder and human breast milk samples spiked with sodium iodide and thyroxine (T4) solutions. The method quantitation limit (MQL) for human breast milk was 1.6μgL(-1). The intra-assay and inter-assay coefficient of variation for the breast milk samples and NIST powder were <1% and <3.5%, respectively. NIST 1549 milk powder, human breast milk samples and calibration standards spiked with the internal standard were all stable for at least 2.5 months after extraction. The results of the validation process confirmed that this newly developed method provides greater accuracy and precision in the assessment of iodine concentrations in human breast milk than previous methods and therefore offers a more reliable approach for assessing iodine concentrations in human breast milk.
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Ivanenko NB, Ivanenko AA, Solov'ev ND, Navolotskiĭ DV, Pavlova OV, Ganeev AA. [Determination of Al, Be, Cd, Co, Cr, Mn, Ni, Pb, Se and Tl in whole blood by atomic absorption spectrometry without preliminary sample digestion]. BIOMEDITSINSKAIA KHIMIIA 2014; 60:378-388. [PMID: 25019401 DOI: 10.18097/pbmc20146003378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Methods of whole blood trace element determination by Graphite furnace atomic absorption spectrometry (in the variant of Zeeman's modulation polarization spectrometry) have been proposed. They do not require preliminary sample digestion. Furnace programs, modifiers and blood dilution factors were optimized. Seronorm™ human whole blood reference materials were used for validation. Dynamic ranges (for undiluted blood samples) were: Al 8 ¸ 210 мg/L; Be 0.3 ¸ 50 мg/L; Cd 0.2 ¸ 75 мg/L; Сo 5 ¸ 350 мg/L; Cr 10 ¸ 100 мg/L; Mn 6 ¸ 250 мg/L; Ni 10 ¸ 350 мg/L; Pb 3 ¸ 240 мg/L; Se 10 ¸ 500 мg/L; Tl 2 ¸ 600 мg/L. Precision (RSD) for the middle of dynamic range ranged from 5% for Mn to 11 for Se.
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Khambe D, Eversole SL, Mills T, Faller RV. Protective effects of SnF2 - Part II. Deposition and retention on pellicle-coated enamel. Int Dent J 2014; 64 Suppl 1:11-15. [PMID: 24571699 PMCID: PMC9376518 DOI: 10.1111/idj.12097] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/29/2023] Open
Abstract
UNLABELLED Deposition of an acid-resistant barrier onto enamel represents a potentially superior means for delivering protection against dietary, erosive acid challenges. PURPOSE The purpose of this study was to demonstrate the ability of a stabilised stannous fluoride (SnF2 ) dentifrice to: (1) deposit a SnF2 barrier layer onto pellicle-coated enamel surfaces; (2) increase the intensity of the barrier layer over time; and (3) be retained on the enamel surface for hours after product use. METHODS Squares of human enamel were exposed to pooled saliva for 1 hour (pellicle formation) and separated into six sets. Set 1 was treated with the supernatant of a 1:3 slurry of the test dentifrice (Crest(®) Pro-Health(®) : water for 2 minutes), then rinsed. Set 2 was treated in the same manner and then placed into saliva (6 hours). Set 3 was cycled through seven repeated treatments. Set 4 was treated for seven cycles and then placed into saliva (6 hours). Set 5 was a water control, and set 6 was a water control that remained in saliva for 6 hours. Surface analysis of specimens was done using laser ablation Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). RESULTS Deposition of a barrier layer was demonstrated, beginning with the initial treatment, with Sn (using isotopes (117) Sn + (120) Sn) measured on the enamel surface as the reference marker. Deposition of the barrier layer was greater after seven cycles, and the retention of this layer was highly significant (P = 0.05, anova: 6 hours). CONCLUSIONS This study confirms that: (1) the stabilised SnF2 dentifrice deposits a barrier layer onto the enamel surface, beginning with the first use of the product; (2) this barrier is enhanced following multiple treatments; and (3) the barrier layer is retained on the enamel surface for hours after product use.
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Metzinger A, Kovács-Széles E, Almási I, Galbács G. An assessment of the potential of laser-induced breakdown spectroscopy (LIBS) for the analysis of cesium in liquid samples of biological origin. APPLIED SPECTROSCOPY 2014; 68:789-793. [PMID: 25014845 DOI: 10.1366/13-07297] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The present study describes the development of an analytical method for the determination of cesium in biological fluid samples (human urine and blood samples) by laser-induced breakdown spectroscopy (LIBS). The developed method is based on sample presentation by liquid-to-solid conversion, enhancing the emission signal by drying the liquid into small "pockets" created in a metal support (zinc plate), and allows the analysis to be carried out on as little as 1 μL of sample volume, in a closed sample cell. Absolute detection limits on the Cs I 852.1 nm spectral line were calculated by the IUPAC 3σ method to be 6 ng in the urine sample and 27 ng in the blood serum sample. It is estimated that LIBS may be used to detect highly elevated concentration levels of Cs in fluid samples taken from people potentially exposed to surges of Cs from non-natural sources.
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House E, Polwart A, Darbre P, Barr L, Metaxas G, Exley C. The aluminium content of breast tissue taken from women with breast cancer. J Trace Elem Med Biol 2013; 27:257-66. [PMID: 23870171 DOI: 10.1016/j.jtemb.2013.05.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 05/09/2013] [Accepted: 05/14/2013] [Indexed: 01/22/2023]
Abstract
The aetiology of breast cancer is multifactorial. While there are known genetic predispositions to the disease it is probable that environmental factors are also involved. Recent research has demonstrated a regionally specific distribution of aluminium in breast tissue mastectomies while other work has suggested mechanisms whereby breast tissue aluminium might contribute towards the aetiology of breast cancer. We have looked to develop microwave digestion combined with a new form of graphite furnace atomic absorption spectrometry as a precise, accurate and reproducible method for the measurement of aluminium in breast tissue biopsies. We have used this method to test the thesis that there is a regional distribution of aluminium across the breast in women with breast cancer. Microwave digestion of whole breast tissue samples resulted in clear homogenous digests perfectly suitable for the determination of aluminium by graphite furnace atomic absorption spectrometry. The instrument detection limit for the method was 0.48 μg/L. Method blanks were used to estimate background levels of contamination of 14.80 μg/L. The mean concentration of aluminium across all tissues was 0.39 μg Al/g tissue dry wt. There were no statistically significant regionally specific differences in the content of aluminium. We have developed a robust method for the precise and accurate measurement of aluminium in human breast tissue. There are very few such data currently available in the scientific literature and they will add substantially to our understanding of any putative role of aluminium in breast cancer. While we did not observe any statistically significant differences in aluminium content across the breast it has to be emphasised that herein we measured whole breast tissue and not defatted tissue where such a distribution was previously noted. We are very confident that the method developed herein could now be used to provide accurate and reproducible data on the aluminium content in defatted tissue and oil from such tissues and thereby contribute towards our knowledge on aluminium and any role in breast cancer.
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Vaselli O, Higueras P, Nisi B, María Esbrí J, Cabassi J, Martínez-Coronado A, Tassi F, Rappuoli D. Distribution of gaseous Hg in the Mercury mining district of Mt. Amiata (Central Italy): a geochemical survey prior the reclamation project. ENVIRONMENTAL RESEARCH 2013; 125:179-187. [PMID: 23477568 DOI: 10.1016/j.envres.2012.12.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Revised: 11/15/2012] [Accepted: 12/04/2012] [Indexed: 06/01/2023]
Abstract
The Mt. Amiata volcano is the youngest and largest volcanic edifice in Tuscany (central-northern Italy) and is characterized by a geothermal field, exploited for the production of electrical energy. In the past Mt. Amiata was also known as a world-class Hg district whose mining activity was mainly distributed in the central-eastern part of this silicic volcanic complex, and particularly in the municipality of Abbadia San Salvatore. In the present work we report a geochemical survey on Hg(0) measurements related to the former mercury mine facilities prior the reclamation project. The Hg(0) measurements were carried out by car for long distance regional surveys, and on foot for local scale surveys by using two LUMEX (915+ and M) devices. This study presents the very first Hg(0) data obtained with this analytical technique in the Mt. Amiata area. The facilities related to the mining areas and structures where cinnabar was converted to metallic Hg are characterized by high Hg values (>50,000ngm(-3)), although the urban center of Abbadia San Salvatore, few hundred meters away, does not appear to be receiving significant pollution from the calcine area and former industrial edifices, all the recorded values being below the values recommended by the issuing Tuscany Region authorities (300ngm(-3)) and in some cases approaching the Hg background levels (3-5ngm(-3)) for the Mt. Amiata area.
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Wen X, Deng Q, Wang J, Yang S, Zhao X. A new coupling of ionic liquid based-single drop microextraction with tungsten coil electrothermal atomic absorption spectrometry. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 105:320-325. [PMID: 23318776 DOI: 10.1016/j.saa.2012.12.040] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 11/27/2012] [Accepted: 12/12/2012] [Indexed: 06/01/2023]
Abstract
In this work, an improved method of ionic liquid based-single drop microextraction (IL-SDME) preconcentration was firstly coupled with tungsten coil electrothermal atomic absorption spectrometry (W-coil ET-AAS) detection. The new coupling was developed and applied for the determination of ultra-trace cadmium. Experimental parameters influencing the performance of IL-SDME as well as instrumental conditions were studied systematically, including IL-drop volume, chelating agent concentration, pH, stirring rate and time, heating program of W-coil ET-AAS, flow rate of carrier gas. Under the optimal conditions, the limit of detection (LOD) for cadmium was 0.015 μg L(-1) (sampling amount on W-coil was 10 μL). The sensitivity enhancement factor was 42, while the improvement factor of LOD was 33. The established method was applied to determine cadmium in standard reference materials of rice and real water samples successfully. The developed IL-SDME-W-coil ET-AAS coupling represents a simple, green and highly sensitive method for cadmium determination.
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Li SX, Zheng FY, Li YC, Cai TS, Zheng JZ. Determination of zinc and copper in edible plants by nanometer silica coated, slotted quartz tube, flame atomic absorption spectrometry. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:11691-11695. [PMID: 23131082 DOI: 10.1021/jf304485q] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Nanometer SiO(2) was coated onto the inner wall of a slotted quartz tube atomizer (STAT) and then was used as a new atomizer (NSC- STAT) for the determination of Zn and Cu by flame atomic absorption spectrometry (FAAS). Compared to conventional STAT-FAAS, the analytical performance of NSC-STAT-FAAS was improved as follows: (a) the linear range of calibration curves was expanded from 30.0-200.0 ng mL(-1) to 5.0-400.0 ng mL(-1) for Zn, and from 100.0-1000.0 ng mL(-1) to 50.0-2000.0 ng mL(-1) for Cu; and (b) the characteristic concentration was decreased from 6.0 ng mL(-1)/1% to 2.7 ng mL(-1)/1% for Zn and from 25.0 ng mL(-1)/1% to 10.1 ng mL(-1)/1% for Cu. NSC-STAT-FAAS was applied for the determination of Zn and Cu in edible plants, including herbal medicine, marine algae, tomato leaves (NIST 1573), and apple leaves (NIST 1515).
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Dong ZH, Lu LX, Liu ZG. [Determination of heavy metals in ceramic food packaging containers by ICP-MS]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2012; 32:3139-3141. [PMID: 23387195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The direct determination method of heavy metals, Pb, Cd, Cr, Co, Ni, Zn, As and Sb in food packaging ceramics was studied by using inductive coupled plasma mass spectrometry (ICP-MS). Factors influencing the determination were also studied in detail. By choosing the optional operating parameters and appropriate isotopes of the element to be detected, the influence of mass spectrometry interference was conquered effectively. The detection limits were 0.023 microg x L(-1) for Pb, 0.004 microg x L(-1) for Cd, 0.030 microg x L(-1) for Cr, 0.025 microg x L(-1) for Ni, 0.012 microg x L(-1) for Sb, 0.180 microg x L(-1) for Zn, 0.017 microg x L(-1) for As, and 0.002 microg x L(-1) for Co. The recovery rates of the method were between 95.8% and 104.4%. The RSDs were between 1.1% and 3.3%. The method was simple, rapid, precise, convenient and suitable for daily inspection of import and export ceramic ware.
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da Silva DG, Portugal LA, Serra AM, Ferreira SLC, Cerdà V. Determination of mercury in rice by MSFIA and cold vapour atomic fluorescence spectrometry. Food Chem 2012. [PMID: 23200004 DOI: 10.1016/j.foodchem.2012.10.019] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In the present paper the use of a MSFIA system for determination of mercury in rice by cold vapour atomic fluorescence spectrometry (CV AFS) is proposed. The sample digestion is performed in a microwave oven using nitric acid and hydrogen peroxide. The experimental conditions for vapour generation were determined using a full two-level factorial design involving the following factors: nitric acid and tin chloride concentrations and sample flow rate. Employing the conditions optimised, the method allows the determination of mercury using the external calibration technique with aqueous standards. The reached limits of detection and quantification were 0.48 and 1.61 ng g⁻¹ respectively, and the precision (as relative standard deviation) was 3.28% and 1.56% for rice samples with a mercury content of 3.63 and 5.81 ng g⁻¹, respectively. The method accuracy was confirmed analysing a certified reference material of rice flour furnished by National Institute of Standard and Technology. The interference of nitrous acid and nitrous oxides are removed using potassium dichromate. The method was applied to mercury determination in twelve rice samples acquired in Palma de Mallorca (Spain) between the months of January and April of 2012. The mercury content found varied from 2.15 to 7.25 ng g⁻¹. These results agree with those reported by others authors.
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Mostafa-Gharehbaghi M, Mostafa-Gharabaghi P, Ghanbari F, Abdolmohammad-Zadeh H, Sadeghi GH, Jouyban A. Determination of selenium in serum samples of preterm newborn infants with bronchopulmonary dysplasia using a validated hydride generation system. Biol Trace Elem Res 2012; 147:1-7. [PMID: 22144015 DOI: 10.1007/s12011-011-9270-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Accepted: 11/09/2011] [Indexed: 10/15/2022]
Abstract
Bronchopulmonary dysplasia (BPD), also known as chronic lung disease, is one of the most challenging complications in premature newborn infants. Selenium plays a role in antioxidant system by protecting cell membranes and neutralizing the deleterious effects of free radicals. The aim of this study was to determine the relationship between selenium concentration and incidence of bronchopulmonary dysplasia using a validated analytical method. Umbilical cord blood and blood samples 30 days after the birth were collected from 38 preterm newborn infants with gestation age of 32 weeks or less, and the separated serums were kept at -70°C until analysis time. Selenium concentration of serum was determined using an atomic absorption spectrophotometer. The method was validated on the basis of standard validation techniques. The analytical method was linear in the range of 1 to 500 μg/L with the limit of detection of 0.4 μg/L. Samples were collected from 38 infants whose gestation age was 32 weeks or less. The blood samples were collected from the umbilical cord blood at birth in 19 cases. In 25 cases, blood samples were collected 1 month after birth. Of the 15 patients diagnosed with BPD, 10 were boys (p = 0.02). The mean serum selenium concentration was not different at birth between patients with and without BPD, but it was significantly lower at 30 days after birth in patients with BPD (38.5 ± 14.1vs. 45.4 ± 18.7 μg/L, p = 0.02). Preterm newborn infants with BPD had lower serum selenium concentrations 1 month after birth.
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Domínguez MA, Grünhut M, Pistonesi MF, Di Nezio MS, Centurión ME. Automatic flow-batch system for cold vapor atomic absorption spectroscopy determination of mercury in honey from Argentina using online sample treatment. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:4812-4817. [PMID: 22540901 DOI: 10.1021/jf300637b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
An automatic flow-batch system that includes two borosilicate glass chambers to perform sample digestion and cold vapor atomic absorption spectroscopy determination of mercury in honey samples was designed. The sample digestion was performed by using a low-cost halogen lamp to obtain the optimum temperature. Optimization of the digestion procedure was done using a Box-Behnken experimental design. A linear response was observed from 2.30 to 11.20 μg Hg L(-1). The relative standard deviation was 3.20% (n = 11, 6.81 μg Hg L(-1)), the sample throughput was 4 sample h(-1), and the detection limit was 0.68 μg Hg L(-1). The obtained results with the flow-batch method are in good agreement with those obtained with the reference method. The flow-batch system is simple, allows the use of both chambers simultaneously, is seen as a promising methodology for achieving green chemistry goals, and is a good proposal to improving the quality control of honey.
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Karpova EA, Malysheva AG, Ermakov AA, Sidorenkova NK. [Electrothermal atomic absorption determination of arsenic in plants and plant products]. GIGIENA I SANITARIIA 2012:78-81. [PMID: 22712335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The authors have developed the optimal temperature-time parameters of electrothermal atomic absorption determination of arsenic in plants after their acid predigestion. The matrix modifier is 1% nickel nitrate or palladium nitrate solution. Cuvettes (ovens) are simple, made of porous or pyrolytic graphite. The analytical program is suitable for both spectrometers with Zeeman and deuterium background correction. The correctness of the procedure has been estimated from the results of analysis of state reference samples certified for their arsenic content. The coefficient of variation was 20-35% for the concentration range of 0.02-0.2 mg/kg.
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Porento M, Sutinen V, Julku T, Oikari R. Detection of copper in water using on-line plasma-excited atomic absorption spectroscopy (AAS). APPLIED SPECTROSCOPY 2011; 65:678-683. [PMID: 21639990 DOI: 10.1366/10-06051] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A measurement method and apparatus was developed to measure continuously toxic metal compounds in industrial water samples. The method was demonstrated by using copper as a sample metal. Water was injected into the sample line and subsequently into a nitrogen plasma jet, in which the samples comprising the metal compound dissolved in water were decomposed. The transmitted monochromatic light was detected and the absorbance caused by copper atoms was measured. The absorbance and metal concentration were used to calculate sensitivity and detection limits for the studied metal. The sensitivity, limit of detection, and quantification for copper were 0.45 ± 0.02, 0.25 ± 0.01, and 0.85 ± 0.04 ppm, respectively.
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