doi:10.1039/c7ja00378aengJiménez-Lamana, J.Abad-Álvaro, I.Bierla, K.Laborda, F.Szpunar, J.Lobinski, R.Detection and characterization of biogenic selenium nanoparticles in selenium-rich yeast by single particle ICPMSART-2018-105328A method based on single particle inductively coupled plasma mass spectrometry (SP-ICPMS) was developed for the analysis of commercial Se-rich yeasts, to confirm the occurrence of selenium nanoparticles in these food supplements. A considerable reduction of background levels was achieved by combining data acquisition at microsecond dwell times and the use of a H2 reaction cell, improving by a factor of 10 the current state-of-the-art methodology, and bringing size detection limits down to 18 nm for selenium nanoparticles. The presence of nanoparticulate selenium was revealed by size-exclusion chromatography ICPMS, with detection of a selenium peak at the exclusion volume of the column showing absorption at a wavelength corresponding to selenium nanoparticles. SP-ICPMS allowed us to confirm the presence of Se-nanoparticles, as well as to calculate the nanoparticle size distribution, from information about the shape and elemental composition of the nanoparticles obtained by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS), respectively. These results reveal the significance of nanoparticles in the speciation of metals and metalloids in biological samples and the capability of SP-ICPMS in combination with TEM-EDS to carry out these analyses.2018http://zaguan.unizar.es/record/7834310.1039/c7ja00378ahttp://zaguan.unizar.es/record/78343oai:zaguan.unizar.es:78343info:eu-repo/grantAgreement/ES/MINECO-FEDER/CTQ2015-68094-C2-1-RJournal of Analytical Atomic Spectrometry 33, 3 (2018), 452-460All rights reservedhttp://www.europeana.eu/rights/rr-f/info:eu-repo/semantics/openAccess