Dark current spectroscopy of transition metals in CMOS image sensors

We have investigated the effects of deliberate heavymetals contamination on dark current and image defects in CMOS Image Sensors (CIS). Analysis of dark current in these imager dice has revealed different behaviors among most important 3d metals present in the process line. We have implanted directly in 3 Mega array pixels the following metals: Cr, V, Cu, Ni, Fe, Ti, Mo, W, Al and Zn. Analyzing the dark current "spectrum" as obtained for fixed integration periods of time by means of standard image-Testing equipment, these impurities can be identified and detected with a sensitivity of ∼ 109 traps/cm3 or higher

Engineered Extracellular Vesicles for biogenesis and immunomodulation studies

Small Extracellular Vesicles (sEV), as naturally occurring vesicles, have a low intrinsic immunogenic profile, thus showing great therapeutic potential. Over the past few years, several engineering strategies have been devised to manipulate tumor-derived sEVs in order to induce cellular and innate immunity. In our study we use a mutant Human Immunodeficiency Virus (HIV)-1 Nef protein that presents a N-terminal palmitoylation (NefG3C), which increase the specificity of the protein for sEV association and a mutated NefG3C with two additional mutations (Nefmut) to render the protein biologically inactive. Both Nef mutants were fused at C-terminus with Green Fluorescent Protein (GFP) (NefG3C/Nefmut-GFP). To follow the biogenesis of these engineered sEV we used a novel methodology developed in our laboratory to metabolically label exosomes by incubating cells with a red fluorescent fatty acid BODIPY 558/568 C12 (C12). The lipid is readily taken up by cells and transformed into phospholipids that will ultimately form the exosome lipid bilayer. By transfecting HEK293 cells with the NefG3C-GFP or Nefmut-GFP vectors and pulsing them with C12 we could purify exosomes containing NefG3C/mut-GFP and/or C12 (C12 exo). Results show that the number of cell secreted sEV greatly differs for the two constructs probably due to a different association with sEV. Fluorescent sEV were also characterized for typical exosomes markers and analyzed in iodixanol density gradients. NefG3C/Nefmut-GFP/C12 exo could be separated in two distinct peaks whereas C12 exo displayed only one fluorescent peak. Further analysis will show if these two different populations of sEV display different behaviour in terms of efficiency of transfer to recipient cells and ultimately stimulation of the immune system

Highly Sensitive Detection of Inorganic Contamination

As the detection of inorganic contaminants is of steadily increasing importance for the improvement of yields in microelectronic applications, the aim of one of the joint research activity within the European Integrated Activity of Excellence and Networking for Nano- and Micro-Electronics Analysis (ANNA, site: www.ANNA-i3.org) is the development and assessment of new methodologies and metrologies for the detection of low concentration inorganic contaminants in silicon and in novel materials. A main objective consist in the benchmarking of various analytical techniques available in the laboratories of the participating ANNA partners, including the improvement of the respective detection limits as well as the quantitation reliablity of selected analytical techniques such as total-reflection x-ray fluorescence (TXRF) analysi