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A new low-cost device suitable for the recently presented sample introduction technique to inductively coupled plasma mass spectrometry (ICP MS), diode laser thermal vaporization (DLTV), is described. DLTV ICP MS is suitable for quantitative elemental analysis of low volume liquid samples and offers an alternative to commonly used liquid sample introduction into inductively coupled plasma. In contrast to the existing sample introduction systems based on laser ablation, the technique relies on low-cost components: a diode laser, a simple laboratory-built cell and a strip of filter paper. The aerosol generation by DLTV is carried out in a simple cell made up of a glass tube, a near infrared continuous- wave diode laser and a common syringe pump. The cell is characterized by minimal dead volume, which reduces turbulent flow and provides very fast wash-out. The paper substrate can hold up to 24 samples; an analysis time per sample of ~4.7 s has been achieved. The device performance was optimized, compared to a commercial ablation system and applied to the determination of lead and cadmium in whole human blood without any sample treatment. A prearranged calibration set was printed on the paper strip using a piezoelectric dispenser. [ABSTRACT FROM AUTHOR]

A silica sol–gel technique was applied to the preparation of pellets of agricultural soils for determination of trace elements by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). For the purpose of evaluation of feasibility of the LA-ICP-MS technique for quantitative determination, elemental contents in twenty two spiked archive agricultural soils and three CRMs (GBW07405, GBW07406, and GBW07407) were determined by independent analytical techniques, namely by inductively coupled plasma optical emission spectrometry with pneumatic nebulization (PN-ICP-OES) after total decomposition with a mixture of acids, and by energy dispersive X-ray fluorescence (ED-XRF) spectrometry analysis of pellets prepared with a wax binder. Ablation was carried out with a Nd:YAG laser at 213 nm. Possible matrix interferences associated with ablation of the multiphase soil material were anticipated and therefore, the sequential extraction procedure was employed for fractionation analysis to determine elemental concentrations, in particular soil constituents, for explaining potential deviations of LA-ICP-MS analyses. Methods were compared based on the determination of ordinarily monitored trace elements Cu, Cr, Ni, Pb and Zn in archive soils and certified reference materials. The PN-ICP-OES, ED-XRF and LA-ICP-MS methods were compared by means of linear regression analysis to search for a possible systematic proportional or constant error. Besides the ordinary least-squares linear regression method, also weighted least squares, orthogonal, Deming, maximum likelihood and Passing–Bablok regressions were employed. The Bland–Altman plot and score plot based on principal component analysis (PCA) were used for visual comparison. [ABSTRACT FROM AUTHOR]

The paper presents the results of aluminium determinations in ground water samples of the Miocene aquifer from the area of the city of Poznań (Poland). The determined aluminium content amounted from <0.0001 to 752.7 $\upmu $g L. The aluminium determinations were performed using three analytical techniques: graphite furnace atomic absorption spectrometry (GF-AAS), inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). The results of aluminium determinations in groundwater samples for particular analytical techniques were compared. The results were used to identify the ascent of ground water from the Mesozoic aquifer to the Miocene aquifer in the area of the fault graben. Using the Mineql+ program, the modelling of the occurrence of aluminium and the following aluminium complexes: hydroxy, with fluorides and sulphates was performed. The paper presents the results of aluminium determinations in ground water using different analytical techniques as well as the chemical modelling in the Mineql+ program, which was performed for the first time and which enabled the identification of aluminium complexes in the investigated samples. The study confirms the occurrence of aluminium hydroxy complexes and aluminium fluoride complexes in the analysed groundwater samples. Despite the dominance of sulphates and organic matter in the sample, major participation of the complexes with these ligands was not stated based on the modelling. [ABSTRACT FROM AUTHOR]

Here we present a novel coupling of thin-layer chromatography (TLC) to diode laser thermal vaporization inductively coupled plasma mass spectrometry (DLTV ICP MS). DLTV is a new technique of aerosol generation which uses a diode laser to induce pyrolysis of a substrate. In this case the cellulose stationary phase on aluminum-backed TLC sheets overprinted with black ink to absorb laser light. The experimental arrangement relies on economic instrumentation: an 808-nm 1.2-W continuous-wave infrared diode laser attached to a syringe pump serving as the movable stage. Using a glass tubular cell, the entire length of a TLC separation channel is scanned. The 8-cm long lanes were scanned in ∼35 s. The TLC – DLTV ICP MS coupling is demonstrated on the separation of four cobalamins (hydroxo-; adenosyl-; cyano-; and methylcobalamin) with limits of detection ∼2 pg and repeatability ∼15 % for each individual species. [ABSTRACT FROM AUTHOR]

In this work, a novel approach based on off-line coupling of a single run of capillary electrophoresis (CE) separation to both matrix-assisted laser desorption/ionization (MALDI) and substrate-assisted laser desorption inductively coupled plasma (SALD ICP) mass spectrometry (MS) is presented. Using a liquid junction and subatmospheric deposition chamber, CE fractions were extracted from a separation capillary and collected as 20-nL droplets on a custom-built polyethylene terephthalate glycol (PETG) target plate coated with a 10-nm gold layer which guaranteed compatibility with both MALDI and SALD ICP techniques. The MALDI matrix solution was then added to the produced spots. After it was dried, the separation record was consecutively analyzed in MALDI MS and ICP MS instruments. Thus, both proteomic and metallomic information was obtained off-line from a single CE run. The concept was demonstrated by the analysis of a mixture of rabbit liver metallothionein isoforms. In an additional study, the droplets representing the archived separation record were alternately mixed with two different MALDI matrices to obtain complementary information on both the apoproteins and their complexes with metals from a single separation run. The presented technique is a viable alternative to online coupling of column separation to electrospray MS and nebulizer ICP MS. [ABSTRACT FROM AUTHOR]

The nickel and zinc contamination of algae on a cellulose filter was studied with double pulse 1064–1064 nm laser-induced breakdown spectroscopy (LIBS). Samples of the green alga Desmodesmus subspicatus were contaminated with zinc and nickel. The surface concentrations on the filter calculated from the reference Inductively Coupled Plasma Mass Spectrometry analysis were 25 and 64 ng cm−2 for nickel and zinc respectively. The algae are resting on the filter after drying and a double adhesive tape was used to fix the sample on the microscopic glass. During optimization method a compromise of 23–30 mJ pulse energies were set for maintaining a detectable or highest signal intensity of the analyte and not destroying the filter. Best conditions for maximum analyte signal and minimum deviation between the spectral behaviour of the analyte and the compared line of Na I, K I, Mg I, Mg II, Mn I, Mn II, Ca I, Ca II, and C I was 700 ns gate delay and 0 s interpulse delay. The deviation was rather more influenced with the signal-to-noise ratio of the analyte line than the closeness of the upper-level energies of the compared lines. The filter without algae showed systematically lower electron number density and total emissivity by units of percents than the filter with algae. [Display omitted] • plasma behaviour study on filter with contaminated algae. • optimization of the experimental parameters for LIBS on the filter. • comparison of spectral lines behaviour for possible matrix effects suppression. [ABSTRACT FROM AUTHOR]

Abstract The dynamics of aerosol particles formed during nanosecond laser ablation of glass and steel samples was studied in the Laser Ablation – Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) system. In order to follow the evolution of particle size distribution with high time resolution during the laser ablation process, two fast response aerosol spectrometers were used. Engine Exhaust Particle Sizer (EEPS) together with Optical Particle Sizer (OPS) provided Particle Size Distribution (PSD) in the range 5.6 nm – 10 μm with the integration time of 1 s. To obtain additional information about the PSD of larger particles (0.5–10 μm) in more detail, an Aerodynamic Particle Sizer (APS) recorded average PSD of each ablation (80 s). To investigate the effect of the sample matrix on aerosol dynamics and composition, glass NIST 610 and steel F4 samples were studied. Spot and line ablation mode was applied to compare the behavior of both ablation modes in time. The degree of thermal effect and fractionation was studied from the structure and size of ablation craters, the structure of particles and the LA-ICP-MS signal. The ablation process was influenced mostly by the material itself even if the ablation mode also plays an important role on the formation of aerosol. A significant correlation of ICP-MS signal with a concentration of particles >300 nm was observed. Graphical abstract Unlabelled Image Highlights • LA-ICP-MS analysis was complemented by aerosol spectrometers. • Highly time resolved particle size distribution was measured during LA. • Size distribution of particles <300 nm is mostly influenced by ablation mode. • Size distribution of particles >300 nm is mostly influenced by sample properties. • Correlation of ICP-MS signal and concentration of particles >300 nm was observed. [ABSTRACT FROM AUTHOR]

A LIBS equipment operating at 532 nm was optimized and used for sulfur determination in concrete samples. The influence of He atmosphere in a gas-tight chamber (1000–200 mbar) on S I 921.29 nm line sensitivity, signal-to-background and signal-to-noise ratio was studied at gate delays 100–2000 ns. Wide range of gate delays from 500 to about 1000 ns and pressures from several hundreds of mbar to the atmospheric pressure can be used for the desired detection of sulfur. The LIBS quantification was done using a simple calibration method. A synthetic limestone enriched by defined amounts of sodium sulfate was newly employed for direct quantification of S in concrete. This powder material was pressed into pellets and ablated with the LIBS system. The average content of sulfur as SO 3 in the samples was 0.41–0.70 wt% by LIBS and 0.43–0.61 wt% by a reference standard procedure employing gravimetry and Inductively Coupled Plasma Triple Quad Mass Spectrometry (ICP-QQQMS). The uncertainty of the yielded LIBS results covers also the dispersion of the points in the calibration line and ranges from 16 to 28% at the probability level of 95%. The uncertainty of the ICP-QQQMS results was almost 10%. No correction on different signal response on the limestone and on the concrete was necessary. [ABSTRACT FROM AUTHOR]

LA-ICP-MS method was utilized for the elemental mapping of H . diminuta tissue as possible bio-accumulating organism. Since no suitable commercial standards for analysis of H . diminuta sections are available, synthetic matrix similar standards containing 0, 5, 10, 20 and 30 mg kg − 1 of Fe and Pb as well as 0, 50, 100, 200, 300, 400 and 500 mg kg − 1 of Zn were prepared by spiking agarose gel with elements of interest. Two different laser ablation ICP-MS systems were used, namely 213 nm LA-ICP-(Q)MS and 193 nm LA-ICP-(SF)MS, and compared in terms of their detection limits and achievable goodness of fit of linear calibration dependencies. Carbon 12 C + was used as internal reference element to correct for the different tissue density and absorption rates. The prepared set of multi-elemental agarose gel standards was utilized for the quantitative elemental mapping of H . diminuta paraffin-embedded thin sections using the 213 nm solid state Nd:YAG coupled to ICP-(Q)MS. The content of Zn as biogenic element was found to be relatively homogeneously distributed within the cross section of proglottid, primarily in reproductive structures (uterus, fertilized eggs) while the Pb elemental distribution was found to be more concentrated in the tegument (surface). [ABSTRACT FROM AUTHOR]

A new multiple detection arrangement for liquid chromatography (LC) that supplements conventional electrospray ionization (ESI) mass spectrometry (MS) detection with two complementary detection techniques, matrix-assisted laser desorption/ionization (MALDI) MS and substrate-assisted laser desorption inductively coupled plasma (SALD ICP) MS has been developed. The combination of the molecular and elemental detectors in a single separation run is accomplished by utilizing a commercial MALDI target made of conductive plastic. The proposed platform provides a number of benefits in today's metalloproteomic applications, which are demonstrated by analysis of a metallothionein mixture. To maintain metallothionein complexes, separation is carried out at a neutral pH. The effluent is split; a major portion is directed to ESI MS while the remaining 1.8% fraction is deposited onto a plastic MALDI target. Dried droplets are overlaid with MALDI matrix and analysed consecutively by MALDI MS and SALD ICP MS. In the ESI MS spectra, the MT isoform complexes with metals and their stoichiometry are determined; the apoforms are revealed in the MALDI MS spectra. Quantitative determination of metallothionein isoforms is performed via determination of metals in the complexes of the individual protein isoforms using SALD ICP MS. [ABSTRACT FROM AUTHOR]

The particle size distribution of dry aerosol originating from laser ablation of glass material was monitored simultaneously with Laser Ablation – Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) analysis and two aerosol spectrometers – Fast Mobility Particle Sizer (FMPS) and Aerodynamic Particle Sizer (APS). The unique combination of LA-ICP-MS and FMPS offers the possibility of measuring the particle size distribution every 1 s of the ablation process in the size range of 5.6–560 nm. APS extends the information about particle concentration in the size range 0.54–17 μm. Online monitoring of the dry aerosol was performed for two ablation modes (spot and line with a duration of 80 s) with a 193 nm excimer laser system, using the glass reference material NIST 610 as a sample. Different sizes of laser spot for spot ablation and different scan speeds for line ablation were tested. It was found that the FMPS device is capable of detecting changes in particle size distribution at the first pulses of spot laser ablation and is suitable for laser ablation control simultaneously with LA-ICP-MS analysis. The studied parameters of laser ablation have an influence on the resulting particle size distribution. The line mode of laser ablation produces larger particles during the whole ablation process, while spot ablation produces larger particles only at the beginning, during the ablation of the intact layer of the ablated material. Moreover, spot ablation produces more primary nano-particles (in ultrafine mode size range < 100 nm) than line ablation. This effect is most probably caused by a reduced amount of large particles released from the spot ablation crater. The larger particles scavenge the ultrafine particles during the line ablation mode. [ABSTRACT FROM AUTHOR]

Single particle inductively coupled plasma mass spectrometry (SP-ICPMS) has been generally accepted as a powerful tool in the field of nanoanalysis. The method has usually been restricted to direct nanoparticle (NP) introduction using nebulization or microdroplet generation systems. In this work, AuNPs are introduced into ICPMS by substrate-assisted laser desorption (SALD) directly from a suitable absorbing plastic surface using a commercial ablation cell for the first time. In SALD, desorption of individual NPs is mediated using a frequency-quintupled Nd:YAG laser (213 nm) operated at a rather low laser fluence. Conditions including laser fluence, laser beam scan rate, and carrier gas flow rate were optimized in order to gain the highest AuNP transport efficiency and avoid AuNP disintegration within the laser irradiation. The method was demonstrated on a well-characterized reference material, 56 nm AuNPs with a transport efficiency of 61% and commercially available 86 nm AuNPs. Feasibility of our technique for NP detection and characterization is discussed here, and the results are compared with an established technique, nebulizer SP-ICPMS. [ABSTRACT FROM AUTHOR]

The chromium and copper contamination of algae on a filter was directly monitored with laser-induced breakdown spectroscopy (LIBS) as a demonstration of LIBS capabilities. Liquid samples of the green alga Desmodesmus subspicatus were intentionally contaminated with chromium, incubated, filtered, and the filters with the algae were analysed. Inductively coupled plasma mass spectrometry (ICP-MS) was used as a reference method. One half of the filter with the algae was dissolved and analysed as a solution with ICP-MS and the second half was subjected to the LIBS and laser ablation-ICP-MS analysis. Chromium and copper were attributable to the algae contamination and detectable with LIBS. The results from the LIBS provided almost equivalent information about the relative changes of the Cr and Cu concentration in the algae. The sensitivity of LIBS with a Czerny-Turner spectrometer was fully comparable with the ICP-MS procedure. The trends from LIBS were more similar to the LA-ICP-MS ones. It means that the algae growth inhibition in dependence on the chromium or copper content can be alternatively monitored with LIBS instead of the complicated decomposition procedure in ICP-MS analysis. [Display omitted] • first time direct analysis of algae cells contamination with LIBS • no further sample processing after the filtration of the algae cells • substantial facilitating by omitting the laborious decomposition for ICP-MS or preparation of pellets for LIBS [ABSTRACT FROM AUTHOR]

Abstract: LA-ICP-MS and solution based ICP-MS in combination with electron microprobe are presented as a method for the determination of the elemental spatial distribution in fish scales which represent an example of a heterogeneous layered bone structure. Two different LA-ICP-MS techniques were tested on recent common carp (Cyprinus carpio) scales: [(a)] A line scan through the whole fish scale perpendicular to the growth rings. The ablation crater of 55μm width and 50μm depth allowed analysis of the elemental distribution in the external layer. Suitable ablation conditions providing a deeper ablation crater gave average values from the external HAP layer and the collagen basal plate. [(b)] Depth profiling using spot analysis was tested in fish scales for the first time. Spot analysis allows information to be obtained about the depth profile of the elements at the selected position on the sample. The combination of all mentioned laser ablation techniques provides complete information about the elemental distribution in the fish scale samples. The results were compared with the solution based ICP-MS and EMP analyses. The fact that the results of depth profiling are in a good agreement both with EMP and PIXE results and, with the assumed ways of incorporation of the studied elements in the HAP structure, suggests a very good potential for this method. [Copyright &y& Elsevier]

A novel off-line coupling of capillary electrophoresis (CE) and inductively coupled plasma mass spectrometry (ICPMS) is reported here. The coupling interface is based on the connection of a separation capillary to a deposition capillary via a liquid junction maintaining high separation efficiency and sample utilization due to the self-focusing effect and lack of pressure-induced flow in comparison with nebulizer-like interfaces. The separation is recorded in the form of droplets of CE effluent on a suitable substrate--a poly(ethylene terephthalate) glycol (PETG) sample plate placed inside a partially evacuated chamber. Substrate-assisted laser desorption (SALD) is used to vaporize the sample fractions and to enable further transfer to the ICPMS. The mechanism of SALD is examined using model samples deposited on a variety of substrates. The highest response is obtained for a PETG substrate; sample desorption due to ablation of PETG is found to outweigh direct ablation of sample. Detection limits are given for several metal elements. Finally, a rapid (2.5-min), high-resolution separation of CrIII/CrVI species injected in subpicomolar quantity is shown. [ABSTRACT FROM AUTHOR]

Abstract: The feasibility of depth profiling of zinc-coated iron sheets by laser ablation (LA) was studied using an Nd:YAG laser (1064 nm) with inductively coupled plasma optical emission spectrometry (ICP-OES), and an excimer ArF* laser (193 nm) with a beam homogenizer. The latter was coupled to an ICP with mass spectrometry (ICP-MS). Fixed-spot ablation was applied. Both LA systems were capable of providing depth profiles that approach the profiles obtained by glow discharge optical emission spectroscopy (GD-OES) and electron probe X-ray microanalysis (EPXMA). For Nd:YAG laser an artefact consisting of zinc depth profile signal tailing appeared, enlarging thus erroneously diffusional coating–substrate interface profile. However, the ArF* system partially reduced but not suppressed that phenomenon. For both LA systems the Fe signal from the substrate increased with depth as expected and reached a plateau. The depth resolution (depth range corresponding to 84%–16% change in the full signal) achieved was several micrometers. Ablation rate was found to depend on ablation spot area at constant irradiance. Consequently, ablated volume per shot dependence on pulse energy exhibits deviation from linear course. [Copyright &y& Elsevier]

In this work we discuss how sample surface topography can significantly influence the laser ablation (LA) process and, in turn, the analytical response of the LA Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) method. Six different surface topographies were prepared on a certified aluminium alloy sample BAM 311 and SRM NIST 610 to investigate the phenomenon. All the samples were repetitively measured by LA-ICP-MS using a spot by spot analysis. The effect of laser fluence in the range of 1–13 J/cm2 was studied. For majority of measured isotopes, the ICP-MS signal was amplified with roughening of the sample surface. A stronger effect was observed on the Al alloy sample, where the more than sixty-time enhancement was achieved in comparison to the polished surface of the sample. Since the effect of surface topography is different for each analyte, it can be stated that surface properties affect not only the ICP-MS response, but also elemental fractionation in LA. The presented results show that different surface topographies may lead to misleading data interpretation because even when applying ablation preshots, the signal of individual elements changes. The utmost care must be taken when preparing the surface for single shot analysis or chemical mapping. On the other hand, by roughening the sample surface, it is possible to significantly increase the sensitivity of the method for individual analytes and supress a matrix effect. Image 1 • Simple modification of sample surface topography can significantly influence the laser ablation (LA) process. • The ICP-MS response and elemental fractionation enormously differ depending on the surface topography. • Different surface topography may lead to a misleading data interpretation in chemical mapping or single shot analysis. • By roughening the sample surface, it is possible to significantly increase the sensitivity of the LA-ICP-MS. [ABSTRACT FROM AUTHOR]

The method of the laser ablation-inductively coupled plasma-mass spectrometry has become an effective tool in the analysis of the art and archaeological objects. With a few exceptions, however, it has not been fully established in the provenance analysis of historical paintings yet. Although the method is micro-destructive for the paint samples, the direct solid sample analysis with just a minor material removal enables obtaining valuable information on the trace element composition, which is useful for the track the origin of mineral pigments, as, e.g. the clay-based pigments. This work aimed for the optimization of the measurement parameters and a subsequent differentiation of red clays from three reference localities in Europe that were pre-selected based on their relevance for the 18th century painting. Finally, the ground preparatory layer from a painting by an 18th century painter, J. G. de Hamilton, has been analysed. It was satisfactorily proved that the red clay used in the ground was mined out in Troschenreuth, Bavaria, Germany. This is in line with the historical documents recording that Hamilton, when he was acting in Bohemia, bought already primed (ready-to-use) canvases in Bavaria. Despite the heterogeneity and small sizes of paint samples the obtained results show the way in which the provenance analysis of clays in paint samples can be performed. This opens up an entirely new possibility of assessing the regional provenance of historical paintings. Unlabelled Image • LA-ICP-MS methodology optimized for paint micro-samples. • Source locality of natural clays in Baroque grounds revealed. • Possibilities of provenance analysis of paintings extended. [ABSTRACT FROM AUTHOR]