TY - JOUR A1 - Lopez-Serrano Oliver, Ana A1 - Haase, A. A1 - Peddinghaus, A. A1 - Wittke, D. A1 - Jakubowski, Norbert A1 - Luch, A. A1 - Grützkau, A. A1 - Baumgart, S. T1 - Mass cytometry enabling absolute and fast quantification of silver nanoparticle uptake at the single cell level N2 - In the last decades, significant efforts have been made to investigate possible cytotoxic effects of metallic nanoparticles (NPs). Methodologies enabling precise information regarding uptake and intracellular distribution of NPs at the single cell level remain to be established. Mass cytometry (MC) has been developed for high-dimensional single cell analyses and is a promising tool to quantify NP−cell interactions. Here, we aim to establish a new MC-based quantification procedure to receive absolute numbers of NPs per single cell by using a calibration that considers the specific transmission efficiency (TE) of suspended NPs. The current MC-quantification strategy accept TE values of complementary metal solutions. In this study, we demonstrate the different transmission behavior of 50 nm silver NPs (AgNP) and silver nitrate solution. We have used identical AgNPs for calibration as for in vitro-differentiated macrophages (THP-1 cell line) in a time- and dose-dependent manner. Our quantification relies on silver intensities measuring AgNPs in the same detection mode as the cells. Results were comparable with the TE quantification strategy using AgNPs but differed when using ionic silver. Furthermore, intact and digested cell aliquots were measured to investigate the impact of MC sample processing on the amount of AgNPs/cell. Taken together, we have provided a MC-specific calibration procedure to precisely calculate absolute numbers of NPs per single cell. Combined with its unique feature of multiplexing up to 50 parameters, MC provides much more information on the single cell level than single cell-inductively coupled plasma mass spectrometry (SC-ICP-MS) and, therefore, offers new opportunities in nanotoxicology. KW - ICP-MS KW - Nanoparticle KW - Cell KW - SC-ICP-MS KW - Mass cytometry PY - 2019 U6 - https://doi.org/10.1021/acs.analchem.9b01870 SN - 0003-2700 SN - 1520-6882 VL - 91 IS - 18 SP - 11514 EP - 11519 PB - American Chemical Society (ACS Publications) CY - Washington AN - OPUS4-48986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - López-Serrano Oliver, Ana A1 - Baumgart, S. A1 - Bremser, Wolfram A1 - Flemig, Sabine A1 - Wittke, D. A1 - Grützkau, A. A1 - Luch, A. A1 - Haase, A. A1 - Jakubowski, Norbert T1 - Quantification of silver nanoparticles taken up by single cells using inductively coupled plasma mass spectrometry in the single cell measurement mode N2 - The impact of nanoparticles, NPs, at the single cell level has become a major field of toxicological research and different analytical methodologies are being investigated to obtain biological and toxicological information to better understand the mechanisms of cell–NP interactions. Here, inductively coupled plasma mass spectrometry in the single cell measurement mode (SC-ICP-MS) is proposed to study the uptake of silver NPs, AgNPs, with a diameter of 50 nm by human THP-1 monocytes in a proof-ofprinciple experiment. The main operating parameters of SC-ICP-MS have been optimized and applied for subsequent quantitative analysis of AgNPs to determine the number of particles in individual cells using AgNP suspensions for calibration. THP-1 cells were incubated with AgNP suspensions with concentrations of 0.1 and 1 µg/mL for 4 and 24 hours. The results reveal that the AgNP uptake by THP-1 monocytes is minimal at the lower dose of 0.1 µg/mL (roughly 1 AgNP per cell was determined), whereas a large cell-to-cell variance dependent on the exposure time is observed for a 10 times higher concentration (roughly 7 AgNPs per cell). The method was further applied to monitor the AgNP uptake by THP-1 cells differentiated macrophages incubated at the same AgNP concentration levels and exposure times demonstrating a much higher AgNP uptake (roughly from 9 to 45 AgNPs per cell) that was dependent on exposure concentration and remained constant over time. The results have been compared and validated by sample digestion followed by ICP-MS analysis as well as with other alternative promising techniques providing single cell analysis. KW - Silbernanopartikel KW - ICP-MS KW - Einzelzellanalyse PY - 2018 U6 - https://doi.org/10.1039/C7JA00395A SN - 0267-9477 VL - 33 IS - 7 SP - 1256 EP - 1263 PB - Royal Society of Chemistry CY - London AN - OPUS4-45473 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -