Design, 3D printing and validation of a novel low-cost high-capacity sitting-drop bridge for protein crystallization

Abstract

Sitting-drop protein crystallization is not used as commonly as the hanging-drop method for crystal optimization owing to the limitations of commercially available sitting-drop bridges, particularly when they are used in conjunction with 24-well crystallization plates. The commercially available sitting-drop bridge, containing space for only a single drop, restricts their wider use. Proteins that preferentially crystallize under sitting-drop conditions therefore require more work, time and resources for their optimization. In response to these limitations, and using 3D printing, a new sitting-drop bridge has been designed and developed, where five crystallization drops can be placed simultaneously in each well of a 24-well crystallization plate. This significantly simplifies the process and increases the potential of sitting drops in crystal optimization, reducing costs and hence overcoming the limitations of current approaches.