Nanoliter-scale protein crystallization and screening with a microfluidic droplet robot.
Large-scale screening of hundreds or even thousands of crystallization conditions while with low sample consumption is in urgent need, in current structural biology research. Here we describe a fully-automated droplet robot for nanoliter-scale crystallization screening that combines the advantages of both automated robotics technique for protein crystallization screening and the droplet-based microfluidic technique. A semi-contact dispensing method was developed to achieve flexible, programmable and reliable liquid-handling operations for nanoliter-scale protein crystallization experiments. We applied the droplet robot in large-scale screening of crystallization conditions of five soluble proteins and one membrane protein with 35-96 different crystallization conditions, study of volume effects on protein crystallization, and determination of phase diagrams of two proteins. The volume for each droplet reactor is only ca. 4-8 nL. The protein consumption significantly reduces 50-500 fold compared with current crystallization stations.
Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China.
Ying
Y
Zhu
Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China.
Li-Na
LN
Zhu
Life Sciences Institute, Zhejiang University, Hangzhou, 310058, China.
Rui
R
Guo
Life Sciences Institute, Zhejiang University, Hangzhou, 310058, China.
Heng-Jun
HJ
Cui
Life Sciences Institute, Zhejiang University, Hangzhou, 310058, China.
Sheng
S
Ye
Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China.
Qun
Q
Fang
D003460:Crystallization / Q000379:methods*; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000379:methods*; D008958:Models, Molecular; D011487:Protein Conformation; D012371:Robotics; D014961:X-Ray Diffraction
D008565:Membrane Proteins