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[Display omitted] • Development of a sensitive CRISPR/Cas12a-based amplification-free nanoparticle counting method for detection of AFB1. • The first report of the ICPMS single particle counting-based CRISPR/Cas12a biosensing study. • This method has been successfully applied to determination of AFB1 in food matrices (peanut oil, beer, and wheat meal). CRISPR (clustered regularly interspaced short palindromic repeats) and CRISPR-associated protein (Cas) have gained extensive applications in bioassays. However, CRISPR-based detection platforms are often hampered by limited analytical sensitivity, while nucleic acid-based amplification strategies are usually indispensable for additional signal enhancement with potential risks of amplification leakages. To address these challenges, an amplification-free CRISPR-based bioassay of aflatoxin B1 (AFB1) was proposed by applying single nanoparticle counting. Single-particle mode inductively coupled plasma mass spectrometry (Sp-ICPMS) has been regarded as a sensitive tool for nanoparticle counting since one nanoparticle can generate considerable signals above backgrounds. With AFB1, activator strands were introduced to initiate the trans -cleavage of CRISPR/Cas12a for cutting the nanoparticles-tagged-magnetic beads, which were transduced to nanoparticle count signals after separation. Finally, a pico-mole level limit-of-detections (LODs) with moderate selectivity was achieved. Certified reference materials (CRMs) analysis and recovery tests were conducted with promising results. To our best knowledge, this is the first report of the single particle counting-based CRISPR/Cas12a biosensing study. [ABSTRACT FROM AUTHOR]

The release of certain metallic constituents within some dental implants could contribute to peri-implantitis and mucositis. While the release rate into surrounding bones and tissues may be dependent on the biocompatibility of dental materials and their designs, the patient's oral hygiene and even the prevalence of certain resident oral bacteria may also affect the service lives of these dental implants by altering their gross corrosion rates. In this study, the levels of Fe, Cr, and Ni released during microbiologically induced intergranular corrosion of medical grade 316L stainless-steel dental material are measured across defined culture durations. Porphyromonas gingivalis , a prominent component of the oral microbiome known to associate with periodontitis and peri-implantitis, is the test bacterium in this study. From the evidence obtained from electrochemical and surface investigations in artificial salivary culture media, dental substates corroded significantly upon maturation of bacterial growth. Corrosion was accompanied by higher levels of metal ion release at extended culture duration. About 1.5 and 9.5 μg/cm2 of Ni and Cr were leached from the metal alloy after a 30-day exposure to the bacterial culture relative to the control; Fe was released 30 times more in the former. This study highlights how oral metal contact influences the corrosion of metallic dental implants (e.g., stainless-steel crowns) in patients infected by certain resident oral bacterium. • Higher amounts of metallic leachants released from dental substrates in salivary culture. • Higher levels of Fe were observed in the culture compared to Ni and Cr. • The above trend continued with and without bacterial inoculation. • Bacterial growth accelerated MIC accompanied by increased j corr and lowered R p. • Intergranular corrosion intensified with evolving volatile sulfur compounds. [ABSTRACT FROM AUTHOR]

The palm-pruning leaves considered as valuable source for low cost adsorbent materials. Such application, enhance the environmental conditions by reducing the bad effects from un-managed palm-pruning leaves such as spreading insects. Herein, the palm-pruning leaves were treated with by water and acid washing to produce cleaned palm leaves (CPL) and then impregnation with iron(III) chloride and thermally treated to produce palm leaves/iron oxide- nanocomposite (PL/IO-NC). The prepared materials were applied for adsorption of some toxic metal ions from solutions. The original palm-pruning leaves as well as the treated adsorbent were characterized by SEM, EDS, FTIR, XRD. Results showed the formation of spots iron oxide nanoparticles onto the palm-pruning leaves. The efficiency of the treated adsorbent for uptake of Mn(II), Co(II) and Pb(II) was studied in term of kinetic, isotherm and thermodynamic to optimize and evaluate the effectiveness of the palm-pruning leaves treatment. The adsorption data was found to be more comfortable with Second order kinetic-model while the isotherm of Langmuir wasn't suitable and the adsorption data was in agreement with Freundlich assumption. The values of ΔG° in the range (−5.8 to −3.5 kJ/mol) for Mn(II), (−4.2 to −2.1 kJ/mol) for Co(II), (−3.4 to −2.3 kJ/mol) for Pb(II), confirm the confirm the spontaneous and physical nature of the adsorption process. [ABSTRACT FROM AUTHOR]

New Year's Eve fireworks represent one of the most unusual atmospheric pollution events in the course of a year. A majority of particles aerosolized by burning of fireworks consist of metals and their compounds used in firework displays. In this study, ambient particulate matter was sampled using a 14 stage cascade impactor in two European cities during turn of the years 2016/17 and 2017/18. Concentrations of 33 elements were determined by inductively coupled plasma mass spectrometry. To assess the impact of New Year's Eve fireworks on ambient air quality, chemically resolved size distributions of particles with diameters between 15 nm and 10 μm collected during fireworks episodes were compared to ones collected in normal winter weeks. For some metals a distinct shift of their concentration maximum related to fireworks could be observed, which is in between the maxima for accumulation and coarse mode particles. Concentrations of these elements (Sr, Ba, Mg, Bi, Al, Cu and K) were also higher during weeks with fireworks episodes than during control weeks. Although New Year's Eve fireworks only take place once a year, these results show that air pollution caused by fireworks can be a potential health risk, especially for people with pre-existing diseases. Unlabelled Image • Fireworks can change the size resolved element distributions in urban aerosols. • Elements are enriched in between the maxima for accumulation and coarse mode. • Metals like Mg, Al, Cu, Sr and Ba become more respirable during fireworks episodes. • Higher health risk because of smaller particles [ABSTRACT FROM AUTHOR]

Organic and inorganic colloids play important roles governing the speciation, transport, and bioaccessibility of trace elements in aquatic systems. These carriers are especially important in the boreal zone, where rivers that contain high concentrations of iron and organic matter are prevalent. The distribution of trace elements amongst different colloidal species (or “speciation profile”) can therefore be useful as a fingerprint to detect different trace element sources and for tracking colloid transformations, with implications for bioaccessibility. Asymmetrical flow field-flow fractionation coupled to an inductively coupled plasma mass spectrometer was applied to detect the source of trace elements based on their speciation profile along a 125-km stretch of a large river in the Canadian boreal forest. Both the concentration and proportion of bound trace elements were increased by tributary inputs: bound As, Co, Fe, Mn, Pb, U, and Zn increased monotonically from upstream to downstream, increasingly resembling the speciation profile of tributaries. Principal component (PC) analysis also revealed tributary contributions of bound Cu, Ni, Th, V, and Y reflecting their higher concentrations in tributaries, and PC scores also increased monotonically from upstream–downstream. Monotonically decreasing concentrations of mainly ionic and small (i.e.

The arsenic speciation was determined in macrofungi of the Ramaria genus with HPLC coupled to inductively coupled plasma mass spectrometry. Besides arsenic species that are already known for macrofungi, like arsenobetaine or arsenocholine, two compounds that were only known from marine samples so far (trimethylarsoniopropanate and dimethylarsinoylacetate) were found for the first time in a terrestrial sample. An unknown arsenical was isolated and identified as homoarsenocholine. This could be a key intermediate for further elucidation of the biotransformation mechanisms of arsenic. [ABSTRACT FROM AUTHOR]

This study assesses the impact of the farming system on the levels of copper, zinc, arsenic, cadmium, lead and mercury in pig tissues from three types of production (Organic (n = 28), Label Rouge (n = 12) and Conventional (n = 30)) randomly sampled in different slaughterhouses. All the concentrations were below regulatory limits. In muscles, Cu, Zn and As were measured at slightly higher levels in organic samples but no differences between organic and Label Rouge was observed. Livers from conventional and Label Rouge pig farms exhibited higher Zn and Cd contents than the organic ones, probably due to different practice in zinc or phytase supplementation of fattening diets. Principal component analysis indicated a correlation between Cu and As concentrations in liver and carcass weight, and between Zn and Cd liver levels and lean meat percentage. The linear discriminant analysis succeeded in predicting the farming process on the basis of the lean meat percentage and the liver Cd level. [ABSTRACT FROM AUTHOR]

The total arsenic concentration and the arsenic speciation in urine and feces samples of the two Giant Pandas living at Vienna zoo and of their feed, bamboo, were determined with ICPMS and HPLC-ICPMS. Urine was the main excretion route and accounted for around 90% of the ingested arsenic. The urinary arsenic concentrations were very high, namely up to 179 μg/L. Dimethylarsinic acid (DMA) was the dominating arsenic compound in the urine samples and ranged from 73 to 92% of the total arsenic, which is unusually high for a terrestrial mammal. The feces samples contained around 70% inorganic arsenic and 30% DMA. The arsenic concentrations in the bamboo samples were between 16 and 920 μg/kg dry mass. The main arsenic species in the bamboo extracts was inorganic arsenic. This indicates that the Giant Panda possesses a unique way of very efficiently methylating and excreting the provided inorganic arsenic. This could be essential for the survival of the animal in its natural habitat, because parts of this area are contaminated with arsenic. [ABSTRACT FROM AUTHOR]

Recent developments in high-energy accelerator mass spectrometry (AMS) and low-energy inductively coupled plasma mass spectrometry (ICPMS) made them the most sensitive techniques for ultra low-level analysis of 238 U and 232 Th. Detection limits below 1 nBq g −1 for analysis of these radionuclides in construction materials were obtained. The most important development in the radiometric sector was operation of HPGe detectors in underground laboratories where detection limits of about 1 µBq kg −1 were obtained. Specific features of radiometric, mass spectrometry and neutron activation techniques for ultra low-level radionuclide measurements are discussed, and obtained results for analysis of radiopure materials prepared for underground experiments are compared. [ABSTRACT FROM AUTHOR]

Pu isotopes in various foods were detected using a quadrupole ICPMS and Aridus II desolvation nebulizer. The method has ability to detect 239 Pu and 240 Pu at concentrations of ~52 pg/kg (0.12 Bq/kg) and ~9.5 pg/kg (0.08 Bq/kg) as well as 240 Pu/ 239 Pu ratio in <8 h after receiving the samples. Foods were wet-ashed followed by DGA extraction for eliminating matrix, isobaric, and polyatomic interferences. A UH + formation rate <10 −5 and a 5-fold enhanced sensitivity for Pu was achieved after system optimization. [ABSTRACT FROM AUTHOR]

This paper considers the current status, the changes, and the challenges of food authentication and traceability with specific reference to the Asian and Australian perspective. Building on the experience of the author (who has presented at seven International Atomic Energy Agency Regional Training Courses in Pakistan, Malaysia, Indonesia, Vietnam and The Philippines), and some relevant case studies, the use of chemical analysis for identification of the origin and potential adulteration of foods and beverages will be discussed. Examples of applications of these techniques include: 1) detecting passing off produce from country A as coming from other countries or conversely passing off non-country A produce as if they originated from country A, and 2) detecting, and prosecuting, people who were taking seafood from a protected marine area and claiming it came from another area. Some reasons why countries in the Asian and Australian region are interested in using these techniques to investigate food authentication and traceability include: desire to have confidence in what we are eating, desire to pay a correct price for the product, health and food safety issues, prevention of criminal activities, and safeguarding environments by preventing the spread of disease and invasion of non-indigenous species. Food and food security is a growing global concern and having a reliable, confirmable, diet is a daily concern for inhabitants of the Asian and Australian region. [ABSTRACT FROM AUTHOR]

Aims p-tertbutylcalix [4] arene loaded nanoemulsion has been designed, characterized and evaluated for skin decontamination of radionuclides of interest in nuclear and radiological emergencies. Further, nanoemulsion was evaluated for Ex-vivo complexation, skin permeation, interaction and cytodermal toxicity. Materials and methods Ex-vivo skin complexation studies were conducted using High-resolution sector field inductively coupled plasma mass spectroscopy (HR-SF-ICPMS). Skin studies at dermal and cyto-dermal level have been carried out using techniques such as florescence microscopy, Differential scanning calorimetry (DSC), Flow cytometry, Confocal microscopy, Prestoblue and Comet assay. Key findings HR-SF-ICPMS study confirmed > 95% complexation of surrogate nuclides of thallium and Iodine applied on excised rat skin mounted over Franz diffusion cell. Temporal analysis of aliquots obtained from Franz diffusion cell using UV–Vis absorption spectroscopy indicated that only 3.37% of formulation permeates through the skin. Skin penetration study of rhodamine 123 nanoemulsion carried out using florescence microscopy confirmed that formulation remains localised in epidermis of rat skin. DSC data confirmed skin compatibility of nanoemulsion, as no lipid extraction was observed from skin. In-vitro cell viability and cellular uptake assays performed on human skin fibroblasts prove no cellular uptake and cytotoxic effects. Comet assay, cell cycle arrest, and apoptosis-inducing mechanistic studies prove that prepared nanoemulsion is safe at cellular level. Significance Taken together, data indicate that p-tertbutylcalix [4] arene nanoemulsion is both effective and safe formulation to use on skin for radio-decontamination. [ABSTRACT FROM AUTHOR]

The mass and volume concentration of nanoplastics is extremely low, but incredibly high in terms of surface area; this is expected to increase their toxicity through the ab/adsorption and transport of chemical co-pollutants such as trace metals. In this context, we studied the interactions between nanoplastics model materials functionalized with carboxylated groups, with either smooth or raspberry-like surface morphologies, and copper as representative of trace metals. For this purpose, a new methodology, using two complementary surface analysis techniques: Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) and X-ray Photoelectron Spectroscopy (XPS) was developed. In addition, inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify the total mass of sorbed metal on the nanoplastics. This innovative analytical approach from the top surface to the core of nanoplastics demonstrated not only the interactions with copper at the surface level, but also the ability of nanoplastics to absorb metal at their core. Indeed, after 24 h of exposition, the copper concentration at the nanoplastic surface remained constant due to saturation whereas the copper concentration inside the nanoplastic keeps increasing with the time. The sorption kinetic was evaluated to increase with the density of charge of the nanoplastic and the pH. This study confirmed the ability of nanoplastics to act as metal pollutant carriers by both adsorption and absorption phenomena. [Display omitted] • The capability of nanoplastics to act as copper vectors has been evaluated. • XPS, ToF-SIMS and ICP-MS were used to discriminate and estimate ad/absorption. • The effects of NPT surface functionalization and exposure conditions were studied. [ABSTRACT FROM AUTHOR]

Fluids play an important role in many geological/ore genetic processes. The composition of the hydrothermal fluid is a critical but often unknown parameter that controls the mobilization of elements and their concentration into mineralized zones. In-situ analyses of fluid inclusions trapped in minerals using laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) is a powerful tool to constrain the composition of the mineralizing fluid. The LA-analysis of fluid inclusions is analytically challenging due to potential mismatch of matrix between fluid inclusions and solid NIST reference glasses commonly used as calibrating standards. We conducted experiments to evaluate the effects of using solid and liquid as calibrating standard on data quality during ablation of liquid/mineral fluid inclusions, as well as the effects of variable energy fluence and repetition rate on the time-dependent elemental fractionation. The LA-analyses of liquids (with NaCl matrix) when standardized against another solution has lower precision and accuracy compared to standardization with NIST reference glasses. The 193 nm laser has little matrix effect and causes negligible elemental fractionation. The trace element concentrations of liquids retrieved by external standardization with NIST reference glass has better accuracy and precision. Higher laser fluence (8.5 J/cm2) produces better sensitivity, lesser time-dependent elemental fractionation, lower detection limits, and better accuracy/precision and is recommended for ablation of natural fluid inclusions or liquids. We tested our preferred analytical protocol by analyzing the composition of quartz-hosted fluid inclusions from the Malanjkhand copper deposit in central India. The LA-ICPMS measurements of the fluid inclusions help to establish that the mineralizing fluid had high concentrations of K, Rb, and Cs. Fluid inclusions from the Malanjkhand copper deposit are trapped from fluids that are dominantly of magmatic origin, sourced from highly differentiated granitic magmas. The NIST glasses are appropriate calibrating standards for ablation of synthetic liquids as well as natural fluid inclusions. [Display omitted] • LA-ICPMS measurement of liquid is more precise/accurate at higher laser fluence. • Bracketing of liquid measurements by NIST glass gives reproducible/accurate results. • Fluid inclusions from Malanjkhand Cu-deposit has high K, Rb, Cu, Cs concentrations. • Mineralizing fluid of magmatic origin sourced from differentiated granitic melt. [ABSTRACT FROM AUTHOR]

• The same-sized AgNPs with different coatings were separated by BCyElFFF. • NOM corona on AgNPs was identified by changes in their elution times in BCyElFFF. • NOM corona structures identified were in good agreement with HRTEM results. • NOM corona significantly improved the survival rate of E. coli exposed to AgNPs. Natural organic matter (NOM) readily interacts with nanoparticles, leading to the formation of NOM corona structures on their surface. NOM corona formation is closely related to the surface coatings and bioavailability of nanoparticles. However, the mechanism underlying NOM corona formation on silver nanoparticles (AgNPs) remains largely unknown due to the lack of effective analytical methods for identifying the changes in the AgNP surface. Herein, the separation ability of biased cyclical electrical field-flow fractionation (BCyElFFF) for same-sized polyvinyl pyrrolidone-coated and poly(ethylene glycol)-coated silver nanoparticles (AgNPs) with different electrophoretic mobilities was evaluated under various electrical conditions. Then, the mechanism behind the NOM corona formation on these AgNP surfaces was elucidated based on the changes in the elution time and off-line characterization of the collected fractions during their elution time in a BCyElFFF run. Finally, the survival rates of E. coli exposed to polyvinyl pyrrolidone-coated and poly(ethylene glycol)-coated AgNPs with or without NOM collected during repeated BCyElFFF runs were observed to increase with increasing NOM concentration, clearly demonstrating the negative effect of NOM corona structures on the bioavailability of AgNPs. These findings highlight the powerful separation and isolation ability of BCyElFFF in studying the transformation and fate of nanoparticles in aqueous environments. [Display omitted] [ABSTRACT FROM AUTHOR]

An improved matrix separation method has been described to characterize ultrapure germanium of 8N (99.999999%) purity. In this method, temperature of the reaction vessel in which in-situ generated chlorine gas reacts with germanium solid material directly is optimized to quantitatively remove Ge matrix from all its impurities. Optimized reaction temperature has been found to be 230±5 °C. Recovery studies on more than 60 elements have been carried out at the optimized temperature. Recoveries of all the analytes except As, Se, Sn, Hg, Tl are found to be quantitative. The method has been examined for various amounts of Ge material and found to be suitable even for 10 g of Ge sample and provides low parts per billion and trillion levels of process blanks. Determination of concentrations of impurities has been done by inductively coupled plasma quadrupole mass spectrometer (ICP-QMS) and high resolution continuum source graphite furnace atomic absorption spectrometer (HR-CS-GFAAS). In the absence of certified reference materials for ultrapure germanium, accuracy of the proposed method is established by spike recovery tests. Precision of this method is found to vary from 7% to 50% for concentrations between 4 and 0.004 ng g −1 . Limits of detection (LOD) for the target analytes are found to be between 6 and 0.011 ng mL −1 or 1.8–0.003 ng g −1 for the proposed procedure. The method has been successfully applied for that characterization of ultrapure germanium material of 8N purity. [ABSTRACT FROM AUTHOR]

Apatite, the most abundant phosphate mineral in the Earth's crust and uppermost mantle, is able to accept a wide variety of trace elements into its crystal structure. Many of these trace element substitutions are below the detection limit of Electron Microprobe Analysis, but can be determined by laser-ablation inductively coupled plasma mass spectrometry (LA-ICPMS). LA-ICPMS elemental abundance determinations typically employ sample-standard bracketing using either standard glasses or an appropriate matrix-matched reference material. In this study we have undertaken laser ablation (> 3000 analyses) and low-blank solution Q(quadrupole)-ICPMS trace-element analyses on crushed 150–300 μm aliquots of Durango and McClure Mountain apatite to assess the accuracy of apatite elemental abundance determinations when using NIST 612 standard glass as the primary LA-ICPMS trace element standard. An accuracy (relative to the solution data) and precision of < 5% can be obtained for most trace elements (Y, the REE, Sr, Mn, V, Th and U) in LA-ICPMS analyses of crushed Durango separates; the McClure Mountain data are similarly accurate for most trace elements but yield larger intra-crystal variability. Durango raster and image mapping experiments demonstrate some Durango crystals are more homogenous than others; the raster experiments also show that Durango typically exhibits less zoning parallel to the C-axis compared to perpendicular to the C-axis. A protocol for developing a homogenous Durango apatite trace-element reference material is suggested, and involves slicing the interior portions of several Durango crystals parallel to the C-axis, undertaking rapid LA-ICPMS raster experiments to characterize trace-element zoning, crushing the most homogenous crystal to 150–300 μm and determining its trace-element contents by low-blank solution ICPMS. This generic approach can easily be modified and applied to characterize other natural LA-ICPMS mineral standards. [ABSTRACT FROM AUTHOR]

The extraction and measurement of selenomethionine (SeMet) and selenocysteine (SeCys) in fish muscle and liver tissues were evaluated. Preliminary experiments were undertaken with marine certified reference materials. NRCC TORT 1/2 Lobster hepatopancreas, NRCC DOLT 2/3; Dogfish liver and NIST 1566 a/b Oyster tissue were extracted using aqueous leaching, enzymatic hydrolysis and acid hydrolysis with ultrasound, microwave assisted heating and conventional heating using a hybridisation oven. High Se recoveries were obtained with the use of methanesulfonic acid as an extractant (89–92%); however, the low pH required for extraction is not compatible with most HPLC columns and dilution is required to analyse extracts that precluded the measurement of Se in samples from relatively uncontaminated environments. As well, Se species (SeMet and SeCys) degrade with the use of highly acidic extractants. Enzymatic hydrolysis with protease type XIV gave good recoveries (63–67%), but only SeMet was stable in the extract. As SeCys was not stable, a derivatisation step using iodoacetamide to form a stable carboxymethylated complex was used prior to enzymatic hydrolysis. Conventional heating at 37 °C for 20 h and microwave assisted heating at 45°C for 45 min gave similar recoveries for CRMs but conventional heating gave slightly better recoveries for fish tissues. Two separate complementary methods were developed for the measurement of SeMet and SeCys in marine fish tissues; SeMet was measured after protease XIV hydrolysis and analysis using anion or cation exchange chromatography-ICPMS, while for the measurement of SeCys a carbamidomethylation derivatisation procedure prior to the protease hydrolysis was used and the separation of the species was carried out using size exclusion chromatography, followed by C8 ion-pair reversed-phase chromatography with ICPMS. Recoveries of SeMet and SeCys added to CRMs and fish tissues were 97 ± 9% and 84 ± 9% respectively. [ABSTRACT FROM AUTHOR]

A direct solid sampling technique has been developed based on a pulsed radio-frequency discharge (RFD) in mixture of N 2 and Ar environment at atmospheric pressure. With an averaged input power of 65 W, a crater with the diameter of 80 μm and depth of 50 μm can be formed on sample surface after discharge for 1 min, suggesting the feasibility of the pulsed RFD for sampling nonconductive solids. Combined with inductively coupled plasma mass spectrometry (ICPMS), this technique allows to measure elemental composition of solids directly with relative standard deviation (RSD) of ~ 20%. Capability of quantitative analysis was demonstrated by the use of soil standards and artificial standards. Good calibration linearity and limits of detection (LODs) in range of 10 − 8 –10 − 9 g/g were achieved for most elements. [ABSTRACT FROM AUTHOR]

Wild growing phytocenosis from three different areas near former gold or silver mines—Kutná Hora, Roudný and Nalžovské Hory (Czech Republic) were investigated for total arsenic and arsenic species concentrations. The most abundant plant families that occurred were Fabaceae , Lamiaceae , Asteraceae , Poaceae and Plantaginaceae . Several plant species such as Achillea millefolium L. ( Asteraceae ), Anthoxanthum odoratum L. ( Poaceae ), Plantago lanceolata L. ( Plantaginaceae ) are widespread and could be found in all of the investigated areas. Total As concentrations in aboveground biomass of plants growing on those three sites were determined by an inductively coupled plasma mass spectrometry (ICPMS) and ranged from 0.02* mg As kg −1 ( Stellaria spp.) to 39.30 ± 6.32 mg As kg −1 ( Daucus carota L.). The concentrations seem to be dependent on both plant species and physico-chemical soil properties. For the arsenic speciation a high performance liquid chromatography (HPLC) online connected with the ICPMS was used. Results have shown that arsenite and arsenate are the prevalent arsenic compounds. Methylarsonic acid (MA), dimethylarsinic acid (DMA), arsenobetaine (AB), arsenocholine (AC), tetramethylarsonium ion (TETRA), and trimethylarsine oxide (TMAO) were identified as minor species. Arsenobetaine was found at significant concentrations in Carex praecox Schreb. (28% of the extractable As amount) and P. lanceolata L. (1.2% of the extractable As amount). [ABSTRACT FROM AUTHOR]

The present study reports arsenic analysis in Lentinula edodes , Agaricus bisporus and Pleurotus ostreatus before and after being cooked. Furthermore, arsenic in raw and cooked mushroom was determined in the gastric and gastrointestinal bioaccessible fractions obtained after simulating human digestion by means of an in vitro physiologically based extraction test (PBET). Several certified reference materials (SRM 1568a, SRM 1570a, CRM 7503-a, BC211 and IPE-120) were analysed to evaluate the proposed methods. Total arsenic content was 1393, 181 and 335 μg As kg −1 for L. edodes , A. bisporus and P. ostreatus , respectively, and decreased by between 53% and 71% in boiled mushroom and less than 11% in griddled mushroom. High bioaccessibility was observed in raw, boiled and griddled mushroom, ranging from 74% to 89% and from 80% to 100% for gastric and gastrointestinal extracts, respectively, suggesting the need to consider the potential health risk of consumption of the mushrooms analysed. [ABSTRACT FROM AUTHOR]

Scanning Mobility Particle Sizer (SMPS) and Inductively Coupled Plasma Mass Spectrometry (ICPMS), complemented by a Rotating Disk Diluter (RDD) to a hyphenated RDD-SMPS-ICPMS measuring setup, allow online and simultaneous determination of size distribution and elemental composition of gas borne nanoparticles. This coupling strategy offers high flexibility in terms of dealing with different aerosols, loaded with metallic nanoparticles. The capabilities of such an instrument are demonstrated on uniformly composited metal aerosols, as well as an aerosol mixture containing smaller gold and larger silver nanoparticles. The size resolved ICPMS intensity curves correlate very well to the size distributions, determined by the coupled SMPS, and also to those from a non-modified reference SMPS instrument. Particulate iron, gold, and silver are detected with SMPS scan durations of a few minutes, and nanoparticles of different sizes and compositions are successfully distinguished. Sensitivity and limit of detection, related to particle number and mass concentration, are determined for several elements and particle diameters. [ABSTRACT FROM AUTHOR]

Modified matrix volatilization (MV) method has been described to characterize high purity germanium material of 7 N (99.99999%) purity. Transport of both, the chlorine gas generated in-situ in this method and the argon gas (carrier) is fine controlled by means of a mass flow controller. This enabled both uniform reaction of chlorine gas with the germanium matrix and smooth removal of germanium matrix as its chloride. This resulted in improvement in the reproducibility of the analytical results. The use of quartz reaction vessel has lead to the reduction in the process blank levels. The combined effect of these modifications in the MV setup has resulted in very consistent and low process blanks and hence improved detection limits of this method. Applicability of the method has been expanded to rare earth elements and other elements after examining their recoveries. The quantification is done by using inductively coupled plasma quadrupole mass spectrometer (ICP-QMS) and continuum source graphite furnace atomic absorption spectrometry (CS-GFAAS). In the absence of certified reference materials for high pure germanium, the accuracy of the method is established by spike recovery tests. The precision of the method has been found to vary from 1 to 30% for concentrations between 1 and 30 ng g −1 . The limits of detection (LOD) for the target analytes are found to be between 18 and 0.033 ng g −1 . [ABSTRACT FROM AUTHOR]

Physical and chemical characterization of gas borne particles in the nanometer to sub‐micrometer size range includes knowledge about particle size distribution and chemical composition, possibly with a high time resolution. However, most of the available techniques are offline methods and/or not able to provide such physical and chemical information simultaneously. Scanning Mobility Particle Sizer (SMPS) is a well-established and widely used technique for determining size distribution and number concentration of such particles, within scan durations of a few minutes. Inductively Coupled Plasma Mass Spectrometry (ICPMS) is a highly sensitive multi-element technique, allowing the determination of elemental composition with excellent detection limits and a wide dynamic concentration range. In this work, SMPS and ICPMS were coupled to one hyphenated system which allows achieving on-line and simultaneously size and chemical information with SMPS-typical time resolutions. A Rotating Disk Diluter was used as sample introduction interface, and the SMPS flow concept was re-designed to fulfill the requirements of both different analytical methods. The developed setup was successfully tested with a model aerosol containing airborne silver nanoparticles. Proper SMPS operation under argon atmosphere instead of air was validated. The presented setup was applied to scan the particle size range from 7 to 156 nm within 120 s. Similar sensitivities and efficiencies compared to that of state-of-the-art SMPS and ICPMS instruments were achieved. [ABSTRACT FROM AUTHOR]

We describe a HPLC/mass spectrometry method for the simultaneous determination of glycine betaine and arsenobetaine in biological samples. The sample preparation included a water/methanol extraction followed by clean-up of extracts on a strong cation-exchange resin; the HPLC system consisted of a cation-exchange column with an ammonium formate buffer solution as mobile phase. Glycine betaine and arsenobetaine were quantified in a single chromatographic run by splitting the HPLC flow with an adjustable flow splitter and detecting glycine betaine selectively by electrospray MS in the positive single ion monitoring mode at m/z 118, and arsenobetaine with the arsenic-selective detector ICPMS at m/z 75. The proposed method was validated for arsenobetaine by analysis of CRM Dorm-2, and for glycine betaine by spiking the CRM Dorm-2 with a defined amount of glycine betaine. Finally, the developed method was applied to determine glycine betaine/arsenobetaine ratios in single specimens of four species of marine fish and one species of freshwater fish. [ABSTRACT FROM AUTHOR]

A depth profile technique has been developed for ultrathin layer analysis by combining a pulsed micro-discharge device with inductively coupled plasma mass spectrometry (ICPMS). With a tungsten needle as the anode and the sample as the cathode, a local micro-plasma was formed in the 50 μm discharge gap, which contributed to the ablation of the sample. We analyzed a series of Ni coating samples with thicknesses of 5, 10, 15, and 20 nm in this study. Although the micro-discharge was shown to be an arc, pulsed mode operation provided an extra control over the power output and the discharge time that enabled precision ablation of submillimeter in lateral scale and 0.6 nm in depth per pulse. A further attempt was made to demonstrate the ability in thickness determination using the calibration curve for layers of different thicknesses. Our results show that the pulsed micro-discharge could directly ablate a solid sample under ambient conditions and that it is an effective low-cost method for depth profiling of nanometer thin layers. [ABSTRACT FROM AUTHOR]

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 (1 h vs. 3 h) 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 200 μg L −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 1.6 μg L −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. [ABSTRACT FROM AUTHOR]

Three analytical methods were evaluated for hexavalent and trivalent chromium analyses in the presence of natural organic matter (NOM) and alkalinity. Each method was tested using a simulated tap water with 1 μg L-1 Cr(VI) and 0.8 μg L-1 Cr(III) and several concentrations of NOM and/or alkalinity. An ion chromatograph with post column reaction cell conforming to USEPA Method 218.7 could accurately quantify Cr(VI) in the presence of up to 8 mg C L-1 NOM and up to 170 mg L-1 as CaCO3 alkalinity, and no oxidation of chromium was observed when 0.8 μg L-1 Cr(III) was also present. A high-performance liquid chromatography coupled with inductively coupled plasma (HPLC-ICPMS) method and a field speciation method were also evaluated. Each of these methods was unaffected by the presence of alkalinity; however, the presence of NOM created issues. For the HPLC-ICPMS method, as the concentration of NOM increased the recovery of Cr(VI) decreased, resulting in a 'false negative' for Cr(VI). However, for the field speciation method, Cr(III) was complexed by NOM and carried through the ion exchange column, resulting in a 'false positive' for Cr(VI). [ABSTRACT FROM AUTHOR]

Abstract: Monitoring of PGEs content in the natural samples is a crucial point in the environment science since catalytic car converters have been introduced. In the presented paper application of a very sensitive voltammetric method for determination of traces of Pt and Rh in the environmental samples contaminated by automobile exhausts is discussed. Voltammetric measurements were carried out in the supporting electrolyte containing formaldehyde and semicarbazide. PGEs were separated from the digested solutions of soils or quartz samples, collected from monitoring plots—by applying an ion-exchange resin Cellex-T. Pt was very effectively separated from the matrix approaching nearly 100% recovery after its elution by hydrochloric acid. Moreover the conditions of soil and quartz samples digestion were discussed. To validate the obtained result an independent analytical method—ICP MS was applied and analysis of certified reference material road dust 723—was completed. [Copyright &y& Elsevier]

Abstract: The concentrations of eight trace elements: lead (Pb), cadmium (Cd), chromium (Cr), manganese (Mn), cobalt (Co), arsenic (As), bismuth (Bi) and molybdenum (Mo), in chocolate, cocoa beans and products were studied by ICPMS. The study examined chocolate samples from different brands and countries with different concentrations of cocoa solids from each brand. The samples were digested and filtered to remove lipids and indium was used as an internal standard to correct matrix effects. A linear correlation was found between the level of several trace elements in chocolate and the cocoa solids content. Significant levels of Bi and As were found in the cocoa bean shells but not in the cocoa bean and chocolate. This may be attributed to environmental contamination. The presence of other elements was attributed to the manufacturing processes of cocoa and chocolate products. Children, who are big consumers of chocolates, may be at risk of exceeding the daily limit of lead; whereas one 10g cube of dark chocolate may contain as much as 20% of the daily lead oral limit. Moreover chocolate may not be the only source of lead in their nutrition. For adults there is almost no risk of exceeding daily limits for trace metals ingestion because their digestive absorption of metals is very poor. [Copyright &y& Elsevier]

Highlights: [•] Water-soluble protein fraction of Brazil nuts contains Cu-containing proteins. [•] A Cu-containing peptide in tryptic digest was identified by MALDI MS using modified isotope pattern. [•] A tentative formula, [M+Cu(I)]+, was proposed for the Cu-containing peptide based on MALDI MS data. [Copyright &y& Elsevier]

Highlights: [•] We report the uranium concentration in 951 drinking water samples from Kosovo. [•] The water samples were analyzed with inductively coupled plasma mass spectrometry. [•] 2.6% Of analyzed water samples exceeded WHO drinking water guidelines of 30μgL−1. [•] 44% Of the water samples exceed the recommended concentration for babies (2μgL−1). [•] Our data provide valuable information for the population and authorities of Kosovo. [ABSTRACT FROM AUTHOR]

Abstract: Illicit drugs manufactured from clandestine laboratories are often impure due to poor laboratory conditions, variations in synthesis and impure starting materials extracted either from common household products or pharmaceutical grade chemicals. Inductively coupled plasma mass spectrometry (ICPMS) can be utilised as a multi-element analytical tool to elicit the inorganic impurities which may be present in such samples, however the interpretation of the resultant data can be problematic and complex. This is particularly true when dealing with seized samples of unknown provenance. In this work, we have presented and interpreted inorganic profiles as a means to explore within and between batch variations in known provenance samples produced via two different popular synthetic routes. Samples were prepared from essential chemicals recovered from household materials and pharmaceutical medication available in the UK and extracted using different solvents. The presence or absence of elements in the final synthesised products could be linked to the synthesis route, salting out method and potentially the solvent used in the precursor extraction process. [Copyright &y& Elsevier]

Samples from 33 individual eruptions of Bezymianny volcano between 1956 and 2010 provide an opportunity to study in detail the temporal evolution of an arc volcano. Major element and ICP-MS trace element analyses show that the eruptive products shifted progressively from relatively silicic magma in 1956 (~60.4% SiO2) to more mafic compositions (e.g. 56.8% SiO2 in 2010). Amphibole compositions changed concurrently from low-Al2O3 to high-Al2O3. Whole rock element-element variation diagrams show tight compositional arrays, some with a distinct kink in the late 1970s, which cannot be reproduced by fractionation of a single magma along a liquid line of descent. Amphibole thermobarometry indicates amphibole crystallization in two separate reservoirs, one between 200 and 300MPa, and another between 500 and 750MPa. Liquid compositions calculated from the amphibole analyses show that liquids stored in each reservoir become increasingly mafic from 1956 to 2010, suggesting that each reservoir received magma inputs from more mafic sources throughout the eruptive cycle. End member mixing analysis of the dataset allows calculation of three end member compositions that can be combined in varying proportions to reproduce major and trace element whole rock compositions. The end-member mixing proportions vary systematically between 1956 and 2010, with maxima for end-members A, B and C during 1956, 1977, and 2010, respectively. Major element compositions of phenocrysts, combined with published trace element partition coefficients, show that each end member may have evolved from a common parental magma by fractionation of three different mineral assemblages, possibly due to different pressures of crystallization and volatile contents. The petrologic data are consistent with three magma reservoirs at different depths. Magmas from the shallowest reservoir erupted first, with increasing proportions of deeper reservoirs over time. Past studies have demonstrated similarities in eruptive style between Bezymianny and both Mount St. Helens and Soufrière Hills volcanoes. Contrasting time series data show that the magma plumbing systems of Mount St. Helens and Bezymianny have little in common, while Soufrière Hills may be a better analog. Similar eruptive styles at the surface do not necessarily reflect similar systems of magma supply and evolution at depth. [ABSTRACT FROM AUTHOR]

Abstract: Otolith microchemistry is a powerful tool for fisheries biology, but many applications stretch the limits of analytical techniques. Sources of measurement error were evaluated with a methodological comparison of solution and laser ablation inductively coupled plasma mass spectrometry at two laboratories, using otoliths and certified reference materials NIES-22 and FEBS-1. The intercalibration exercise was effective for Na, Ca, Zn, Cu, Sr, Ba, and Pb. Measurements of Sr were most robust, i.e. sensitivity, accuracy, and precision were least affected by laboratory, technique or sample type. Calcium and Ba measurements varied more between laboratories than between techniques. Lead and Cu measurements were more dependable across laboratory and technique while Zn measurements were more sensitive to these effects. Because the measurement of otolith elements may vary with methodology, it is imperative to consider the sensitivity, accuracy and precision for each application as the suite of elements of interest may differ. The development of reference materials has been the first step in standardization of the procedures, but there is a need for wider ranging calibration and comparison studies. [Copyright &y& Elsevier]

Abstract: This study is one of several baseline studies that will provide basic and reliable information about the content of undesirable substances in important species of fish caught in Norwegian waters. Concentrations of metals in the muscle and liver of more than 800 Northeast Arctic cod caught at 32 sites in the Barents Sea are reported. The highest concentration of both mercury in the muscle and cadmium in the liver was found in cod caught in the western part of the Barents Sea, while the highest concentration of total arsenic was found in cod from the eastern part. The arsenic concentrations varied greatly among individual fish, ranging from 0.3 to 170mgkg−1 wet weight in the muscle. Such high levels of total arsenic have never previously been reported in any fish, and the primary factor for these high concentrations is likely to be the shrimp in the cod diet. [Copyright &y& Elsevier]

Abstract: Concentrations of twelve elements (Mg, Al, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd) were determined in six herbal supplements, Korean Panax Ginseng (Panax ginseng), Golden Seal (Hydrastis canadensis), Ginger Root (Zingiber officinale), St. John''s Wort (Hypericum perforatum), Green Tea (Camellia sinensis) and Valerian Root (Valeriana officinalis), by both laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) and conventional closed-vessel digestion solution nebulization-ICPMS (SN-ICPMS). For LA-ICPMS, powder from supplement capsules and leaf reference materials were pressed into pellets, the later being used for calibration and quality assurance. Laser ablation was performed using line scans with a scan rate of 30μmmin−1, a frequency of 20Hz and a spot size of 100μm; 13C served as the internal standard. For LA it was found that low resolution (m/Δm≈400) yielded good recoveries for the reference materials and results comparable to SN-ICPMS for most elements, except for Ca, which was better determined in medium resolution (m/Δm≈4000). Overall, this study shows that LA-ICPMS can serve as an alternative way for determining the concentration of elements in herbal supplements in a rapid and pragmatic fashion. [Copyright &y& Elsevier]

Abstract: Speleothem proxy records, coupled with U–Th chronologies, are widely used in studies of palaeoclimate, landscape and faunal evolution. The prospect of extending such studies beyond ∼500 ka has fuelled considerable interest in the U–Pb dating method. While theoretical mechanisms for the transport and incorporation of both U and Pb in speleothem calcite remains a matter of debate, it is clear that natural samples span a broad spectrum of compositional variation, and likely contain Pb components with multiple origins and/or transport pathways. Based upon these observations, optimal methods for sample selection are proposed and a variety of techniques for age estimation are explored. Laser ablation ICPMS and autoradiography are ideal rapid screening methods for reconnaissance studies. Common Pb isotopic variability is a key parameter in the choice of analytical strategy for age determination. In large U–Pb studies where invariant common Pb can be established, common Pb corrected ages can be produced for individual sample aliquots promoting rapid throughput and permitting the establishment of detailed age-depth models. Even with these technologies, however, age resolution becomes an issue beyond a few million years, at which time alternative strategies for developing internal speleothem chronologies, such as lamina counting, must be considered in unison with U–Pb dating. [Copyright &y& Elsevier]

Abstract: We have developed a new method for the quantification of 11 major and minor elements (Na, Mg, Al, P, S, K, Ca, Cr, Mn, Fe, and Ni) in chondritic meteorites by ICPMS using external calibration with a matrix-matched standard prepared from the Allende Standard Reference Meteorite. We have demonstrated the method''s accuracy and assessed three different measures of precision by performing replicate dissolutions and analyses of 0.10-g samples of a homogenized samples of the CM2 meteorite Murchison and compared our results to literature values. We subsequently applied this method to the analysis of a set of four chondritic meteorites possessing a relatively wide range of chondritic compositions with results in accord with previously published values. Because our method is designed to use the same instrumentation and can use samples and standards prepared according to methods previously validated for the determination of a comprehensive suite of minor, trace, moderately and highly volatile trace elements (i.e., Li, Sc, Ti, V, Mn, Co, Cu, Zn, Ga, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Ru, Pd, Ag, Cd, In, Sn, Sb, Te, Cs, Ba, all 14 naturally occurring lanthanoids, Hf, W, Re, Ir, Pt, Tl, Bi, Th, and U) it complements these methods and allows a single laboratory to determine the concentrations of 60 elements in semimicroscopic amounts of chondritic material. [Copyright &y& Elsevier]

Abstract: The characteristics of an electrodynamic ion funnel as an alternative ion optics element for inductively coupled plasma mass spectrometry (ICPMS) were investigated in this work. Therefore the ion lens of a conventional ICPMS system has been removed and a custom made ion funnel was installed instead. The effects of the radiofrequency-amplitude and frequency and the axial funnel potential on the ion transmission have been investigated for different configurations. Under optimum conditions the ion current was in average 10-fold lower than with the un-modified instrument, while CeO+/Ce+ ratios increased ten-fold. Nonetheless, confinement of atomic ions from the ICP inside the ion funnel could be achieved by optimizing radiofrequency and DC potentials at the funnel electrodes as indicated by an increase in the ion signal intensities relative to the field-free case. With the ion funnel being partially enclosed, gases, such as N2 and H2, could be introduced which can reduce the abundance of Ar+ and Ar-based polyatomic ions by one (H2) to three (N2) orders of magnitude. Based on these experiments, however H2 would be more favorable since it did not affect the transmission of low m/z analyte ions to a great extent. [Copyright &y& Elsevier]

Abstract: Monocrystalline gem-quality diamonds from Akwatia, Ghana and De Beers Pool, South Africa were analyzed for their trace element content using an ultra-sensitive ‘off-line’ LA-ICP-MS method. Concentrations of 27 elements analyzed range from ppt to ppm level but mostly are below the LOQ. CeN/EuN (1–6; N=chondrite normalized) and CeN/TiN (0.6 to 12) indicate mildly elevated LREEN/MREEN and variable LREEN/TiN. One diamond from Ghana is distinct (G103) by having a much steeper LREEN/MREEN slope than the other samples and overall matches the trace element pattern of low-Mg carbonatitic melt inclusions in fibrous diamonds from Kankan, Guinea (Weiss et al., 2009). Syngenetic garnet inclusions indicate that the diamond growth medium must have been highly enriched in LREE, with CeN/EuN and CeN/TiN from 9 to 370 and 10 to 3400, respectively. This extreme discrepancy in trace element ratios between these gem diamonds and inclusion-based melt compositions is inconsistent with the commonly made interpretation that trace impurities in gem diamond represent trapped inclusions of the diamond forming fluid/melt. Mixtures of submicroscopic inclusions of common peridotitic and metasomatic phases in equilibrium with a basaltic melt mimic the relative Ce, Eu and Ti abundances of the studied diamonds. But models are dominated by orthopyroxene and hence, do not correspond to modal relationships expected for peridotitic sources. The models also require at least 0.5% of the sample volume be occupied by inclusions, which would affect diamond transparency. Incorporation of exotic minerals that are normally rare or as yet undiscovered in peridotite (e.g. crichtonite group minerals and REE phosphates) could significantly lower the required inclusion abundance to an extent that preserves the transparent nature of gem diamonds. The principal finding of our study is that, with one exception, the trace element patterns of these gem diamonds do not yield a faithful representation of the diamond growth medium and hence caution is required when extrapolating gem quality diamond trace element measurements into “fluid” compositions. [Copyright &y& Elsevier]

Abstract: In compliance with the European law (EC No. 510/2006), geographical indications and designations of origin for agricultural products and foodstuffs must be protected against mislabelling. This is particularly important for PDO hard cheeses, as Parmigiano Reggiano, that can cost up to the double of the no-PDO competitors. This paper presents two statistical models, based on isotopic and elemental composition, able to trace the origin of cheese also in grated and shredded forms, for which it is not possible to check the logo fire-marked on the rind. One model is able to predict the origin of seven types of European hard cheeses (in a validation step, 236 samples out of 240 are correctly recognised) and the other specifically to discriminate the PDO Parmigiano Reggiano cheese from 9 European and 2 extra-European imitators (260 out of 264 correct classifications). Both models are based on Random Forests. The most significant variables for cheese traceability common in both models are δ 13C, δ 2H, δ 15N, δ 34S and Sr, Cu, Mo, Re, Na, U, Bi, Ni, Fe, Mn, Ga, Se, and Li. These variables are linked not only to geography, but also to cow diet and cheese making processes. [Copyright &y& Elsevier]

Abstract: In this work we discuss about the method development, applicability and limitations of an asymmetric flow field flow fractionation (A4F) system in combination with a multi-detector setup consisting of UV/vis, light scattering, and inductively coupled plasma mass spectrometry (ICPMS). The overall aim was to obtain a size dependent-, element specific-, and quantitative method appropriate for the characterization of metallic engineered nanoparticle (ENP) dispersions. Thus, systematic investigations of crucial method parameters were performed by employing well characterized Au nanoparticles (Au-NPs) as a defined model system. For good separation performance, the A4F flow-, membrane-, and carrier conditions were optimized. To obtain reliable size information, the use of laser light scattering based detectors was evaluated, where an online dynamic light scattering (DLS) detector showed good results for the investigated Au-NP up to a size of 80nm in hydrodynamic diameter. To adapt large sensitivity differences of the various detectors, as well as to guarantee long term stability and minimum contamination of the mass spectrometer a split-flow concept for coupling ICPMS was evaluated. To test for reliable quantification, the ICPMS signal response of ionic Au standards was compared to that of Au-NP. Using proper stabilization with surfactants, no difference for concentrations of 1–50μg AuL−1 in the size range from 5 to 80nm for citrate stabilized dispersions was observed. However, studies using different A4F channel membranes showed unspecific particle–membrane interaction resulting in retention time shifts and unspecific loss of nanoparticles, depending on the Au-NP system as well as membrane batch and type. Thus, reliable quantification and discrimination of ionic and particular species was performed using ICPMS in combination with ultracentrifugation instead of direct quantification with the A4F multi-detector setup. Figures of merit were obtained, by comparing the results from the multi detector approach outlined above, with results from batch-DLS and transmission electron microscopy (TEM). Furthermore, validation performed with certified NIST Au-NP showed excellent agreement. The developed methods show potential for characterization of other commonly used and important metallic engineered nanoparticles. [Copyright &y& Elsevier]

Abstract: Owing to recent studies which showed that Se supplementation in the diet can reduce the risk of several forms of cancer, efforts have been directed to identify anticarcinogenic activity in Se compounds from natural sources with the objective of using those as food supplements. As a part of a continuing research project directed at identifying Se-containing species in food stuffs, the distribution of selenium-containing proteins in water-soluble protein fraction of seeds of Bertholletia excelsa H.B.K., which typically have a high Se content, was studied under non-denaturing conditions and the effectiveness of protein fractional precipitation by ammonium sulfate was investigated with the objectives to preconcentrate the protein(s) of interest and to reduce the matrix complexity. By SEC–ICPMS, Se-containing proteins (selenoproteome with some additional proteins) were found demonstrating the usefulness of ICPMS as an “on-line assay” in sub-proteomics investigations. Fractions with Se-containing proteins, collected from SEC, were tryptically digested and tryptic digests were analyzed by MALDI-TOF-reflectron MS and capLC–ESI-QTOF-MS. Isotope patterns which are different from the typical isotope patterns of peptides containing C, H, O, N and S were used to identify selenium-containing peptides in the digests. Observed isotope patterns were slightly different from the predicted isotope patterns and partial deamidation of selenium-containing peptides is suggested to explain the modified isotope pattern. To our knowledge, this is the first report of the effect of partial deamidation of selenium-containing peptides on the observed selenium isotope pattern, although the evidence is indirect. According to the SEC–ICPMS study, Se-containing proteins in water-soluble protein fraction of Bertholletia excelsa H.B.K. seeds can be divided into two main sub-groups-high molecular weight Se-containing proteins and low molecular weight Se-containing proteins. LC–ESI-MS and MS/MS analysis of tryptic digest of low-molecular weight Se-containing proteins identified 2S albumins, which are rich in methionines; therefore, with a high probability of non-specific selenomethionine incorporation—as the proteins present in that fraction. [Copyright &y& Elsevier]

Abstract: The levels of 20 essential or toxic trace elements in 159 fish, other seafood and seafood products on the French coastal market collected between January and April 2005 were measured by ICP-MS. The concentration ranges (mg/kg of fresh mass) for the elements determined were compared with previous studies. The contents of Co, Cu, Fe, Li, Mn, Se, Zn and Pb found in fish are close to or often lower than previous studies. For other seafood, comparison is difficult due to the lack of data on a more global scale. However, it should be noted that the contents of Ag were found considerably higher in this study. [Copyright &y& Elsevier]

Abstract: A procedure for the extraction and determination of methyl mercury and mercury (II) in fish muscle tissues and sediment samples is presented. The procedure involves extraction with 5% (v/v) 2-mercaptoethanol, separation and determination of mercury species by HPLC-ICPMS using a Perkin-Elmer 3μm C8 (33mm×3mm) column and a mobile phase 3 containing 0.5% (v/v) 2-mercaptoethanol and 5% (v/v) CH3OH (pH 5.5) at a flow rate 1.5mlmin−1 and a temperature of 25°C. Calibration curves for methyl mercury (I) and mercury (II) standards were linear in the range of 0–100μgl−1 (r 2 =0.9990 and r 2 =0.9995 respectively). The lowest measurable mercury was 0.4μgl−1 which corresponds to 0.01μgg−1 in fish tissues and sediments. Methyl mercury concentrations measured in biological certified reference materials, NRCC DORM – 2 Dogfish muscle (4.4±0.8μgg−1), NRCC Dolt – 3 Dogfish liver (1.55±0.09μgg−1), NIST RM 50 Albacore Tuna (0.89±0.08μgg−1) and IRMM IMEP-20 Tuna fish (3.6±0.6μgg−1) were in agreement with the certified value (4.47±0.32μgg−1, 1.59±0.12μgg−1, 0.87±0.03μgg−1, 4.24±0.27μgg−1 respectively). For the sediment reference material ERM CC 580, a methyl mercury concentration of 0.070±0.002μgg−1 was measured which corresponds to an extraction efficiency of 92±3% of certified values (0.076±0.04μgg−1) but within the range of published values (0.040–0.084μgg−1; mean±s.d.: 0.073±0.05μgg−1, n =40) for this material. The extraction procedure for the fish tissues was also compared against an enzymatic extraction using Protease type XIV that has been previously published and similar results were obtained. The use of HPLC-HGAAS with a Phenomenox 5μm Luna C18 (250mm×4.6mm) column and a mobile phase containing 0.06moll−1 ammonium acetate (Merck Pty Limited, Australia) in 5% (v/v) methanol and 0.1% (w/v) l-cysteine at 25°C was evaluated as a complementary alternative to HPLC-ICPMS for the measurement of mercury species in fish tissues. The lowest measurable mercury concentration was 2μgl−1 and this corresponds to 0.1μgg−1 in fish tissues. Analysis of enzymatic extracts analysed by HPLC-HGAAS and HPLC-ICPMS gave equivalent results. [Copyright &y& Elsevier]

Abstract: Uptake of gaseous elemental mercury (Hg0 (g)) by three plant species and two soil types was measured using mercury vapor enriched in the 198 isotope (198Hg0 (g)). The plant species and soil types were: White Ash (Fraxinus Americana; WA); White Spruce (Picea Glauca; WS); Kentucky Bluegrass (Poa Partensis; KYBG); Plano Silt Loam (4% organic matter; PSL); and Plainfield Sand/Sparta Loamy Sand (1.25–1.5% organic matter: PS). The plants and soils were exposed to isotopically enriched Hg0 (g) in a 19 m3 controlled environment room for 7 days under optimal plant growth conditions (20 °C, 140 Wm−2 between 300 nm and 700 nm; 70% RH) and atmospherically relevant Hg0 (g) concentrations. Mercury was recovered from the samples using acidic digestions and surface leaches, and then analyzed for enrichments in 198Hg by ICPMS. The method was sensitivity enough that statistically significant enrichments in 198Hg were measured in the plant foliage at the end of Day 1. Whole leaf digestions and surface-selective leaches revealed that accumulative uptake was predominantly to the interior of the leaf under the conditions studied. Uptake fluxes for WA increased between the first and third days and remained constant thereafter (WA; Day 1 = 7 ± 2 × 10−5 ng m−2 s−1; Days 3–7 = 1.3 ± 0.1 × 10−4 ng m−2 s−1; where m2 refers to one sided leaf area). KYBG demonstrated similar behavior although no Day 3 measurement was available (Day 1 = 7.5 ± 0.5 × 10−5 ng m−2 s−1; Day 7 = 1.2 ± 0.1 × 10−4 ng m−2 s−1). Fluxes to White Spruce were lower, with little difference between Days 1 and 3 followed by a decrease at Day 7 (WS; Days 1–3 = 5 ± 2 × 10−5 ng m−2 s−1; Day 7 = 2.4 ± 0.2 × 10−5 ng m−2 s−1). Uptake of Hg to soils was below the method detection limit for those media (PSL = 3 × 10−2 ng m−2 s−1; PS = 3 × 10−3 ng m−2 s−1) over the 7 day study period. Foliar resistances calculated for each species compared well to previous studies. [Copyright &y& Elsevier]

Abstract: We present highly sensitive, reliable methods for the determination of platinum originating from carboplatin in canine sebum and cerumen. The methods are based on the measurement of platinum by inductively coupled plasma mass spectrometry and allow quantification of 0.15pg platinum per cm2 body surface in canine sebum and of 7.50pg platinum per sampled ear canal. The sample pretreatment procedure involved extraction of wipe samples followed by dilution with appropriate diluents. The performance of the methods, in terms of accuracy and precision, fulfilled the most recent FDA guidelines for bioanalytical method validation. Validated ranges of quantification were 15.0–1.00×104 ngL−1 for platinum in canine sebum extraction solution (corresponding to 15.0pg per wipe sample or 0.15pgcm−2) and 7.50–1.00×104 ngL−1 for platinum in canine cerumen extraction solution (corresponding to 7.50pg per sampled external acoustic meatus). Canine matrices may not always be obtained in sufficient quantities. Therefore, we also confirmed the legitimacy of the application of human matrix samples for the preparation of calibration standards and quality control samples as alternatives, to be used in future clinical studies. The assays are used to support human biomonitoring studies and pharmacokinetic oncology studies in pet dogs treated with carboplatin. [ABSTRACT FROM AUTHOR]

Abstract: A novel flow injection ion chromatograph (FI-IC) system has been developed to fully automate pretreatment procedures for multi-elemental analysis of trace metals in seawater by inductively coupled plasma mass spectrometer (ICPMS). By combining 10-port, 2 position and 3-way valves in the FI-IC manifold, the system effectively increase sample throughput by simultaneously processing three seawater samples online for: sample loading, injection, buffering, preconcentration, matrix removal, metal elution, and sample collection. Forty-two seawater samples can be continuously processed without any manual handing. Each sample pretreatment takes about 10min by consuming 25mL of seawater and producing 5mL of processed concentrated samples for multi-elemental offline analysis by ICPMS. The offline analysis improve analytical precision and significantly increase total numbers of isotopes determined by ICPMS, which include the metals Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti, V, and Zn. The blank value and detection limits of trace metals using the system with ICPMS analysis all range from 0.1 to 10 parts per trillion (ppt), except Al, Fe, and Zn. The accuracy of the pretreatment system was validated by measuring open-ocean and coastal reference seawater, NASS-5 and CASS-4. Using the system with ICPMS analysis, we have obtained reliable trace metal concentrations in the water columns of the South China Sea. Possessing the features of full automation, high throughput, low blank, and low reagent volume used, the system automates and simplifies rigorous and complicated pretreatment procedures for multi-elemental analysis of trace metals in seawater and effectively enhances analytical capacity for trace metal analysis in environmental and seawater samples. [ABSTRACT FROM AUTHOR]