Detection Limits For Elements Research Articles

Analysis of diluted honey samples from the province of Lower Silesia (Poland) by inductively coupled plasma mass spectrometry

The direct determination of 18 elements (B, Ba, Ca, Cd, Cs, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Rb, Sr, Tl, and Zn) in 1% aqueous honey solutions (dilution factor = 100) by ICP MS was presented. The presence of sugar in sample solutions caused a decrease in analytical signals, the appearance of carbon-containing polyatomic ions, and the deposition of carbonaceous products on a sampler cone. On the flip side, these effects did not destabilize the ICP, while the internal standard calibration (9Be, 89Y, and 153Eu as standards) made it possible to correct matrix effects. Additionally, in the case of 11B, 23Na, 43Ca, and 57Fe isotopes, using a collision cell (He, 2 mL min−1) was required. Due to lower sample blanks, the analysis of water-diluted honey samples offered on average 3 times lower detection limits of elements than achieved for microwave-digested samples. The proposed method, characterized by high analytical throughput, was used for the analysis of 120 samples of honey from the apiaries in the Lower Silesia province. The average content of the major elements in the analyzed honey samples was: B 10.4 mg kg−1, Ca 61.0 mg kg−1, Fe 1.0 mg kg−1, K 1049 mg kg−1, Mg 27.8 mg kg−1, Mn 3.4 mg kg−1, Na 9.1 mg kg−1, Rb 1.4 mg kg−1, Zn 2.0 mg kg−1, and the average content of the trace elements: Ba 130 μg kg−1, Cd 3.2 μg kg−1, Cs 4.8 μg kg−1, Cu 315 μg kg−1, Li 3.8 μg kg−1, Ni 90 μg kg−1, Pb 8.0 μg kg−1, Sr 119 μg kg−1, Tl 1.2 μg kg−1. It was found that (1) the concentrations of all tested elements (except B and Tl) were higher in dark honey, (2) the content of Cs and Rb in honey from the mountain areas of the voivodeship was much higher than this in honey from the lowland areas, and (3) the best discriminators in terms of the color and the botanical origin of honey were the concentrations of Cu and Mn, and to a lesser extent also B, Ca, K, Mg, and Na; e.g., honeydew and buckwheat honey contained much higher amounts of Cu and Mn, sunflower honey was characterized by a significantly higher content of Ca, and rape honey showed an increased B content. Given that the proposed sample preparation procedure allows the simultaneous, reliable, and fast determination of major, trace, and ultra-trace elements, it seems to be a convenient method for the profiling of many honey samples in a very short time.

Blank sample denoising algorithm (BSDA): An effective spectral noise reduction in water sample LIBS detection

Laser-induced breakdown spectroscopy (LIBS), as an elemental composition analysis technique, has many unique advantages and great potential for applications in water detection. However, the quality of LIBS spectral signals, such as signal-to-noise ratio and stability, is often poor due to the matrix effects of water, limiting its practical performance. To effectively remove the inherent weak radiation in experimental spectral data that can be easily mistaken for noise, this paper proposes a denoising algorithm for processing spectral data using a self-built blank sample spectral database of deionized water samples, and designs a complete data processing workflow. It includes steps such as blank sample data screening, internal standard correction, blank sample correction, and spectral smoothing. Against the backdrop of marine applications, experimental spectral data for target elements Na, Mg, Ca, K, Sr, and Li were processed with this algorithm. The results show that after algorithm processing, the spectral quality was significantly improved, with the signal-to-noise ratio and detection limits of various elements improved by at least one order of magnitude. The signal-for Li increased by up to 36 times, and the detection limit for K decreased by up to 25.2 times. Additionally, tiny spectral peaks that could not be observable in the original spectral data could be effectively extracted after processing. From a technical implementation perspective, the database establishment and data process are simple and practical, with universal applicability. Therefore, this method has good potential and wide foregrounds in many other water sample LIBS detection technologies.

Application research of monochromatic micro x‐ray fluorescence in glass physical evidence traceability

AbstractMicro‐x‐ray fluorescence (μ‐XRF) is a commonly used elemental analysis technique for glass physical evidence in forensic cases, which can detect major and trace elements in samples and potentially identify glass fragments according to the differences in elemental composition. However, when a sample is irradiated with polychromatic x‐rays, bremsstrahlung scattering from the source radiation provides noise in the fluorescence spectrum and affects the detection results. To improve the signal‐to‐noise ratio of the fluorescence spectrum, a Mμ‐XRF spectrometer constructed under the low‐power Mo target x‐ray tube condition was used to analyze ten kinds of common glass fragments. The application of laboratory Mμ‐XRF analysis in single‐point detection of tiny glass materials was studied. Experimental results show that the detection limit of Sr element was 51 μg/L, and the spectrometer can distinguish different types of small glass fragments according to the fluorescence spectrum information.

Spectroscopic Analysis of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-COV-2)

Abstract: When light shines on an object, it sheds focus on the intrinsic characteristics of that material. Transmission of light or an electromagnetic (em) wave through a matter undergoes various physiochemical processes, like emission, absorption, and splitting of light into its constituent wavelengths. This interaction of em radiation with matter is widely used for the investigation of unknown and new target analytes in a sample, and the technique is known as spectroscopy. In the early 2000s, energy excitation of the virus was demonstrated in influenza. The research first demonstrated the use of Surface-enhanced Raman Scattering (SERS), whose biomedical application became a potential diagnostic tool. The LASERs also attracted attention and were incorporated with the optical and spectroscopy instruments that significantly enhanced the application, reach, and detection limit of air and waterborne elements. Surface plasmon resonance and SERS are the most applied spectroscopic techniques with high accuracy and speed. A combination of these techniques with other advanced microscopy techniques, such as atomic force microscopy, scanning electron microscopy, and tunnelling electron microscopy, may ease and boost biomedical applications. This review is focused on the application of spectroscopy and laser-based techniques in the detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-COV-2).

Detection of zinc in pig feed based on the cavities of different shapes combined with LIBS

Considering the serious risks posed by the heavy metals present in pig diets, monitoring and controlling the amount of these metals is crucial. The laser-induced breakdown spectroscopy (LIBS) is a promising technique for performing elemental analysis due to its unique advantages, such as rapid, in situ, nondestructive, and online detection of various minerals. In order to improve the detection accuracy and detection limit (LOD) of elements, the spatial constraint combined with laser-induced breakdown spectroscopy (CC-LIBS) is used to detect the quantity of zinc in pig feed and achieve the detection of samples with lower concentrations. Zn I 480.86 nm is selected as the characteristic spectral line, and the effects of different two-dimensional (cylindrical) and three-dimensional (hemispherical, truncated cone) cavities on the enhancement factor are compared under different time delays. The results show that the optimal conditions include a truncated cone cavity D5H3, a delay time of 2.08, and an enhancement factor of 3.01 associated with the analytical spectral line. The detection limit of zinc in samples under CC-LIBS is 62.67 mg/kg (the recommended quantity of zinc in pig diet mentioned in the safe use of feed additives is 43–80 mg/kg), which is 35.65% lower than that under the LIBS (97.39 mg/kg). Therefore, this work provides a new test basis and idea for the detection of zinc in pig feed.

The development and validation of a new method for the fast determination of Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Sr and Zn in rice by inductively coupled plasma optical emission spectrometry.

An alternative method of rice sample preparation for measuring the total content of selected elements, i.e., Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Sr and Zn, by ICP OES was developed. The proposed approach is based on the ultrasound-assisted extraction (USAE) of rice samples in the presence of a small amount of concentrated HNO3. The optimal operating parameters were found using the design of experiments (DOE) approach, and the studied experimental factors were the temperature of the ultrasonic bath (A), the sonication time (B), and the volume of concentrated HNO3 added per 0.5 g of a rice sample (C). Under the optimal conditions of the USAE procedure, i.e., A = 60 °C, B = 16 min and C = 4.0 mL, the rice samples were readily solubilized, and the obtained sample solutions could be analyzed by ICP OES with the simple standard solution calibration (without matrix matching). The analysis of the certified reference material (rice flour, NIST SRM 1568b) confirmed the satisfactory trueness of the USAE-ICP OES method. Additionally, no statistically significant differences between the results obtained for the samples prepared by USAE and open-vessel wet digestion (WD, the reference method) were found. In comparison to the routinely used microwave-assisted digestion and open-vessel digestion, the USAE approach offers lower acid consumption, lower detection limits (LODs) of elements, ranging from 4.0 ng g-1 for Mn to 2.7 µg g-1 for K, and a much shorter time of sample preparation.

Statistical characterization of PIXL trace element detection limits

Trace element detection and mapping are key capabilities of the Planetary Instrument for X-ray Lithochemistry (PIXL) on board the Mars 2020 rover Perseverance. However, poor signal-to-noise ratios due to the short integration times required to make high-spatial-resolution map scans operationally feasible raise the possibility of misidentifying statistical noise as a signal from a trace element, which can cause many false detections of a trace element among the hundreds to thousands of data points in each PIXL scan. Here, we apply a statistical technique to quantify the likelihood of such misidentifications and determine what concentration of a trace element must be present to reach statistical confidence in a detection. This approach is anticipated to be applicable both when analyzing existing PIXL data to ensure that noise is not misinterpreted as signals from trace elements and operationally to inform scan parameters when trace elements of interest are anticipated to be present.

A new full-field XRF imaging station at Synchrotron Light Research Institute.

A full-field X-ray fluorescence imaging (FXI) station was recently developed at beamline BL8 of Synchrotron Light Research Institute (SLRI), Thailand. An unfocused, synchrotron X-ray beam from the bending magnet with a size of 2 mm (vertical) × 13 mm (horizontal) and photon energy of 10 keV was employed in the FXI experiments. A sample stage was tilted by 7.5° to enlarge the vertical beam size. X-ray fluorescence images were recorded by an energy-dispersive, 256 × 256 array, pn-type charge coupled device detector equipped with a polycapillary optics, providing a full-frame image size of 12.3 mm × 12.3 mm. The incident photon flux per pixel was 3 × 104 photons s-1 (100 mA)-1 and the experimental spatial resolution was 68 µm. Image processing was carried out offline using an in-house MATLAB program capable of elemental selection and inhomogeneity intensity correction. Elemental detection limits of FXI were found to decrease with increasing atomic number, i.e. 0.3 to 0.03 wt% for Z = 19 (K) to 30 (Zn). Compared with the BL6b microbeam imaging (µXI) station at SLRI with higher photon flux per pixel, 3 × 1010 photons s-1 (100 mA)-1, a tenfold sample area can be obtained and 13 times higher peak-to-background (PKB) ratio at Zn Kα measured with the same experimental time (8 h). Simultaneous measurement of FXI is more time-efficient against the long overhead times of µXI scanning over large pixel numbers, >65000. To demonstrate potential applications of the new FXI station, various types of samples were examined: dendritic limestone, ancient bronze and dried fish. Analyzed elemental images enabled us to identify areas rich in Mn on the limestone, Sn and Cu separation in the bronze, and Zn nutrition in the dried fish eye.

Phosphate mineralization in leucogranites of the Peshcherninsky stock (Reftinsky massif, Middle Urals)

Relevance. Phosphate mineralization of Devonian intrusions in the Eastern zone of the Middle Urals is currently poorly understood, the data obtained may be important for interpreting the origin of rocks, especially in the case when standard methods of geochemical analysis of rocks do not give a clear picture. Xenotime and monazite are minerals concentrating rare earth elements, and REE distribution graphs are a very important characteristic of rocks. Objective – study of the chemical composition of phosphates in leucogranites of the Peshcherninsky stock. Research methodology. Determination of the chemical composition of the samples was carried out on a Cameca SX100 electron probe microanalyzer at the Common Use Center Geoanalyst, analyst V. A. Bulatov. The analysis was carried out at an accelerating voltage of 15 kV using crystal analyzers TAP, LPC0, LPET, PET, LLIF, LIF. The electron probe current was 10 nA (apatite) and 60 nA (REE, Th phosphates). The pulse accumulation time at the peak maximum was 10 s (for most elements) and 20 s (for REE, Th, U, Pb). During the analysis, on a Cameca SX100 electron probe microanalyzer, the following were used as standards: apatite (for analysis of the content of P, Ca), chlorapatite (Cl), fluorine-phlogopite (F), diopside (Mg, Si), albite (Na, Al), orthoclase (K), rhodonite (Mn), SrSO4 (Sr), TiO2 (Ti), Fe2 O3 (Fe), SrSO4 (Sr), BaSO4 (S), Cr2 O3 (Cr), pyromorphite (Pb) and aluminosilicate glasses doped with REE (La, Ce, Y, Sm, Pr, Nd, Th, U, Tm, Eu, Tb, Dy, Gd, Er, Yb, Lu, Ho). Due to the use of a low probe current in the analysis of apatites, the detection limits for elements were: 300–600 ppm for S, Cl, Al, Mg, Si, Ca, Na and 2000–2500 ppm for P, F, Fe, Mn, Cr. For REE phosphates, the following detection limits were achieved using an increased probe current: 100–200 ppm for Si, Ca, Cr, K, Al, Mg, Ti, Pb, 300–500 ppm for Na, S, P, Mn, Y, Th, U, 1200–1500 ppm for Sr, Nd, Ce, 1700–2000 ppm for La, Tm, Tb, 2500–2800 ppm for Yb, Dy, Lu, Pr, 3500–4700 ppm for Eu, Sm, Gd, Ho. Results. For the first time in Russia, cheralite was found and described in a plutonic rock. The article presents the first data on the chemical composition of phosphates (apatite, monazite, xenotime, cheralite) from the leucogranites of the Pescherninsky stock, which formed at the final stage of the formation of the polychronous and polyformational Reftinsky gabbro-granitoid massif. Conclusion. Apatite belongs to the fluorine variety with an admixture of manganese, monazite is represented by the cerium variety, and xenotime is represented by yttrium. Cheralite has a transitional trace element composition, and depending on the zone, it can be attributed to both cerium and yttrium varieties. The admixture of manganese in apatite may indicate partial mixing of the melt with sedimentary or metasedimentary rocks.

Optimization of an inelastic neutron scattering facility and its application on bulk metallic materials measurement

An inelastic neutron scattering facility consisting of a DT neutron generator and a HPGe detector was used for metallic material analysis. The facility model was optimized based on Monte Carlo simulations. Performance of modified facility was tested through various metallic elements measurements. The results showed that the mass detection limits (MDL) of different elements were improved after optimization. Quantitative analyses of Fe and Cr in stainless steel sample were then conducted to evaluate the performance of alloy measurement. Calibration curves were obtained through measuring the reference samples. The contents of Fe and Cr in an unknown sample were determined by the calibration curves and the results were in good agreement with those obtained by X-ray fluorescence method.

Metal micro/nanostructure enhanced laser-induced breakdown spectroscopy

This study used a femtosecond laser to ablate a Cu sample, forming a micro/nanostructural layer on the surface. And the effect of this structural layer on nanosecond laser-induced breakdown spectroscopy (LIBS) was discussed. Firstly, the effect of the micro/nanostructural layer on the intensity of laser-induced Cu plasma spectra was investigated. The micro/nanostructure could significantly enhance the spectral intensity of the Cu plasma by 82.5 times at 13.3 mJ laser energy. Secondly, the Cu plasma temperature and electron density were calculated. The micro/nanostructures could significantly increase Cu plasma temperature and electron density. Finally, the effect of micro/nanostructure surface on the spectral intensities of Pb and Cr elements in water was investigated for LIBS analysis. It was found that the detection limit of Pb and Cr trace metal elements in water was 1.85 ng/mL and 0.51 ng/mL at a lower laser energy (13.3 mJ), which was significantly better than other LIBS methods reported so far. The results show that the micro/nanostructure enhanced LIBS is a more sensitive method for detecting trace metal elements in the water.

Inductively Coupled Plasma-Tandem Mass Spectrometry (ICP-MS/MS) and Its Applications

During the last about 10 years, the inductively coupled plasma tandem quadrupole mass spectrometry (ICP-MS/MS) technique with reaction cell is being utilized for the analyses of several trace elements/isotopes at very low concentration levels in a variety of matrices including geological, environmental, biological, medical, nuclear, agriculture, food, material and metallurgical sciences. Both solution nebulization, as well as direct analysis of samples by laser ablation (LA-ICP-MS/MS), are utilized for sample introduction. In fact, ICP-MS/MS technique with collision reaction cells eliminated the need for laborious chemical separations using methods such as ion-exchange or solvent extraction procedures to eliminate/minimize spectral and matrix interference effects as these interferences are removed using online chemical reactions within the instrument itself (chemical resolution). In addition, the technique is hyphenated with chromatographic techniques such as GC and HPLCfor a variety of applications. The detection limits for several elements in the periodic table lie in the pg/ml-fg/ml range, and the technique compares favourably with the expensive, complex, and superior high resolution-ICP-MS (HR-ICP-MS), both in terms of the detection limits as well as the ability to remove the most complex interferences. Thus, the ICP MS/MS made the determinations of elemental as well as isotopic concentrations very simple andeasy even in complex materials with several novel quantification approaches. This article provides an overview of these new developments during the last decade along with several applications in all areas of science and technology.

Inductively Coupled Plasma-Tandem Mass Spectrometry (ICP-MS/MS) and Its Applications

During the last about 10 years, the inductively coupled plasma tandem quadrupole mass spectrometry (ICP-MS/MS) technique with reaction cell is being utilized for the analyses of several trace elements/isotopes at very low concentration levels in a variety of matrices including geological, environmental, biological, medical, nuclear, agriculture, food, material and metallurgical sciences. Both solution nebulization, as well as direct analysis of samples by laser ablation (LA-ICP-MS/MS), are utilized for sample introduction. In fact, ICP-MS/MS technique with collision reaction cells eliminated the need for laborious chemical separations using methods such as ion-exchange or solvent extraction procedures to eliminate/minimize spectral and matrix interference effects as these interferences are removed using online chemical reactions within the instrument itself (chemical resolution). In addition, the technique is hyphenated with chromatographic techniques such as GC and HPLCfor a variety of applications. The detection limits for several elements in the periodic table lie in the pg/ml-fg/ml range, and the technique compares favourably with the expensive, complex, and superior high resolution-ICP-MS (HR-ICP-MS), both in terms of the detection limits as well as the ability to remove the most complex interferences. Thus, the ICP MS/MS made the determinations of elemental as well as isotopic concentrations very simple andeasy even in complex materials with several novel quantification approaches. This article provides an overview of these new developments during the last decade along with several applications in all areas of science and technology.

Improvement of limit of detection sensitivities in the parts per billion range using conventional geometry synchrotron radiation excited EDXRF measurements

The use of a thin polymer foil as a sample carrier in the EDXRF technique may provide elemental detection limits comparable to the TXRF technique.

Microanalysis using secondary ion emission By Raimond Castaing and Georges Slodzian

Secondary ion mass spectrometry (SIMS) is an analytical technique used to probe the composition of solids through the sputtering of the sample with a focussed primary ion beam and analyzing the emitted secondary ions generated under impact. These secondary ions ranging from elementals to low molecular weight organics offer precious information on the molecular composition and spatial organization within samples. Today, the combination of modern SIMS methodologies and instrumentation offers the most sensitive surface analysis approach, with elemental detection limits ranging from parts per million to parts per billion. In this month’s special feature article, we retrace the steps taken by Raimond Castaing and Georges Slodzian who in the early 1960’s developed a SIMS instrument based on a magnetic double focusing sector field mass spectrometer and using argon for the primary ion beam. This seminal work was first published in 1962, in French, in the Journal de Microscopie, which limited access to the scientific community at large. This article is now available in English and is beautifully prefaced by Georges Slodzian who revisits his steps as a young graduate student in the Castaing laboratory and discusses the scientific legacy of this article in the development of modern SIMS instrumentation.

Application of non-stationary phase separation hyphenated with inductively coupled plasma mass spectrometry in the analysis of trace metal-containing nanoparticles in the environment

环境中金属纳米颗粒的分析检测不仅需要关注其浓度和化学组成,还需要对其形状、粒径和表面电荷等进行表征。此外,环境中金属纳米颗粒的分析需要解决其低赋存浓度以及复杂基质干扰的难题。无固定相分离技术与电感耦合等离子体质谱(ICP-MS)的在线联用,具有较强的颗粒分离能力和较低的元素检出限,能够快速准确地提供金属纳米颗粒的粒径分布、化学组成等信息,在金属纳米颗粒的分离检测方面表现出极大的潜能。但这一联用技术尚无法获得金属纳米颗粒物的颗粒数浓度和单个颗粒的元素信息,难以判断金属纳米颗粒涂层厚度、纯度以及颗粒的均相/异相团聚行为等。新兴的单颗粒-电感耦合等离子体质谱(SP-ICP-MS)与无固定相分离技术的在线联用,可以获得金属纳米颗粒的流体动力学粒径、元素质量计算粒径和颗粒数浓度等信息,进而弥补无固定相分离与ICP-MS在线联用技术的不足。该文介绍了流体动力色谱、毛细管电泳和场流分离3种常用无固定相分离技术的分离机制和适用检测器,着重综述了无固定相分离技术与ICP-MS/SP-ICP-MS在线联用技术的特点及其在环境金属纳米颗粒分析中的应用。关于场流分离,主要介绍了可以与ICP-MS联用的沉降场流分离和流场流分离。该文还对流体动力色谱、毛细管电泳和流场流分离与ICP-MS在线联用技术的特点进行了比较。最后,该文对无固定相分离技术与ICP-MS/SP-ICP-MS在线联用技术的发展提出了展望。

Analyses of Li-Rich Minerals Using Handheld LIBS Tool

Lithium (Li) is one of the latest metals to be added to the list of critical materials in Europe and, thus, lithium exploration in Europe has become a necessity to guarantee its mid- to long-term stable supply. Laser-induced breakdown spectroscopy (LIBS) is a powerful analysis technique that allows for simultaneous multi-elemental analysis with an excellent coverage of light elements (Z < 13). This data paper provides more than 4000 LIBS spectra obtained using a handheld LIBS tool on approximately 140 Li-content materials (minerals, powder pellets, and rocks) and their Li concentrations. The high resolution of the spectrometers combined with the low detection limits for light elements make the LIBS technique a powerful option to detect Li and trace elements of first interest, such as Be, Cs, F, and Rb. The LIBS spectra dataset combined with the Li content dataset can be used to obtain quantitative estimation of Li in Li-rich matrices. This paper can be utilized as technical and spectroscopic support for Li detection in the field using a portable LIBS instrument.

Energy dispersive X‐ray fluorescence methodology and analysis of suspended particulate matter in seawater for trace element compositions and an intercomparison with high‐resolution inductively coupled plasma‐mass spectrometry

AbstractA modification of energy dispersive X‐ray fluorescence (ED‐XRF) for analysis of trace element concentrations in suspended particulate matter (SPM) in seawater and intercomparison with high‐resolution inductively coupled plasma‐mass spectrometry (HR ICP‐MS) is presented. Approximately 250 SPM samples were collected on polycarbonate track‐etched filters in the Indian Ocean during the U.S. CLIVAR/CO2 Repeat Hydrography meridional section I09N cruise in 2007. Samples were first analyzed by ED‐XRF, a nondestructive technique, for Al, P, Ti, Mn, Fe, Ni, Cu, and Zn and subsequently digested and quantified by HR ICP‐MS, creating two blind, basin‐scale data sets used for a paired statistical comparison. Our results found (1) ED‐XRF analysis using thin‐film principles can quantify the elemental composition of SPM at nanomolar concentrations found in the open ocean; (2) there was excellent agreement between ED‐XRF and HR ICP‐MS analyses for Al, Fe, and Mn and good agreement for P and Ti; (3) analytical differences were the largest for Cu, Ni, and Zn; (4) HR ICP‐MS methods have lower detection limits for most elements when compared to the ED‐XRF; (5) ED‐XRF analysis has a closer agreement to reported values for the NIST SRM 2783 standard and lower relative standard deviations when compared to the HR ICP‐MS. We recommend continued refinement of nondestructive ED‐XRF methods as this would allow for the easy exchange of filtered samples between lab groups for intercalibration and intercomparison of basin‐scale hydrographic cruises and archival for future analysis.

The assessment of the usability of selected instrumental techniques for the elemental analysis of biomedical samples

The fundamental role of major, minor and trace elements in different physiological and pathological processes occurring in living organism makes that elemental analysis of biomedical samples becomes more and more popular issue. The most often used tools for analysis of the elemental composition of biological samples include Flame and Graphite Furnace Atomic Absorption Spectroscopy (F-AAS and GF-AAS), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Each of these techniques has many advantages and limitations that should be considered in the first stage of planning the measurement procedure. Their reliability can be checked in the validation process and the precision, trueness and detection limits of elements belong to the most frequently determined validation parameters. The main purpose of this paper was the discussion of selected instrumental techniques (F-AAS, GF-AAS, ICP-OES and ICP-MS) in term of the achieved validation parameters and the usefulness in the analysis of biological samples. The focus in the detailed literature studies was also put on the methods of preparation of the biomedical samples. What is more based on the own data the usefulness of the total reflection X-ray fluorescence spectroscopy for the elemental analysis of animal tissues was examined. The detection limits of elements, precision and trueness for the technique were determined and compared with the literature data concerning other of the discussed techniques of elemental analysis. Reassuming, the following paper is to serve as a guide and comprehensive source of information concerning the validation parameters achievable in different instrumental techniques used for the elemental analysis of biomedical samples.

Rapid quantitative analysis of trace elements in plutonium alloys using a handheld laser-induced breakdown spectroscopy (LIBS) device coupled with chemometrics and machine learning.

We present the first reported quantification of trace elements in plutonium via a portable laser-induced breakdown spectroscopy (LIBS) device and demonstrate the use of chemometric analysis to enhance the handheld device's sensitivity and precision. Quantification of trace elements such as iron and nickel in plutonium metal via LIBS is a challenging problem due to the complex nature of the plutonium optical emission spectra. While rapid analysis of plutonium alloys has been demonstrated using portable LIBS devices, such as the SciAps Z300, their detection limits for trace elements are severely constrained by their achievable pulse power and length, light collection optics, and detectors. In this paper, analytical methods are evaluated as a means to circumvent the detection constraints. Three chemometric methods often used in analytical spectroscopy are evaluated; principal component regression, partial least-squares regression, and artificial neural networks. These models are evaluated based on goodness-of-fit metrics, root mean-squared error, and their achievable limits of detection (LoDs). Partial least squares proved superior for determining content of iron and nickel in plutonium metal, yielding LoDs of 15 and 20 ppm, respectively. These results of identifying the undesirable trace elements in plutonium components are critical for applications such as fabricating radioisotope thermoelectric generators or nuclear fuel.