title: Double-focusing mixing jet for XFEL study of chemical kinetics.
abstract: Several liquid sample injection methods have been developed to satisfy the requirements for serial femtosecond X-ray nanocrystallography, which enables radiation-damage-free determination of molecular structure at room temperature. Time-resolved nanocrystallography would combine structure analysis with chemical kinetics by determining the structures of the transient states and chemical kinetic mechanisms simultaneously. A windowless liquid mixing jet device has been designed for this purpose. It achieves fast uniform mixing of substrates and enzymes in the jet within 250 µs, with an adjustable delay between mixing and probing by the X-ray free-electron laser beam of up to 1 s for each frame of a `movie'. The principle of the liquid mixing jet device is illustrated using numerical simulation, and experimental results are presented using a fluorescent dye.
authors.affiliation: Department of Physics, Arizona State University, PO Box 871504, Tempe, AZ 85287-1504, USA.
authors.forename: Dingjie
authors.initials: D
authors.lastname: Wang
authors.affiliation: Department of Physics, Arizona State University, PO Box 871504, Tempe, AZ 85287-1504, USA.
authors.forename: Uwe
authors.initials: U
authors.lastname: Weierstall
authors.affiliation: School of Applied and Engineering Physics, Cornell University, 254 Clark Hall, Ithaca, NY 14853, USA.
authors.forename: Lois
authors.initials: L
authors.lastname: Pollack
authors.affiliation: Department of Physics, Arizona State University, PO Box 871504, Tempe, AZ 85287-1504, USA.
authors.forename: John
authors.initials: J
authors.lastname: Spence
mesh_terms: D002621:Chemistry; D018360:Crystallography, X-Ray / Q000379:methods*; D006801:Humans; D007700:Kinetics; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D008956:Models, Chemical
keywords: chemical kinetics; mixing jet; sample injection; time-resolved diffraction