Gatan ultrascan 1000 ccd camera

For scanning electron microscopy (SEM), cells were processed as published [10 (link)]. For transmission electron microscopy (TEM), samples were fixed in 2% PFA/2.5% glutaraldehyde for 1 h, post-fixed in cacodylate buffer/OsO4 for 1 h, and afterwards washed in cacodylate buffer. After dehydration, samples were infiltrated (propylene oxide and TAAB embedding resin, pure TAAB embedding resin) for 3 h, placed in TAAB embedding resin (2x 90 min), transferred into embedding molds, and polymerized (72 h, 60 °C). Sections were stained with lead citrate and platinum blue (International Bio-Analytical Industries, Inc., Boca Raton, FL, USA), and investigated at 120 kV with a Tecnai G 2 FEI microscope (FEI, Eindhoven, Netherlands) equipped with a Gatan ultrascan 1000 CCD camera.

Five microliters of postprandial lymph and plasma chylomicrons from HF/HCD-fed mice were subjected to freeze-fracture transmission electron microscopy as described previously [20 (link)]. Images were taken using a FEI Tecnai G2 20 transmission electron microscope (FEI, Eindhoven, The Netherlands) with a Gatan ultrascan 1000 CCD camera. Acceleration voltage was 120 kV. Particle size distribution of 100–200 particles from 18 electron micrographs was estimated using Image J software (ImageJ 1.43U, NIH, USA).

AuPEI were characterized by cryogenic transmission electron microscopy (cryo-TEM) as published elsewhere [48 (link)]. A 4 µL droplet of particle aqueous solution was deposited on a Quantifoil^® (Quantifoil Micro Tools GmbH, Großlöbichau, Germany) holey carbon grid. The excess of liquid on the grid was absorbed with a filter paper, and the grid was quench-frozen quickly in liquid ethane to form a thin vitreous ice film. Once placed in a Gatan 626 cryo-holder cooled with liquid nitrogen, the samples were transferred to the microscope and observed at low temperature (−180 °C). Cryo-TEM images were recorded with a 2 k × 2 k Gatan Ultrascan 1000 CCD camera (Gatan, Pleasanton, CA, USA), using a LaB₆ JEOL JEM2100 (JEOL, Tokyo, Japan) cryo-microscope operating at 200kV. Images were taken with the JEOL low-dose system (Minimum Dose System, MDS) to protect the thin ice film from any irradiation before imaging and reduce the irradiation during the image capture (IMPMC, Sorbonne Université, 4 place Jussieu, Paris 75005, France).