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Background: [ 166 Ho]Ho-acetylacetonate-poly(L-lactic acid) microspheres were used in radioembolization of liver malignancies by intra-arterial administration. The primary aim of this study was to assess the stability and biodistribution of these microspheres., Materials and Methods: Peripheral blood and urine samples were obtained from two clinical studies. Patient and in vitro experiment samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS), gamma-ray spectroscopy, light microscopy, Coulter particle counting, and high performance liquid chromatography (HPLC)., Results: The median percentage holmium compared to the total amount injected into the hepatic artery was 0.19% (range 0.08-2.8%) and 0.32% (range 0.03-1.8%) in the 1 h blood plasma and 24 h urine, respectively. Both the blood plasma and urine were correlated with the neutron irradiation exposure required for [ 166 Ho]Ho-AcAc-PLLA microsphere production (ρ = 0.616, p = 0.002). After a temporary interruption of the phase 2 clinical study, the resuspension medium was replaced to precipitate [ 166 Ho]Ho 3+ pre-administration using phosphate. The in vitro near-maximum neutron irradiation experiments showed significant [ 166 Ho]Ho-AcAc-PLLA microsphere damage., Conclusion: The amount of holmium in the peripheral blood and urine samples after [ 166 Ho]Ho-AcAc-PLLA microsphere intrahepatic infusion was low. A further decrease was observed after reformulation of the resuspension solution but minimization of production damage is necessary., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

Nano-enabled consumer products are a likely source of nanoparticles in the environment and a number of studies have shown the release of nanoparticles from commercial products. Predicted environmental concentrations have been calculated but there is a need for real measurement data to validate these calculations. However, the detection of engineered nanoparticles in environmental matrices is challenging because of the low predicted environmental concentrations which may be in the ng/L range. In this study nanosized Ag, CeO 2 and TiO 2 have been measured in multiple surface water samples collected along the rivers Meuse and IJssel in the Netherlands using single-particle ICP-MS as measurement technique. Validation of the analytical method showed its capability to quantitatively determine nanoparticles at low concentrations. Concentration mass detection limits for Ag, CeO 2 and TiO 2 were 0.1ng/L, 0.05ng/L and 10ng/L respectively. Size detection limits for Ag, CeO 2 and TiO 2 were 14, 10 and 100nm. The results of the study confirm the presence of nano-sized Ag and CeO 2 particles and micro-sized TiO 2 particles in these surface waters. n-Ag was present in all samples in concentrations ranging from 0.3 to 2.5ng/L with an average concentration of 0.8ng/L and an average particle size of 15nm. n-CeO 2 was found in all samples with concentrations ranging from 0.4 to 5.2ng/L with an average concentration of 2.7ng/L and an average particle size of 19nm. Finally, μ-TiO 2 was found in all samples with a concentration ranging from 0.2 to 8.1μg/L with an average concentration of 3.1μg/L and an average particle size of 300nm. The particle sizes that were found are comparable with the particle sizes that are used in nanomaterial applications and consumer products. The nanoparticle concentrations confirm the predicted environmental concentrations values in water for all three nanoparticles., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A new alternative data processing tool set, metAlignID, is developed for automated pre-processing and library-based identification and concentration estimation of target compounds after analysis by comprehensive two-dimensional gas chromatography with mass spectrometric detection. The tool set has been developed for and tested on LECO data. The software is developed to run multi-threaded (one thread per processor core) on a standard PC (personal computer) under different operating systems and is as such capable of processing multiple data sets simultaneously. Raw data files are converted into netCDF (network Common Data Form) format using a fast conversion tool. They are then preprocessed using previously developed algorithms originating from metAlign software. Next, the resulting reduced data files are searched against a user-composed library (derived from user or commercial NIST-compatible libraries) (NIST=National Institute of Standards and Technology) and the identified compounds, including an indicative concentration, are reported in Excel format. Data can be processed batch wise. The overall time needed for conversion together with processing and searching of 30 raw data sets for 560 compounds is routinely within an hour. The screening performance is evaluated for detection of pesticides and contaminants in raw data obtained after analysis of soil and plant samples. Results are compared to the existing data-handling routine based on proprietary software (LECO, ChromaTOF). The developed software tool set, which is freely downloadable at www.metalign.nl, greatly accelerates data-analysis and offers more options for fine-tuning automated identification toward specific application needs. The quality of the results obtained is slightly better than the standard processing and also adds a quantitative estimate. The software tool set in combination with two-dimensional gas chromatography coupled to time-of-flight mass spectrometry shows great potential as a highly-automated and fast multi-residue instrumental screening method., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Since the EFSA enquired a call for data for TBBPA and HBCD in 2009, the analytical determination of these compounds in food became of regulatory interest. Therefore, a method for the simultaneous determination of TBBPA and the three major HBCD stereoisomers was developed. Conventional techniques like soxhlet, ASE, GPC, sulphuric acid digestion, and acidified silica SPE are generally used in sample pre-treatment while detection is mostly performed by LC-MSMS. A combined analysis of HBCD and TBBPA is problematic due to the hydroxyl groups in the TBBPA molecule. However, using a specific mesh-size sodium sulphate in ASE extraction and an acid silica column combined with a Sep-pack Plus silica cartridge for purification resulted in recoveries between 80% and 110% for all compounds. The accuracy and reproducibility determined using proficiency test samples were 104% and 4% for the sum of the HBCD isomers. Typical limits of detection were 0.01 ng/g product or 0.004 ng on column, while the linear dynamic range is between 0.01 ng and 10 ng on column. Levels of TBBPA and HBCD isomers were determined in eel samples. TBBPA was occasionally detected and only marginally above the quantification limit of 0.05 ng/g, whereas total amounts of HBCD were between 0.2 and 150 ng/g with α-HBCD being the dominant HBCD isomer., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A method has been developed for the target analysis of over 100 pesticides and contaminants in a complex feed matrix. The method is based on extraction with ethyl acetate, cleanup by gel permeation chromatography (GPC) and dispersive solid-phase extraction (SPE) with primary secondary amine phase (PSA), and analysis by comprehensive two-dimensional gas chromatography with full scan time-of-flight mass spectrometric detection (GC x GC-TOF-MS). Parameters studied during method development included a dispersive SPE cleanup step after GPC, large volume injection into the GC system and the GC x GC separation. Qualitative and quantitative performance of the GC x GC system was evaluated by analyzing spiked extracts in the range equivalent to 1-100 microg/kg in feed. At levels of 50 microg/kg and higher, all compounds targeted for could be identified fully automatically by the software based on their mass spectra. At lower levels the hit rate decreased with the concentration. System linearity was excellent in solvent and only slightly affected by matrix (correlation coefficients r>or=0.995 for 90% of the compounds). Limits of quantification were in the 1-20 microg/kg range for most compounds. The overall method was validated for 106 compounds at the 10 and 100 microg/kg level. Recoveries between 70% and 110% and RSDs below 20% were obtained for the majority of the compounds.