Inductively Coupled Plasma Mass Spectrometry Technique Research Articles

The Combined ICP-MS, ESEM-EDX, and HAADF-STEM-EDX Approach for the Assessment of Metal Sub-Micro- and Nanoparticles in Wheat Grain.

Metal sub-microparticles (SMPs) and nanoparticles (NPs) presence in food is attributable to increasing pollution from the environment in raw materials and finished products. In the present study, a multifaceted analytical strategy based on Environmental Scanning Electron Microscopy and High-Angle Annular Dark-Field-Scanning Transmission Electron Microscopy coupled with Energy-Dispersive X-ray Spectroscopy (ESEM-EDX, HAADF-STEM-EDX) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was proposed for the detection and characterization of metal and metal-containing SMPs and NPs in durum wheat samples, covering a size measurement range from 1 nm to multiple µm. ESEM-EDX and ICP-MS techniques were applied for the assessment of SMP and NP contamination on the surface of wheat grains collected from seven geographical areas characterized by different natural and anthropic conditions, namely Italy, the USA, Australia, Slovakia, Mexico, Austria, and Russia. ICP-MS showed significant differences among the mean concentration levels of metals, with the USA and Italy having the highest level. ESEM-EDX analysis confirmed ICP-MS concentration measurements and measured the highest presence of particles < 0.8 µm in size in samples from Italy, followed by the USA. Less marked differences were observed when particles < 0.15 µm were considered. HAADF-STEM-EDX was applied to a selected number of samples for a preliminary assessment of internal contamination by metal SMPs and NPs, and to expand the measurable particle size range. The multifaceted approach provided similar results for Fe-containing SMPs and NPs. ICP-MS and ESEM-EDX also highlighted the presence of a significant abundance of Ti- and Al-containing particles, while for STEM-EDX, sample preparation artifacts complicated the interpretation. Finally, HAADF-STEM-EDX results provided relevant information about particles in the low nm range, since, by applying this technique, no particles smaller than 50 nm were observed in accordance with ESEM-EDX.

Development and validation of ICPMS methods for simultaneous determination of elemental impurities in topical cream containing ximenynic acid

BackgroundThese days, the presence of simple impurities in pharmaceuticals is a major cause for worry. This is because some contaminants are dangerous on their own, and even small impurities can make a drug less stable and shorten its shelf life. The goal of this study was to see if creams with ximenynic acid could be tested with inductively coupled plasma-mass spectrometry to find out how much arsenic, mercury, lead, cadmium, vanadium, cobalt, and nickel were in them. The best way to do things would be one that was quick, accurate, sensitive, and very productive (ICP-MS). The method included both inductively coupled plasma mass spectrometry (ICP-MS) and microwave digestion.ResultsSeven of the seven linearity correlation coefficient (‘R’) value were more than 0.99. LOD values were calculated using 33% of the 0.25 J threshold. Six LOQ responses (0.25 J level) were taken after considerable discussion. Calculated and reported %RSD for six LOQ copies. All elemental impurities Vanadium (V), Cobalt (Co), Nickel (Ni), Arsenic (As), Cadmium (Cd), Mercury (Hg), and Lead (Pb) were recovered between 83.33% and 115.97%, within acceptability limits. RSD% for procedure precision and intermediate precision data never exceeded 5%. The available evidence shows that the ICP-MS technique is a good way to measure these components.ConclusionThe statistical analysis showed that the developed ICP-MS method for measuring elements in Topical Cream with Ximenynic Acid is selective and accurate. Since this ICPMS method is good at estimating several elements simultaneously, it could be used to check for elemental contaminants in the formulation.

Measuring uranium concentration in Um Qasr district, southern Iraq, in two different ways

The current study uses ICP-MS (inductively coupled plasma mass spectrometry) and SSNTDs (solid-state nuclear track detectors) to measure uranium concentrations in 12 surface soil samples from selected locations in Um Qasr in the Southern Basrah governorate. In the ICP-MS technique, uranium concentrations ranged from 0.6 to 2.2 ppm, with an average value of 1.3 ppm. In the SSNTDs technique, uranium concentrations ranged from 1.4 ± 0.3 ppm to 1.6 ± 0.2 ppm, with an average value of 1.5 ± 0.2 ppm. The results obtained from the soil samples were within the permissible limits recommended by the UNSCEAR Committee of 11.7 ppm.

Chemometric classification and discrimination of herbal dietary supplements based on ICP-MS elemental profiling

This study presents the determination of elemental profiling of representative dietary herbal supplements which were purchased on the Croatian market in the forms of capsules, powders, jams or liquids. Using inductively coupled plasma mass spectrometry (ICP-MS), twenty-four elements in eighty-seven different samples were determined. Electrothermal atomic absorption with hydride generation technique (HG-ETAAS) applied for the selenium determination in all samples gave the similar results as ICP-MS technique. Elemental profiling resulted with determination of major constituents Na, Mg, Ka and Ca with mean concentration values of 2900, 2700, 9200, and 16,600 mg kg−1, respectively. Elements of middle concentration range were: B, Al, Mn, Fe, Zn and Sr (31.8–1050 mg kg−1). Trace and ultra-trace levels comprise of Se, V, Cr, Co, Ni, Cu, As, Mo, Cd, Sb, Hg, Tl and Pb (21.7–11,300 µg kg−1). Using PLS-DA statistical analysis, the elements Se, Na, Fe, Co, Tl, and Zn, were established as the marker elements with the greatest discriminating power between supplement samples. Multivariate PCA analysis resulted with the successful discrimination of Se and Zn enriched supplements. Hierarchical cluster analysis (HCA) enhanced the recognition of similarities in sub-clusters of samples. Minor discrepancies in trace and ultra-trace elemental profiles revealed Hg, As, Cd, Pb, Cr and Co as the key elements for discrimination between two groups of Ayurvedic and spirulina-based supplements. The HCA method also allowed visualization of the exceptional elemental profile of several mixed-herb supplements. There were distinctive features of herbal dietary supplements with peculiar influences of botanical, environmental and/or production conditions on their elemental profile.

The Elemental Fingerprints of Different Types of Whisky as Determined by ICP-OES and ICP-MS Techniques in Relation to Their Type, Age, and Origin.

A total of 170 samples of whisky from 11 countries were analysed in terms of their elemental profiles. The levels of 31 elements were determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS): Ag, Al, B, Ba, Be, Bi, Cd, Co, Cr, Cu, Li, Mn, Mo, Ni, Pb, Sb, Sn, Sr, Te, Tl, U, and V, Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) Ca, Fe, K, Mg, P, S, Ti, and Zn and Cold Vapor-Atomic Absorption (CV-AAS): Hg techniques in those alcoholic samples. A comparative analysis of elemental profiles was made on the basis of the content of chosen elements with regard to selected parameters: country of origin, type of whisky (single malt and blended) and age of products. One of the elements which clearly distinguishes single malt and blended types of whisky is copper. Single malt Scotch whisky had a uniform concentration of copper, which is significantly higher for all malt whisky samples when compared with the blended type. Analysis of samples from the USA (n = 26) and Ireland (n = 15) clearly revealed that the objects represented by the same product but originating from independent bottles (e.g., JB, JDG, BUS brands) show common elemental profiles. On the other hand, comparative analysis of Scotch whisky with respect to aging time revealed that the longer the alcohol was aged, (i.e., the longer it stayed in the barrel), the higher the content of Cu and Mn that was recorded.

Trace elements distribution in stream sediments of an abandoned U mining site in the Eastern Carpathians, Romania, with particular focus on REEs

Trace elements distribution, including rare earth elements (REEs), in stream sediments of an abandoned U mining site in the Eastern Carpathians, Romania, were of high concern of interest in the present work. A total number of 40 riverbed sediments samples collected from the Bistricioara River and local tributaries (Primatar, Bradul, Prisacani, Barasau, Grintiesul Mare and Valea Seaca) were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and energy dispersive X-ray fluorescence spectrometry (XRF). All REEs including La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu were identified and quantified in the present work using ICP-MS technique. For other 24 elements (Ti, V, Cr, Co, Zn, Li, Be, Rb, Sr, Y, Sc, Zr, Nb, Sb, Ba, Ta, W, Pb, U, Ni, Cu, Mo, As, Th) similar information was obtained either by ICP-MS or XRF techniques. The impact and the relevance of the obtained data base might be significant at a local scale of about 50 km2.Enrichments of some trace elements of interest in comparison to the upper continental crust allowed discrimination between various mineralization processes specific for the investigated areas. Uranium mineralization and Paltin-type (Pb, Zn) mineralization seems to be specific for the NW area of the investigated region. Negative anomaly characteristic for the upper crustal rocks was identified for Eu and Ce elements. Evidences were obtained also for the existence of ultramafic rocks (Ni, Cr, Co and V) in the investigated riverbed sediments. The observation was also confirmed by the binary plots analysis of Th/Cr vs. Th/Co and Cr/V vs. Y/Ni pairs. From the investigated tributaries to Bistricioara River, Barasau seems to exert the highest influence on the abundances of REEss in the entire area. Most probably some chemical parameters such as the pH of the water streams influence leaching and depletions of some chemical constituents in various minerals specific for the region.The existence of magnetite, garnets, pyrite and sillimanite minerals was confirmed by SEM-EDAX and XRF analysis, as well by optical microscopy. Principal Component Analysis runs confirmed the association of some chemical elements in the riverbed sediments in close connection with the minerals from which they originate.The present work reports for the first time upon the authors knowledge clear scientific evidence and chemical information concerning the geology and geochemistry, i.e. transition metals, high field strength elements, alkali and alkaline earth elements, rare earth elements (REEs) and others, in stream sediments crossing the Tulghes-Grinties mining area (Eastern Carpathians, Romania). For the analysed REEs this is the first study reporting consistent information on the concentrations of the entire array of both light REEs (six elements) and heavy REEs (ten elements) in Bistricioara Basin stream sediments. Relevant scientific data related to geochemical characteristics of ultramafic rocks existent in the investigated area were also generated. Moreover, data reported in the present work might be considered as a reference geochemical database relevant for the investigated area, which can be used as a trustworthy input for a systematic national geochemical atlas.

Titanium dioxide nanoparticles in food: comparison of detection by triple-quadrupole and high-resolution ICP-MS in single-particle mode

We used triple-quadrupole and high-resolution inductively coupled plasma-mass spectrometry (ICP-MS) in single-particle mode to characterize the food additive E171 (titanium dioxide, TiO2) in chewing gum, chocolate candy, and cake decoration in the same sample extracts. Then, we spiked TiO2 particles (with similar characteristics as E171) to milk as an example of a calcium-rich matrix. The obtained particle size distributions with both techniques were highly similar in terms of shape and median and mean diameters. Median diameters were in the range of 123 to 209 nm and mean diameters from 146 to 223 nm. In addition, they were in agreement with results obtained by scanning electron microscopy and asymmetric flow field-flow fractionation coupled to multi-angle light scattering and ICP-MS. Repeatable determination of number-based particle size distributions was possible with both ICP-MS techniques even in a calcium-rich matrix showing that both instruments were similarly efficient in resolving the Ca interferences. The combination of spICP-MS with microscopy and TiO2 recovery allowed validating the methods and identifying the presence of aggregated/agglomerated particles in one sample. For the TiO2 powder and the two remaining food products, recoveries were higher than 60%. Both instruments are fit for purpose even if the analyses were performed with differences in detector mode, dwell times, and calculation tools. This shows that both techniques may be used as long as operating conditions are optimized and applicability range is defined.

Detection of Pb, Ba, and Sb in Cadaveric Maggots and Pupae by ICP‐MS*

The concentrations of lead (Pb), barium (Ba), and antimony (Sb), characteristic of GSR, were determined in soil sediments and immature (larvae) of cadaveric flies of the family Calliphoridae, by inductively coupled plasma mass spectrometry (ICP-MS). This research refers to a case study from two real crime scenes in which the corpses were in an advanced state of decomposition. In case 1, the victim had holes similar to gunshot wounds, and in case 2, there was no evidence of perforations in the corpse. Soil sediment collection was performed at three different points of the terrain, at a minimum distance of 10m from the corpse, for cases 1 and 2. In relation to the collection of immatures, larvae were collected in regions of the mouth, nose, and orifices similar to the entry of firearms projectile into the body, for case 1, and collection of larvae and pupae, located on the body and underneath it, for case 2. It was possible to detect and quantify the three elements of interest (Pb, Ba, and Sb) by ICP-MS in both sediment and cadaveric larvae. Concentrations of 4.44, 8.74, and 0.08μg/g were obtained for Pb, Ba, and Sb, respectively, in the soil for case 1. For the case 2, the concentrations in Pb, Ba, and Sb were from 16.34 to 26.02μg/g; from 32.64 to 57.97μg/g and from 0.042 to 0.30μg/g, respectively. In the larvae, Pb, Ba, and Sb were quantified in cases 1 and 2 with a concentration of 6.28 and 1.78μg/g for Pb, 1.49 and 2.94μg/g for Ba, 0.50μg/g and <LD for Sb, respectively. These new results present the detection of characteristic elements of GSR in cadaveric larvae in humans in a real crime scene, besides highlighting the importance of the study of immature flies, using the ICP-MS technique in forensic analysis.

Determination of trace elements in Sergio mirim: an evaluation of sample preparation methods and detection techniques.

In this work, some trace elements (As, Cd, Cr, Cu, and Pb) were determined for the first time in the crustacean Sergio mirim (Decapoda: Thalassinidea: Callianassidae) from Southern Coast (Rio Grande, RS) of Brazil. The trace element determination was carried out by graphite furnace atomic absorption spectrometry (GF AAS) and inductively coupled plasma mass spectrometry (ICP-MS). Different microwave radiation-based sample digestion methods were evaluated. The analyte concentration ranged from 1.45 to 3.70μgg-1 for As, 0.615 to 0.942μgg-1 for Cd, 0.884 to 7.20μgg-1 for Cr, 122 to 275μgg-1 for Cu, and 0.390 to 0.916μgg-1 for Pb. The limits of quantification for As, Cd, Cr, Cu, and Pb were 0.12, 0.01, 0.16, 0.92, and 0.06μgg-1, respectively. The accuracy was evaluated by results comparison between GF AAS and ICP-MS techniques, as well as by analysis of certified reference materials of fish muscle and oyster tissue, with agreement from 92 to 108%. The feasibility of using Sergio mirim as a promising environmental bioindicator candidate was evaluated, since that it is an abundant organism in the studied area (South cost of Brazil) as well as in other places around the world.

Spatial and temporal variability of metal(loid)s concentration as well as simultaneous determination of five arsenic and antimony species using HPLC-ICP-MS technique in the study of water and bottom sediments of the shallow, lowland, dam reservoir in Poland

The optimization of new methodology for simultaneous determination of arsenic [As(III), As(V)] and antimony [Sb(III), Sb(V), SbMe3] species using high-performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) in water and bottom sediment samples collected from the dam Kozłowa Góra Reservoir (Poland) was studied. Samples were collected monthly from May to September 2018 in four-point (water) and fifth-point (sediment) transects. The contents of Mn, Co, Ni, Cu, Zn, As, Cr, Rb, Sr, Cd, Sb, Ba, Tl, Pb, and Sb were studied in water and bottom sediments using ICP-MS techniques. Additionally, arsenic and antimony fractions were determined in sediments with the BCR method. Pollution Load Index (PLI), Geoaccumulation Index (Igeo), LAWA classification, and Sb/As ratio indicated the presence of extreme sediment pollution for Zn, Cd, Pb, and Cr from anthropogenic sources. Research has shown that the easy-leached bottom sediment fraction contained in most cases more As(V) and Sb(V). But often Sb(V) concentration was equal as Sb(III), which can be released into the pelagic zone under favorable conditions. Even though As(V) and Sb(V) prevail in the reservoir bottom sediments, they can be transformed into As(III) and Sb(III) as a result of drastic changes in pH or redox potential. The Kozłowa Góra sediments are heavily polluted with Pb, Zn, Cd, and As, Cu, and Ni. The highest concentrations of the heavy metals were recorded in the middle of the tank and there was a small spatial variability. The migration of metals along the reservoir transect was closely related to its morphometry.

Metal(loid) speciation in a river subjected to industrial anthropopressure: chemometric and environmental studies

High-performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was applied to the speciation of arsenic [As(III), As(V), and AsB (arsenobetaine)], MMA (monomethylarsonic acid), DMA (dimethylarsinic acid), antimony [Sb(III) and Sb(V)], and chromium [Cr(III) and Cr(VI)] in water and bottom sediment samples collected from the urban Bytomka River (Poland). The main objective of the study was the research of As, Cr and Sb species in the Bytomka River, as well as the simplified three-stage sequential chemical extraction of bottom sediments according to the Institute for Reference Materials and Measurements (BCR). The contents of V, Mn, Co, Ni, Cu, Zn, Rb, Sr, Ag, Cd, Te, Ba, Tl, Pb, Fe, Ga, and U in the water and bottom sediments were tested using the ICP-MS technique. The risk assessment code (RAC) indicated a medium risk for As and a high risk for Sb to the environment. Sequential chemical extraction of bottom sediments showed that As and Cr were strongly demobilized. Sb was mainly bound with the ion-exchange fraction and posed a serious threat to the environment. Chemometric analysis with the (dis)similarity analysis and principal component analysis (PCA) allowed for visualization of the variability and correlations of the analyzed elements.

Health risks associated with the exposure to uranium and heavy metals through potable groundwater in Uttarakhand state of India

The present work aims to assess health risks associated with the exposure to uranium and heavy metals via potable groundwater in Uttarakhand state of India. For this purpose, potable groundwater samples were collected from the area and analyzed using LED fluorimetry and inductively coupled plasma mass spectrometry (ICPMS). The radiological (carcinogenic) and chemical (non-carcinogenic) risks associated with the exposure to uranium in majority of locations were observed below the safe limits suggested by WHO and USEPA. The levels of heavy metals present in potable groundwater were found well below the permissible limits recommended by WHO. An inter-comparison exercise between the results obtained with LED fluorimetry and ICPMS techniques was performed for the assurance of reliability and accuracy of results. The results were found in good agreement with each other.

Trace elemental profile investigation of illicit heroin for forensic intelligence

Abuse of illicit heroin is an endless threat to society and law enforcement. Beyond the routine procedure of detecting heroin in forensic laboratories, analytical information on the trace elemental profile of seized samples could aid investigations into establishing sample-to-sample linkages for forensic intelligence. This study is aimed at highlighting the grouping of seized illicit heroin samples based on their elemental profiles. A total of 155 seized heroin samples were analysed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and subsequently subjected to Principal Component Analysis (PCA). Among the 24 target elements measured, Ca, Na, Se, Zn, Al, Mn, Cd and Ba were the major impurities identified, while the remaining elements were present at trace levels. Decomposition of the elemental data by PCA generated two major clusters in a score plot, suggesting the possibility of clustering the various samples into two distinct groups. The ICP-MS technique was found to be sufficiently adequate to detect and quantify the 24 selected elements contained in illicit heroin samples. The histories of two distinct groups of elemental contamination may enable the establishment of a linkage among seized illicit heroin samples.

Boron Content of Some Foods Consumed in Istanbul, Turkey.

The boron content was determined in 42 different foods consumed in Istanbul, Turkey. Eleven species of fruit, ten species of vegetable, eight species of food of animal origin, four species of grain, two species of nuts, two species of legume, and five other kinds of foods were included to this study. They were analyzed by two methods: Inductively coupled plasma mass spectrometry (ICP-MS) technique and carminic acid assay, and the results of two methods were also compared. Boron concentration in foods ranged between 0.06-37.2mg/kg. Nuts had the highest boron content while foods of animal origin had the lowest. A strong correlation was found between the results of the carminic acid assay and the ICP-MS technique (p = 0.0001, Pearson correlation coefficient: r = 0.956). Bland Altman analysis also supported this correlation. ICP-MS is one of the most common, reliable, and powerful method for boron determination. The results of our study show that spectrophotometric carminic acid assay can provide similar results to ICP-MS, and the boron content in food materials can be also determined by spectrophotometric method.

Assessment of toxic elements in sediments of Linggi River using NAA and ICP-MS techniques

Fourteen sediment samples were collected along Linggi River, Malaysia. Neutron activation analysis (NAA) and inductively coupled plasma-mass spectrometry (ICP-MS) techniques were used in the determination of toxic element contents. The results showed that As, Cd and Sb concentrations were higher at all sampling stations, with enrichment factor values ranging from 17.7 to 75.0, 2.1 to 19.5 and 6.6 to 28.4, respectively. Elements of Pb and Zn) were also enriched at most of the sampling stations whilst Cu, Cr and Ni were shown as background levels. The sediment of Linggi River can be categorised as low (<8.0) to very high degree of contamination (>32.0). The mean concentrations of elements viz. Cd, Cr, Ni, Pb, Sb and Zn were lower than the threshold effect level (TEL) of FSQGs values except for As. The concentration of As (arsenic) was higher than PEL and PEC of FSQGs values.

Assessment of 1H NMR-based metabolomics analysis for normalization of urinary metals against creatinine

BackgroundProton nuclear magnetic resonance (1H NMR, or NMR) spectroscopy and inductively coupled plasma-mass spectrometry (ICP-MS) are commonly used for metabolomics and metal analysis in urine samples. However, creatinine quantification by NMR for the purpose of normalization of urinary metals has not been validated. We assessed the validity of using NMR analysis for creatinine quantification in human urine samples in order to allow normalization of urinary metal concentrations. MethodsNMR and ICP-MS techniques were used to measure metabolite and metal concentrations in urine samples from 10 healthy subjects. For metabolite analysis, two magnetic field strengths (600 and 700MHz) were utilized. In addition, creatinine concentrations were determined by using the Jaffe method. ResultsCreatinine levels were strongly correlated (R2=0.99) between NMR and Jaffe methods. The NMR spectra were deconvoluted with a target database containing 151 metabolites that are present in urine. A total of 50 metabolites showed good correlation (R2=0.7–1.0) at 600 and 700MHz. Metal concentrations determined after NMR-measured creatinine normalization were comparable to previous reports. ConclusionsNMR analysis provided robust urinary creatinine quantification, and was sufficient for normalization of urinary metal concentrations. We found that NMR-measured creatinine-normalized urinary metal concentrations in our control subjects were similar to general population levels in Canada and the United Kingdom.

Progress in Analysis of Neptunium in Environmental Samples by Inductively Coupled Plasma-Mass Spectrometry

In recent years, radionuclide monitoring and contamination control have been attached great importance. Wide attention has been paid to the measurement and analysis of Neptunium (237Np) as one of the radio-nuclides. With the development of mass-spectrometry technique, the inductively coupled plasma-mass spectrometry (ICP-MS) technique, with its outstanding advantage, has been widely applied to the measurement of237Np in environmental and biological samples. In this paper, the progress in analysis of237Np in environmental samples with ICP-MS technique is overviewed.

Geochemistry of Kolmani-1 Well Sediments from the Upper Benue Trough, Gongola Basin, Northeastern Nigeria

Aims: To assess the source rock characteristics and the depositional environment through Geochemical studies of sediment samples from the Upper Benue Trough. Place and Duration of Study: Department of Geology, Obafemi Awolowo University, Nigeria and The Activation Laboratory Ltd, Ontario, Canada between February 2011 and March 2012. Methodology: Eighteen samples made up of sand, shale, coaly shale, shaly sand and sandy shale, occurring between the depths of 18.3 m and 2725 m were analysed for thirty-four elements, comprising eight major, twelve trace, and fourteen rare earth elements (REE) using the Inductively Coupled PlasmaMass Spectrometry technique. Results: The results show that the sediments are compositionally rich in Al2O3 and Fe2O3. The low TiO2 values of compared to those of Post-Archean Australian average shale (PAAS) suggest that they were derived from more evolved felsic source rock. The relatively low average Rb/Sr and high Th/U ratios indicate that moderate to more intense weathering occurred in the source rock area. The absolute rare earth elements (REE) concentrations were in the order of coaly shale > shale > sandy shale > shaly sand > sand. Original Research Article British Journal of Applied Science & Technology, 4(20): 2931-2945, 2014 2932 Conclusion: The Al2O3/TiO2, Eu/Eu*, Th/Sc, La/Sc, Th/Co, La/Co, and Th/Cr ratios indicate that the sediments were probably derived from felsic source rocks. In addition, the high LREE/HREE ratios and the negative Eu anomaly also support felsic source rocks for the sediments whilst the very low V/Cr ratios indicate that these sediments were deposited under anoxic environment, consistent with the series of horst and graben structural framework model of the Benue Trough.

Etching of III-V Materials Determined by ICP-MS with Sub-Nanometer Precision

The use of inductively coupled plasma mass spectrometry (ICP-MS) is proposed in order to study the etching of III-V substrates at the sub nanometer level in diluted chemistries containing hydrochloric (HCl) or sulfuric acid (H2SO4). Based on the stability and the matrix effects of the sample, an optimal concentration of 100 mM HCl or H2SO4 was suggested for the insertion into the ICP-MS. The interferences originating from the acid matrices were effectively attenuated by the octopole reaction system (ORS) when operated in He mode, allowing for the In, Ga and As analytes to be quantified at a single ppb level with an accuracy of ±5% and a precision better than 5%. The presented detection limit, background equivalent concentration (BEC), spike recovery and stability data demonstrated that the ICP-MS technique could be used for determining the dissolved In, Ga and As analytes in a concentration range corresponding to the amount present in a sub nanometer layer.

Pharmacokinetics of cisplatin during hyperthermic intraperitoneal treatment of peritoneal carcinomatosis

Cisplatin during hyperthermic intraperitoneal chemotherapy (HIPEC) has not previously been measured with a selective technique. The primary aims were to examine the pharmacokinetics of active cisplatin and its monohydrated complex (MHC) during HIPEC using a specific measuring technique, to compare cisplatin's systemic absorption with oxaliplatin, and to compare active cisplatin levels to that of total platinum. Ten patients treated with cytoreductive surgery and HIPEC (cisplatin 50 mg/m(2),doxorubicin 15 mg/m(2)) were recruited. Blood and perfusate samples were drawn during and after HIPEC. Cisplatin analysis was conducted using liquid chromatography (LC) with post-column derivatization with diethyldithiocarbamate and compared with inductively coupled plasma-mass spectrometry (ICP-MS). The mean half-life (t1/2) of perfusate cisplatin was 18.4 min, with area under the time-concentration curve (AUC) 0-90 min of 2.87 mM·min and estimated 0-60 min of 2.45 mM·min. The absorption t1/2 was 9.0 min for cisplatin and 18.2 min for oxaliplatin. The ratio of total platinum to active cisplatin increased in a linear manner by time of perfusion. Cisplatin is absorbed quicker than oxaliplatin. Lowering the perfusion time to 60 min does not significantly change the pharmacokinetics of cisplatin, and is therefore to be considered. As the HIPEC perfusion progresses, the ICP-MS technique does not adequately reflect active cisplatin levels in the perfusate.