Hangman: a macromolecular hanging-drop vapor-diffusion technique

A modification of the hanging-drop vapor-diffusion technique is presented, which uses an adhesive surface to simultaneously support the protein solution for crystallization and form an airtight seal with the reservoir solution. The hanging-drop vapor-diffusion technique is an efficient means of screening crystallization parameters which offers the advantage of a very small minimum droplet volume, as low as 2μl per experiment. Screening and optimization of parameters with a minimal amount of sample can thus be accomplished. Two inefficiencies in the hanging-drop experiment are the time and cost involved in silicone treatment, cleaning and polishing glass coverslips and treatment of the Linbro tissue culture plates with grease or oil to form an airtight seal with the coverslips.