Quantifying the quality of the experiments used to grow protein crystals: theiQCsuite
Millions of crystallization trials are set up each year, with no clear metrics for determining if the experiments were correctly dispensed. This article reports the development of a software tool (iQC–image Quality Control) that recognizes factors associated with suboptimal experimental control during the setting up of protein crystallization trials. In its simplest form,iQCreturns a report that gives an overall rating to the quality of an experimental setup. TheiQCsoftware is able to identify many common problems observed in setting up crystallization trials – droplets that have associated splatter; droplets with air bubbles; the positional accuracy of droplet placement; elongated or otherwise `non-circular' drops – as well as detecting small and large droplets. An obvious use of this application is to track the status of the instrumentation used to set up crystallization trials in a multi-user laboratory.