Materials Research Science and Engineering Center

Fox Baudelaire

“Steps in the development of a microfluidic device for protein crystallization”

Fox Baudelaire, S. Ali Aghvami, Seth Fraden
Brandeis / Biological Physics and Chemical Biology
Hosted by Fraden's Lab

Abstract

X-ray crystallography remains the most utilized method for the determination of a protein’s three-dimensional molecular structure. In order to generate a diffraction pattern that can be accurately interpreted, it is critical to obtain well-ordered crystals of the protein. Conventional methods for protein crystallization at the macroscale are highly sensitive to various factors (e.g. temperature, precipitant composition), affording the user limited control and assurance in crystal production. In this work, we report progress in a project to develop a microfluidic device capable of screening from multiple sets of crystallization conditions of a protein by counter-diffusion.

We employ techniques in photolithography and soft lithography to fashion device prototypes out of PDMS (polydimethylsiloxane). Prior work had developed a method for the passive control of aqueous drops in a microfluidic device. Harnessing the surface tension of aqueous drops according to this method, we expect to be able to sequentially load and sequester different mixtures of buffer and precipitants without mixing. We have improved the design to remove excess aqueous phase and accommodate four, user-controlled, manual valves that allow the user to control the direction of fluid flow in a device prototype when enclosed in an aluminum jig of our making. Finally, we also offer considerations for further testing and development of the device.

Support

SMURF (Summer MRSEC Undergrad Research Fellowship)