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, Freeze substitution 1. Screw top 2 mL tubes (SARDTEDT, catalog number: 72.693) 2. Disposable regular pipettes 1, 2 and 3 mL (VWR, catalog number: 612-2850, 612-2851 and 612-1681) and Freeze Substitution specific 1 mL pipettes with thin tips (Ratiolab, p.2600155

, Wheaton glass sample vials with snap-cap for cryomix preparation (DWK Life Sciences, WHEATON, catalog number: 225536.) 4. Personal cartridge half mask 6100 (Honeywell International, catalog number: 1029471) 5. Aluminum foil 6. Uranyl acetate powder (Merck, p.8473

, Pure methanol

, Ultra-pure 100 % ethanol and acetone (VWR, catalog numbers: 83813.440 and, vol.558, 20066.

, Colored nail polish (color does not matter)

, Leica microsystems, catalog number: 16707158) 11. Cryosubstitution Uranyl-acetate stock solution (20 %) (see Recipe 4) 12. Cryosubstitution mix (see Recipe 5) 13. HM20 resin (Electron Microscopy Sciences, catalog number 14345) 14. HM20% solutions (see recipe 6) 15. Reagent bath (Leica microsystems, catalog number: 16707154) 16. Plastic mold 'Flow-through rings

E. Ultramicrotomy, Crystalizing dish (Fisher Scientific, catalog number: 11766582) Manufacturer: DWK Life Sciences, DURAN, catalog number: 213133408. 2. Fast absorbent paper filters (Whatman, Filter papers 41) (GE Healthcare, vol.1, pp.1441-070

, Glass rods (Fisher Scientific, catalog number: 12441627) Manufacturer: MBL, catalog number: SRF380

, Grids with 200 L/inch square mesh Fine Bar (Electron Microscopy Sciences, catalog number: G200HS-Cu) to coat with parlodion or commercial grids with formvar (Electron Microscopy Sciences, p.200

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