$salt crystal diffraction pattern$

$salt crystal diffraction pattern$

Salt crystal diffraction pattern trial#

A crunchy crystal is likely to be salt a soft crystal is likely to be a macromolecule. In the ‘crush test’ the crystal is poked with a fine-tipped glass rod.

Salt crystal diffraction pattern trial#

Thus, alternative tests to show that crystals are made of protein are needed to establish whether the results of a crystallization trial merit further study.

$salt crystal diffraction pattern$

In addition, the initial crystals may be small or of poor quality or may become damaged during harvesting or other handling. However, access to an X-ray beam may not be available without significant expense and delay. Specialized equipment such as the PX Scanner (Oxford Diffraction) allows this to be performed in situ. A direct and definitive test is to simply mount the crystal in an X-ray beam and take an image of the diffraction pattern. However, each individual method has limits to its application or may possibly yield misleading results. Several methods can be used to determine whether a crystal is composed of salt or a macromolecule (Jordanova et al., 2008 ▶). Unfortunately, salt crystals are often encountered in these screens. The path to obtaining an X-ray crystal structure usually starts with systematic trials of solution conditions, pathways to equilibrium, protein concentrations and incubation temperatures. The growth of crystals is a major bottleneck for the crystallography of macromolecules.

$salt crystal diffraction pattern$