Macroseeding is used to enlarge crystals for X-ray data collection under condition of lower supersaturation than required for spontaneous nucleation or for the analytical use of streak seeding

The figure illustrates the various washes that are needed in the use of this technique. For a more comprehensive view of the method see:

20. Stura E.A., Wilson I.A. (1991) Seeding Techniques. In ``Crystallization of Nucleic Acids and Proteins: a practical approach'' (A. Ducruix and G.Giegé eds.) IRL Press, Oxford, pp. 241-254.

Abstract: A seed provides a template for the assembly of molecules to form a crystal with the same characteristics as the crystal from which the seed originated. Seeding has often been used as a method of last resort, rather than a standard practice. It has been used in situations when, after the first crystallization event, further attempts at crystallizing the same or subsequent batches of the same protein under apparently identical crystallization conditions, either failed to yield any crystals at all, provided crystalline precipitates or very small crystals. The use of seeding in crystallization can simplify the task of the crystallographer even when crystals can be obtained by other means. We will explore the various seeding techniques, and their applications, in the growth of large single crystals.

A new edition will be coming to press in 1997. It is a text book well worth having.

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