TY - JOUR A1 - Shigeta, K. A1 - Traub, Heike A1 - Panne, Ulrich A1 - Okino, A. A1 - Rottmann, L. A1 - Jakubowski, Norbert T1 - Application of a micro-droplet generator for an ICP-sector field mass spectrometer - optimization and analytical characterization N2 - A micro-droplet generator (µDG) sample introduction system was coupled to a sector field ICP-MS instrument to investigate the analytical figures of merit with respect to single cell analysis. The sector field instrument was operated for the first time in a fast scanning mode (E-scan) with the shortest time resolution of 100 µs to measure the single droplet time resolved and using the original detector in a pulse counting mode without modification of the existing electronics. For reduction of the droplet diameter a triple pulse mode of the droplet generator was applied and a droplet diameter down to 23 µm has been achieved for this investigation with a 100% transport efficiency of droplets. Signal duration times of single droplets of less than 500 µs have been measured. Overall detection efficiencies in the range of 10-3 counts per atom have been achieved and absolute limits of detection range between 120 ag for Fe and 1.1 ag for Mg as a mean value from 1000 droplet events. PY - 2013 U6 - https://doi.org/10.1039/c2ja30207a SN - 0267-9477 SN - 1364-5544 VL - 28 IS - 5 SP - 646 EP - 656 PB - Royal Society of Chemistry CY - London AN - OPUS4-29447 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Shigeta, K. A1 - Koellensperger, G. A1 - Rampler, E. A1 - Traub, Heike A1 - Rottmann, L. A1 - Panne, Ulrich A1 - Okino, A. A1 - Jakubowski, Norbert T1 - Sample introduction of single selenized yeast cells (Saccharomyces cerevisiae) by micro droplet generation into an ICP-sector field mass spectrometer for label-free detection of trace elements N2 - We have applied a micro droplet generator (µDG) for sample introduction of single selenized yeast cells into a sector field ICP-MS, which was operated in a fast scanning mode with sampling rates of up to 10 kHz, to measure single cells time resolved with 100 µs integration time. Selenized yeast cells have been used as a model system for preliminary investigation. The single cells to be measured have been embedded into droplets and it will be shown that the time duration of a single cell event always is about 400 to 500 µs, and thus comparable to the time duration of a droplet without a cell. A fixed droplet generation rate of 50 Hz produced equidistant signals in time of each droplet event and was advantageous to separate contribution from background and blank from the analytical signal. Open vessel digestion and a multielement analysis were performed with washed yeast cells and absolute amounts per single cell were determined for Na (0.91 fg), Mg (9.4 fg), Fe (5.9 fg), Cu (0.54 fg), Zn (1.2 fg) and Se (72 fg). Signal intensities from single cells have been measured for the elements Cu, Zn and Se, and histograms were calculated for about 1000 cell events. The mean elemental sensitivities measured here range from 0.7 counts per ag (Se) to 10 counts per ag (Zn) with RSD's from 49% (Zn) to 69% (Se) for about 1000 cell events. PY - 2013 U6 - https://doi.org/10.1039/c3ja30370e SN - 0267-9477 SN - 1364-5544 VL - 28 IS - 5 SP - 637 EP - 645 PB - Royal Society of Chemistry CY - London AN - OPUS4-29448 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -