Difference: InsertCryoSample (3 vs. 4)

Cryo sample loading

Contents

Apertures

• Condenser aperture #2
• Objective aperture #4

Check for beam before loading sample

• Insert specimen holder to first stop
• In setup menu "open column valves"
• If no beam lower magnification
• In low dose menu Lexposure mode, spot size should read 2 if not reload good configuration (i.e. JB1) save as your own
• Check alignment of scope before inserting sample

Loading cryo sample into holder

• Reset holder
• Set holder alpha value to -79
• Top off LN2 in cold trap
• Retrieve sample
• Practice removing clip w/o LN2
• Cool down sample dewer and sample loading end (fill about ½ with LN2)
• After boiling subsides top off
• Remove grid
• Place in holder
• Replace clip ring
• Press firm with sample tap
  • Keep 2mm of LN2 covering sample at all times

Loading cryo holder into scope

• Insert sample to first stop (do not let go until vacuum kicks in)
• Identify holder at the bottom of the screen
• When light goes out, push Reset holder
• Hold sample turn upright and insert slowly
• Top off dewar
• Clear with blow off pipe to calm LN2
• Cover Dewar
• Wait one hour before imaging to achieve equilibrium temperature with no gradients

Finally

• Open shutter and move sample to make sure vacuum does not fluctuate before opening column valves

Visit Cryo EM Web site at http://www.nysbc.org/facilities/CEM

-- DavidStokes - 18 Mar 2005

• Set ALLOWTOPICCHANGE = CemfacGroup