Methods of Protein Crystallization

Vapour Diffusion Experiment

In a vapour diffusion experiment, small volumes of precipitant and protein mixed together and the drop equilibrated against a larger reservoir of solution containing precipitant or another dehydrating agent.

Phase diagram for vapour diffusion

Hanging Drop

Trays for hanging drop experiments Coverslips Greasing

Sitting Drop
Trays for sitting drop experiments Coverslips or Tape

Sandwich Drop
Trays for sandwich drops
  • Q-Plate from Hampton and Molecular Dimensions                                                                                                               
Coverslips or Tape as above

Batch Experiment

In batch crystallization the precipitant and protein are mixed directly under oil.

Phase diagram for batch experiment
Trays for batch experiments For more information see Douglas Instrument's Research Papers.


In a dialysis crystallization experiment, protein is equilibrated against a larger volume of precipitant through a dialysis membrane.

Phase diagram for dialysis experiment
Dialysis buttons are available from Hampton

Trays for dialysis as for hanging drop

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

Last updated: 7 June, 2005