Open AccessAutomatic implementation of precise grid screens: the four‐corners method
Author(s) -
Hennessy Daniel N.,
Narayanan Beena,
Rosenberg John M.
Publication year - 2009
Publication title -
acta crystallographica section d
Language(s) - English
Resource type - Journals
ISSN - 1399-0047
DOI - 10.1107/s0907444909020320
Subject(s) - grid , computer science , pipette , key (lock) , computational science , simple (philosophy) , computer hardware , distributed computing , computer graphics (images) , chemistry , mathematics , operating system , geometry , philosophy , epistemology
Crystallization trials can be designed as a systematic gradient of the concentration of key reagents and/or pH centered on the original conditions. While the concept of the grid screen is simple, its implementation is tedious and difficult by hand. A procedure has been developed for preparing crystallization grid screens that is both efficient and achieves high accuracy because it relies on a limited number of solutions that are carefully prepared by hand. The `four‐corners' approach to designing grid screens uses the minimum and maximum concentrations of the components being varied in the grid screen as the sole stock solutions. For an N ‐dimensional grid only 2 N corner solutions require detailed preparation, making the screens efficient. Furthermore, by keeping the concentrations as tight as possible to the grid, the potential impact of pipette errors is minimized, creating a highly precise screen.