Related Experiment Video
Updated: Apr 26, 2026

Crystallization of Proteins on Chip by Microdialysis for In Situ X-ray Diffraction Studies
Published on: April 11, 2021
Cross polarization compatible dialysis chip
Micha Kornreich1, Michael Heymann, Seth Fraden
1The Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, 69978 Tel Aviv, Israel. roy@post.tau.ac.il.
Abstract:
We visualize birefringence in microliter sample volumes using a microfluidic dialysis chip optimized for cross polarization microscopy. The chip is composed of two overlapping polydimethylsiloxane (PDMS) channels separated by a commercial cellulose ester membrane. Buffer exchange in the sample chamber is achieved within minutes by dialyzing under continuous reservoir flow. Using fd virus as a birefringent model system, we monitor the fd virus isotropic to liquid crystal phase transition as a function of ionic strength. We show that the reorientation of the fd virus spans a few tens of seconds, indicative of fast ion exchange across the membrane. Complete phase separation reorganization takes minutes to hours as it involves diffusive virus mass transport within the storage chamber.
Related Concept Videos
Dialysis
Dielectric Polarization in a Capacitor
Ion Exchange
Potentiometry: Membrane Electrodes
Hemodialysis II: Procedure and Complications

