Detailed knowledge of protein structures has a high value in many scientific aspects. One of the most effective techniques for determining protein structures is X-ray crystallography, which requires high-quality mono-crystals of the investigated macromolecule. Obtaining such crystals is an empirical process and a crucial step on the way to structure determination.

If for any reason crystallization of the protein is not possible or wanted, the structure can be determined with Cryo-Electron Microscopy (cryo-EM) and Single Particle Analysis (SPA). For those techniques, sample preparation is most important and determines the success of the experiment.