BruNo the Robot-A High-throughput Sample Handling System for Frozen Protein Crystals

Bob He, Brian Michell, Matt Benning, Cary Bauer, Dan Frankel, Roger Durst
Bruker AXS, Madison, Wisconsin, USA

It is a common practice that protein crystals are first screened by a laboratory X-ray diffraction system, and then selected crystals retrieved and transferred to synchrotron facilities for further study. There has been a great interest in the development of techniques to automatically screen large numbers of samples without human operator intervention. The BruNo robotics sample handling system is developed for this process. A 6-axis robot system is capable of handling protein crystals mounted on loop on a metal pin assembly. A proprietary Kryo-vial with liquid nitrogen absorption form is used to keep the crystal frozen during the loading and unloading, An X-Y-Z automated goniometer head and video image analysis software aligns each crystal into the instrument center. All crystals are stored in a dewar with revolving cover and flip lid to ensure minimum liquid nitrogen assumption. The liquid nitrogen level in the dewar is monitored and maintained by automatic refilling system. The screening software can trace and screen crystals with used selected scheme.