Prepare a seed stock

• Wash several crystals to remove amorphous precipitate
• Stabilize the crystals
• suspend the crystals in a non-dissolving precipitant solution (usually 10% above the reservoir precipitant concentration)
• work at a temperature that does not dissolve the crystals.
• Crush the crystals in a glass homogenizer
• This seed stock can be stored at constant temperature for later use

Serial dilution

• Perform serial dilutions of the seeds to give final dilutions of 1 in 1000 to 1 in 10,000,000
• Dilute using the stabilizing precipitant solution.

Seeding

• Streakseed preequilibrated drops using seeds from different dilutions
• Add a drop of seeds from different dilutions
• If nucleation is independent of the dilution, the precipitant concentration in the seeds solutions should be lowered
• If there is a sudden decrease in the number of crystals obtained, increase the precipitant concentration in the seeds

© 1999-2005 Airlie J McCoy, University of Cambridge. All rights reserved.

Last updated: 7 June, 2005