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Background: Potassium isotopic analysis is increasingly performed in both geological and biological contexts as a result of the introduction of MC-ICP-MS instrumentation either equipped with a collision/reaction cell or having the capability of working at "extra-high" mass resolution in order to deal with spectral interference caused by argon hydride (ArH + ) ions. Potassium plays an important role in the central nervous system, and its isotopic analysis could provide an enhanced insight into the corresponding processes, but K isotopic analysis of cerebrospinal fluid is challenging due to the small volume, a few microliter only, typically available. This work aimed at developing a method for determining the K isotopic signature of serum and cerebrospinal fluid at a final K concentration of 25 ng mL -1 using Faraday cup amplifiers equipped with a 10 13  Ω resistor., Results: Potassium isotope ratios obtained for reference materials measured at a final K concentration of 25 ng mL -1 were in excellent agreement with the corresponding reference values and the internal and external precision for the δ 41 K value was 0.11 ‰ (2SE, N = 50) and 0.10 ‰ (2SD, N = 6), respectively. The robustness against the presence of matrix elements and the concentration mismatch between sample and standard observed at higher K concentrations is preserved at low K concentration. Finally, K isotopic analysis of serum and cerebrospinal fluid (3-12 μL of sample) of healthy mice of both sexes was performed, revealing a trend towards an isotopically lighter signature for serum and cerebrospinal fluid from female individuals, however being significant for serum only., Significance: This work provides a robust method for high-precision K isotopic analysis at a concentration of 25 ng mL -1 . By monitoring both K isotopes, 39 K and 41 K, with Faraday cups connected to amplifiers with 10 13  Ω resistors, accurate K isotope ratio results are obtained with a two-fold improvement in internal and external precision compared to those obtained with the set-up with traditional 10 11  Ω resistors. The difference in the K isotope ratio in CSF and serum between the sexes, is possibly indicating an influence of the sex or hormones on the fractionation effects accompanying cellular uptake/release., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Recent papers on LA-ICP-MS have reported that certain elements are transported in particulate form, others in gaseous form and still others in a combination of both upon ablation of C-based materials. These two phases display different transport behaviour characteristics, potentially causing smearing in elemental maps, and could be processed differently in the ICP which raises concerns as to accuracy of quantification and emphasizes the need for matrix-matching of external standards. This work aims at a better understanding of two-phase sample transport by evaluating the peak profile changes observed upon varying parameters such as laser energy density and wavelength., Results: It is demonstrated that upon ablation of gelatin, elements are transported predominantly in particulate phase, but already at low laser energy density, a significant fraction of some elements is transported in the gaseous phase, which is even more expressed at higher energy density. This behaviour is element-specific since the ratio of the signal intensity for the analyte element transported in gas phase to the total signal intensity was 0 % for 23 Na, 43 % for 66 Zn and as high as 95 % for 13 C using a 193 nm laser. The results also suggest an effect of the laser wavelength, as all elements show either the same or higher amount of gas phase formation upon ablating with 213 nm versus 193 nm. It was even established that elements that fully occur in particulate form upon ablation using 193 nm laser radiation are partly converted into gaseous phase when using 213 nm., Significance: This work provides a thorough investigation of the underexposed phenomenon of two-phase sample transport upon ablation of biological samples upon via LA-ICP-MS. It is shown that for some elements a fraction of the ablated material is converted and transported in the gas phase, which can lead to significant smearing effects. As such, it is important to evaluate element-specific peak profiles on beforehand and, if necessary, adapt instrument settings and slow down data acquisition., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Frank Vanhaecke has patent #EP3195346B1 licensed to Teledyne Photon Machines., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Sulfur isotope ratios are often used as biogeochemical tracers to gain understanding of abiotic and biological processes involved in the sulfur cycle in both modern and ancient environments. There is however a lack of matrix-matched well-characterized isotopic reference materials that are essential for controlling the accuracy and precision. This study therefore focused on expanding and complementing the currently available sulfur isotope ratio data by providing the bulk sulfur isotopic composition, as determined using multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS), for a comprehensive set of commercially and/or readily available biological and geological reference materials. A total 7 isotopic reference materials and 41 elemental reference materials were studied. These reference materials include standards of terrestrial and marine animal origin, terrestrial plant origin, human origin, and geological origin. Different sample preparation protocols, including digestion and subsequent chromatographic isolation of S, were evaluated and the optimum approach selected for each matrix type. For achieving enhanced robustness, the sample preparation and sulfur isotope ratio measurements were done at two different laboratories for selected reference materials, while at one of the laboratories the measurements were additionally performed using two different MC-ICP-MS instruments. Determined δ 34 S VCDT and δ 33 S VCDT values compared well between the different laboratories, as well as between the different generation MC-ICP-MS instruments, and for standards that were previously characterized, our data are similar to literature values. The δ 34 S VCDT ranges determined for the different categories of the reference materials - terrestrial animal origin: +2 to +9‰, marine animal origin: +15 to +20‰, human origin: +6 to +10‰, terrestrial plant origin: -20 to +7‰, and geological origin: -12 to +21‰ - fit the expected values based on previous studies of similar types of matrices well. No significant mass-independent fractionation is observed when considering the expanded uncertainties for Δ 33 S V-CDT ., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2022 Elsevier B.V. All rights reserved.)

Single cell - tandem ICP-mass spectrometry (SC-ICP-MS/MS) was used for the determination of the absolute amount of Pt (coming from exposure to various concentration levels of cisplatin as a chemotherapeutic drug) and five endogenous elements (P, S, Fe, Cu and Zn) in individual human cells of three different types - Raji, Jurkat and Y79. Optimum conditions were obtained by using a sample introduction unit transporting cell suspension containing approx. 5 × 10 4  cells per mL at a flow rate of 10 μL min -1 to a nebulizer with narrow internal diameter (250 μm i.d.), mounted onto a total consumption spray chamber. Interference-free conditions were obtained in tandem MS mode (i) for P and S by pressurizing the collision/reaction cell (CRC) with O 2 and monitoring the PO + and SO  +  reaction product ions and (ii) for Fe by pressurizing the CRC with NH 3 and monitoring the Fe(NH 3 ) 2 + reaction product ion. The quantification approach was validated by comparison of the absolute amounts of the target elements (in fg per cell) as obtained using SC-ICP-MS/MS with those obtained after acid digestion of approx. 2 × 10 6  cells and subsequent solution ICP-MS/MS analysis ("bulk" analysis). A higher Pt cell content was observed upon increasing the concentration of the cisplatin solution the cells were exposed to during 24 h. The Pt mass per cell (fg) increased linearly as a function of the cisplatin concentration, but a higher Pt uptake was found in the case of Jurkat cells compared to the other cell types. A cell viability assay showed a lack of chemosensitivity to cisplatin below 200 μM for the Raji and Y79 cell line, but an IC 50 value of 11.1 ± 1.3 μM for Jurkat cells. This difference in chemo-responsiveness between the different cell types supported the difference in Pt uptake as indicated via SC-ICP-MS analysis. The increasing level of Pt did not have a marked effect on the contents of the endogenous elements monitored in Raji and Y79 cells, but a decrease in the P and S cell content upon increasing cisplatin treatment was observed for Jurkat cells. This can most likely be attributed to stress induced by the chemotherapeutic treatment in cells showing chemosensitivity towards cisplatin. The results also indicate differences in the absolute amount of endogenous element per cell between different cell types, suggesting the potential of SC-ICP-MS as a "metallo-fingerprinting" tool., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The devices used – the MVX-7100 μL sample introduction unit, the single-cell glassware and the AT8900 ICP-MS/MS instrument – were made available by Teledyne Cetac Technologies, Glass Expansion and Agilent Technologies, respectively., (Copyright © 2021 Elsevier B.V. All rights reserved.)

A sequential chromatographic separation procedure for subsequent high-precision isotopic analysis of Mg and Ca via multi-collector ICP-mass spectrometry (MC-ICP-MS) from a single aliquot of sample was developed and used for a variety of animal/human biofluids and tissues. The procedure consists of a one-stage Mg isolation protocol (for most of the sample types) and a three-stage isolation protocol for Ca. AG50W-X8 strong cation exchange resin was used for the isolation of Mg and Ca, while Sr-resin was used to additionally purify the Ca fraction from Sr. Potential effects on the Mg isotope ratio measurement results caused by the possible presence of concomitant matrix elements (Cu, Fe, Zn, Ca) were systematically evaluated. δ 26 Mg values were biased for a Fe/Mg ratio > 0.13 and a Ca/Mg ratio > 1.5, resulting in a shift towards a lighter Mg isotopic composition. It was shown that the Mg isotope ratio data for Mg standards, the isotopic reference materials ERM-AE143 and IRMM 009 and the biological samples investigated are located on a mass-dependent fractionation line. Biological reference materials and commercially available serum samples were analyzed for both their Mg and Ca isotope ratios. For some of the biomaterials analyzed, the Ca isotope ratio data as obtained using MC-ICP-MS were further validated via their determination using double-spike thermal ionization mass spectrometry (DS-TIMS). The expanded uncertainty for δ 26 Mg was ≤ 0.12‰ and for δ 44 /42 Ca ≤ 0.29‰. Biological fluids and tissues of mice were analyzed to characterize the body distribution of the stable isotopes of Mg and Ca. The isotopic variability among the body compartments was about 1.5‰ for Mg and 1.0‰ for Ca. Among the tissues explored, muscle tissue shows the lightest Mg and Ca isotopic compositions and liver the heaviest Mg and Ca isotopic compositions, respectively., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this work, the effects of using collision/reaction cell (CRC) technology in quadrupole-based ICP-MS (ICP-QMS) instrumentation operated in single-particle (SP) mode have been assessed. The influence of (i) various CRC gases, (ii) gas flow rates, (iii) nanoparticle (NP) sizes and (iv) NP types was evaluated using Ag, Au and Pt NPs with both a traditional ICP-QMS instrument and a tandem ICP-mass spectrometer. It has been shown that using CRC technology brings about a significant increase in the NP signal peak width (from 0.5 up to 6 ms). This effect is more prominent for a heavier gas (e.g., NH 3 ) than for a lighter one (e.g., H 2 or He). At a higher gas flow rate and/or for larger particle sizes >100 nm), the NP signal duration was prolonged to a larger extent. This effect of using CRC technology has been further demonstrated by characterizing custom-made 50 and 200 nm Fe 3 O 4 NPs (originally strongly affected by the occurrence of spectral overlap) using different CRC approaches (H 2 on-mass and NH 3 mass-shift). The use of NH 3 (monitoring of Fe as the Fe(NH 3 ) 2 + reaction product ion at m/z = 90 amu) induces a significant peak broadening compared to that observed when using H 2 (6.10 ± 1.60 vs. 0.94 ± 0.49 ms). This extension of transit time can most likely be attributed to the collisions/interactions of the ion cloud generated by a single NP event with the CRC gas and it even precludes 50 nm Fe 3 O 4 NPs to be detected when using the NH 3 mass-shift approach. Based on these results, the influence of a longer peak width on the accuracy of SP-ICP-MS measurement data (NP size, particle number density and mass concentration) must be taken into account when using CRC technology as a means to overcome spectral overlap. To mitigate the potential detrimental effect of using CRC technology in the characterization of NPs via SP-ICP-MS(/MS), the use of light gases and low gas flow rates is recommended., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This work evaluates the possibility of placement of high-resolution imaging and single-cell analysis via laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) within precision medicine by assessing the suitability of LA-ICP-MS as a micro-analytical technique for the localization and quantification of membranous receptors in heterogeneous cell samples that express both the membrane-bound receptors C-X-C chemokine receptor type 4 (CXCR4) and epidermal growth factor receptor (EGFR). Staining of the breast cancer cell lines MDA-MB-231 X4 and MDA-MB-468 was achieved using receptor-specific hybrid tracers, containing both a fluorophore and a DTPA single-lanthanide chelate. Prior to LA-ICP-MS imaging, fluorescence confocal microscopy (FCM) imaging was performed to localize the receptors, hereby enabling direct comparison. Based on the different expression levels of CXCR4 and EGFR, a distinction could be made between the cell lines using both imaging modalities. Furthermore, FCM and LA-ICP-MS demonstrated complementary characteristics, as a more distinct discrimination could be made between both cell lines based on the EGFR-targeting hybrid tracer via LA-ICP-MS, due to the intrinsic CXCR4-related green fluorescent protein (GFP) signal present in the MDA-MB-231 X4 cells. Employing state-of-the-art LA-ICP-MS instrumentation in bidirectional area scanning mode for sub-cellular imaging of MDA-MB-231 X4 cells enabled the specific binding of the CXCR4-targeting hybrid tracer to the cell membrane to be clearly demonstrated. The stretching of cells over the glass substrate led to a considerably higher signal response for pixels at the cell edges, relative to the more central pixels. The determination of the expression levels of CXCR4 and EGFR for the MDA-MB-468 cell line was performed using LA-ICP-MS single-cell analysis (sc-LA-ICP-MS) and external calibration, based on the quantitative ablation of Ho-spiked dried gelatin droplet standards. Additionally, a second calibration approach was applied based on spot ablation of highly homogeneous dried gelatin gels in combination with the determination of the ablated volume using atomic force microscopy (AFM) and yielded results which were in good agreement with the expression levels determined via flow cytometry (FC) and mass cytometry (MC). Hybrid tracers enable a direct comparison between (i) FCM and LA-ICP-MS imaging for the evaluation of the microscopic binding pattern and between (ii) FC, MC and sc-LA-ICP-MS for the quantification of receptor expression levels in single cells., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The capabilities of Cu isotope ratio measurements are often restricted by the small volumes of sample available and/or their low Cu concentration. In this work, an analytical approach was developed for performing Cu isotopic analysis via multi-collector ICP-mass spectrometry (MC-ICP-MS) at ultra-trace level using Ga as an internal standard for mass bias correction. The minimum concentration of Cu required for accurate and precise isotope ratio measurements was established to be 20 μg L -1 with wet plasma conditions and 5 μg L -1 with dry plasma conditions. The use of Ga as an internal standard for mass bias correction provided several advantages compared to Ni, i.e. improved internal precision on δ 65 Cu values and lower blank levels. Ga can also be used at a 4-fold lower concentration level than Ni. However, in wet plasma conditions, the signals of 36 Ar 16 O 2 1 H + and 40 Ar 15 N 16 O + interfered with the signals of 69 Ga + and 71 Ga + , respectively, while in dry plasma conditions, realized by the use of a desolvation unit, 69 Ga + suffered from spectral interference from 40 Ar 14 N 2 1 H + . These interferences were resolved by using medium mass resolution. For validation purposes, the approach was applied to commercially available blood and serum samples. The δ 65 Cu values for the samples measured at a concentration level of 5 μg L -1 Cu and 5 μg L -1 Ga using dry plasma conditions were in good agreement with those obtained for isotope ratio measurements at the "standard" concentration level of 200 μg L -1 Cu and 200 μg L -1 Ni using wet plasma conditions. In addition, the δ 65 Cu values obtained for micro-samples of serum/blood (volume of 100 µL) were in good agreement with the corresponding ones obtained using the "standard" volume for isotopic analysis (500 μL)., (Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.)

A novel quantification approach, compensating for the effect of gradient elution on the instrumental response during reversed phase high-performance liquid chromatography - inductively coupled plasma - tandem mass spectrometry analysis, has been developed and validated. As a proof of concept, diclofenac and its related compounds, including its major metabolite i.e. 4'-hydroxy-diclofenac, have been quantitatively determined in human plasma matrix. An inductively coupled plasma - tandem mass spectrometer has been applied for the interference-free determination of Cl as 35 ClH 2 + using H 2 as a reaction gas in the collision/reaction cell. The effect of the eluent composition on the instrumental response for Cl has been thoroughly investigated for the most common organic solvents in reversed phase high-performance liquid chromatography, i.e. methanol and acetonitrile. A proper mathematical function describing the effect of the eluent composition on the sensitivity for Cl, monitored as 35 ClH 2 + , permitted adequate correction for the otherwise detrimental effect of gradient elution for both solvents. Validation using synthetically degraded diclofenac samples spiked with its major metabolite, 4'-hydroxy-diclofenac, demonstrated appropriate accuracy (recovery for 4'-hydroxy-diclofenac between 95 and 105%) and >90% and >80% recovery for Cl using acetonitrile and methanol, respectively. When applied to spiked human plasma samples (the most important matrix in drug metabolism studies), a satisfactory accuracy (recovery of 92-98%) and precision (<4% RSD) were established for both 4'-hydroxy-diclofenac and diclofenac. The limit of quantification for Cl (as diclofenac) using the novel method was 0.05 mg L -1 . This value can be significantly improved (to 0.002 mg L -1 ) via on-line sample pre-concentration using a trapping chromatographic column and a time-programmable 10 ports/2 positions micro valve., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Two-dimensional elemental mapping (bioimaging) via laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was performed on 5 μm thick formalin-fixed, paraffin-embedded kidney tissue sections from Cynomolgus monkeys administered with increasing pharmacological doses of cisplatin. Laterally resolved pixels of 1 μm were achieved, enabling elemental analysis on a (sub-)cellular level. Zones of high Pt response were observed in the renal cortex, where proximal tubules are present, the epithelium of which is responsible for partial reabsorption of cisplatin. Histopathological evaluation, of hematoxylin and eosin-stained serial sections, adjacent to the sections probed via LA-ICP-MS, revealed minimal to mild cisplatin-related lesions (<100 μm) in the renal cortex. Necrotic proximal tubules with sloughed epithelial cells in their lumen could be linked directly to the areas with the highest accumulation of cisplatin, indicating a direct link between cellular concentration and toxicity, thereby providing more insight into the mechanisms through which renal damage occurs., (Copyright © 2016 Elsevier B.V. All rights reserved.)

This paper reports on an evaluation of the suitability of a novel sample collection approach, volumetric absorptive micro-sampling (VAMS), in the context of the determination of ultra-trace concentrations of prosthesis-related metals (Al, Ti, V, Co, Cr, Ni, Sr and Zr) in whole blood. In a first phase, a simple dilute-and-shoot approach (100-fold dilution) followed by tandem ICP - mass spectrometry (ICP-MS/MS) analysis was developed for the accurate and sensitive determination of the target elements. The ICP-MS/MS method relies on the use of mass shift reactions proceeding when pressurizing the collision/reaction cell (CRC) with CH 3 F/He for dealing with spectral overlap. Limits of detection (LoDs) between 0.3 and 30 ng L -1 were attained in a multi-element approach. The accuracy of the method was demonstrated via successful analysis of the reference materials Seronorm Whole Blood Levels 1 and 3, and real venous blood samples, spiked with the target elements at different concentration levels (5-50 μg L -1 ). Although the implementation of VAMS devices introduced contamination problems for Al, Cr and Ni, VAMS followed by ICP-MS/MS analysis shows potential for future real-life routine applications when assessing levels of Ti, V, Co, Sr and/or Zr., (Copyright © 2016 Elsevier B.V. All rights reserved.)

This paper is intended as a tutorial review on the use of inductively coupled plasma - tandem mass spectrometry (ICP-MS/MS) for the interference-free quantitative determination and isotope ratio analysis of metals and metalloids in different sample types. Attention is devoted both to the instrumentation and to some specific tools and procedures available for advanced method development. Next to the more typical reaction gases, e.g., H2, O2 and NH3, also the use of promising alternative gases, such as CH3F, is covered, and the possible reaction pathways with those reactive gases are discussed. A variety of published applications relying on the use of ICP-MS/MS are described, to illustrate the added value of tandem mass spectrometry in (ultra)trace analysis., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Ti is frequently used in implants and prostheses and it has been shown before that the presence of these in the human body can lead to elevated Ti concentrations in body fluids such as serum and urine. As identification of the exact mechanisms responsible for this increase in Ti concentrations, and the risks associated with it, are not fully understood, it is important to have sound analytical methods that enable straightforward quantification of Ti levels in body fluids (for both implanted and non-implanted individuals). Until now, only double-focusing sector field ICP-mass spectrometry (SF-ICP-MS) offered limits of detection that are good enough to deal with the very low basal levels of Ti in human serum. This work reports on the development of a novel method for the accurate and precise determination of trace levels of Ti in human serum samples, based on the use of ICP-MS/MS. O2 and NH3/He have been compared as reaction gases. While the use of O2 did not enable to overcome all spectral interferences, it has been shown that conversion of Ti(+) ions into Ti(NH3)6(+) cluster ions by using NH3/He as a reaction gas in an ICP-QQQ-MS system, operated in MS/MS mode, provided interference-free conditions and sufficiently low limits of detection, down to 3 ng L(-1) (instrumental detection limit obtained for the most abundant Ti isotope). The accuracy of the method proposed was evaluated by analysis of a Seronorm Trace Elements Serum L-1 reference material and by comparing the results obtained with those achieved by means of SF-ICP-MS. As a proof-of-concept, the newly developed method was successfully applied to the determination of Ti in serum samples obtained from individuals with and without Ti-based implants. All results were found to be in good agreement with those obtained by means of SF-ICP-MS. The typical basal Ti level in human serum was found to be <1 μg L(-1), while values in the range of 2-6 μg L(-1) were observed for implanted patients., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this paper, an exploration of the capabilities and limitations of pulsed radiofrequency glow discharge time-of-flight mass spectrometry (GD-TOFMS) for the determination of the precious metals Ag, Au, Pd, Pt and Rh in lead buttons obtained by Pb fire assay is reported on. Since the matrix consists almost entirely of lead (>99%), the occurrence of doubly charged Pb (Pb(2+)) ions can hinder accurate determination of Rh. This problem was counteracted by relying on the time-resolved formation of different ion types over the pulse period of the glow discharge, which allows discrimination against the Pb(2+) ions. The formation of ArCu(+) ions as a result of the use of a copper anode was assessed to pose no threat to the accuracy of the results obtained for the set of samples analyzed as its contribution to the total signal at m/z=103 could be adequately corrected for. The method developed was evaluated in terms of accuracy and precision using a set of Pb button standards with analyte concentrations between 5 and 100 μg g(-1). For the purpose of validation, a 10 μg g(-1) standard was considered as a sample. Overall, an acceptable accuracy was obtained with a bias of <5% between the experimental results and the corresponding reference values, except for Au, for which a larger deviation occurred. Precision values (repeatability) of typically <5% relative standard deviation (RSD) (for N=3) were obtained and the limits of detection (LODs) vary from ~0.020 μg g(-1) for Ag to ~0.080 μg g(-1) for Pt., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Visualization of elemental distributions in thin sections of biological tissue is gaining importance in many disciplines of biological and medical research. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and scanning micro-X-ray fluorescence spectrometry (micro-XRF) are two widely used microanalytical techniques for elemental mapping. This article compares the capabilities of the two techniques for imaging the distribution of selected elements in the model organism Daphnia magna in terms of detection power and spatial resolution. Sections with a thickness of 10 and 20 microm of the fresh water crustacean Daphnia magna were subjected to LA-ICP-MS and micro-XRF analysis. The elemental distributions obtained for Ca, P, S and Zn allow element-to-tissue correlation. LA-ICP-MS and micro-XRF offer similar limits of detection for the elements Ca and P and thus, allow a cross-validation of the imaging results. LA-ICP-MS was particularly sensitive for determining Zn (LOD 20 microg g(-1), 15 microm spot size) in Daphnia magna, while the detection power of micro-XRF was insufficient in this context. However, LA-ICP-MS was inadequate for the measurement of the S distributions, which could be better visualized with micro-XRF (LOD 160 microg g(-1), 5 s live time). Both techniques are thus complementary in providing an exhaustive chemical profiling of tissue samples., (2010 Elsevier B.V. All rights reserved.)

In this review, the literature on the subject of electrothermal vaporization-inductively coupled plasma-mass spectrometry (ETV-ICP-MS) published during the last decade is reviewed with a double purpose: an evaluation of the possibilities of this technique for dealing with very challenging analytical applications on the one hand, and the establishment of a reference guide for method development in ETV-ICP-MS on the other. First, a brief introduction, pointing out the milestones in the development of the technique will provide the reader with a better understanding of the present situation of ETV-ICP-MS and its future perspective. After a section on the basic processes occurring in the furnace and during analyte transport, a guide for method development for challenging analytical applications is proposed, based on the existing literature. Next, the latest contributions in the main application areas of the field are reviewed, with special attention to the most challenging ones: i.e. speciation, "thermal" resolution, enabling complex matrixes to be analyzed and spectral overlap to be avoided, and the direct analysis of slurries and solid samples. Finally, the advantages obtained by coupling an ETV unit to newer types of ICP-MS instrumentation, equipped with collision/reaction cells, time-of-flight (TOF) or sector field (SF) spectrometers, are also discussed.