An article describing the design and testing of a new PDMS-based micro-sprayer, in collaboration with the Columbia Engineering Department, has just been accepted by the journal STRUCTURE:
A Fast and Effective Microfluidic Spraying-plunging Method for High-Resolution Single-Particle Cryo-EM
Xiangsong Feng, Ziao Fu, Sandip Kaledhonkar, Yuan Jia, Binita Shah, Amy Jin, Zheng Liu, Ming Sun, Bo Chen, Robert A. Grassucci, Yukun Ren, Hongyuan Jiang, Joachim Frank, and Qiao Lin.
We describe a spraying-plunging method for preparing cryo-EM grids with vitreous ice of controllable, highly consistent thickness using a microfluidic device. The new polydimethylsiloxane (PDMS)-based sprayer was tested with apoferritin. We demonstrate that the structure can be solved to high resolution with this method of sample preparation. Besides replacing the conventional pipetting-blotting-plunging method, one of many potential applications of the new sprayer is in time-resolved cryo-EM, as part of a PDMS-based microfluidic reaction channel to study short-lived intermediates on the time-scale of 10 to 1000 ms.