COLL 136 |
| Daphne Weihs, Department of Chemical Engineering, Techinon - Israel Institute of Technology, 32000 Haifa, Israel, Dganit Danino, Department of Food Engineering and Biotechnology, Technion, Technion City, Haifa, 32000, Israel, Fred M. Konikoff, Dept. of Gastroenterology, Tel Aviv Sourasky Med, Ctr. and Minerva Ctr. for Cholesterol Gallstones and Lipid Metabolism, Tel Aviv University, 69978 Tel Aviv, Israel, and Yeshayahu Talmon, Department of Chemical Engineering, Technion - Israel Institute of Technology, 32000 Haifa, Israel. |
| We have used cryogenic temperature transmission electron microscopy (cryo-TEM) combined with cryogenic electron diffraction (cryo-ED) to study crystal formation and development in nucleating model and native biles. Well-characterized bile models, as well as native gallbladder biles from cholesterol gallstone patients were studied sequentially to elucidate cholesterol nucleation and crystallization. We imaged the forming microstructures by cryo-TEM, and characterized the crystals in the diffraction mode of the TEM. The growth and stability of classic cholesterol monohydrate crystals in model and native bile was determined. Electron diffraction provided also direct proof of the existence of a novel cholesterol monohydrate polymorph in bulk solution. We observed no evidence of pure anhydrous cholesterol crystallization in any of the biles studied. The experimental approach may be used to investigate not only the factors that influence biliary cholesterol nucleation and crystal formation, but many other processes of nucleation and growth of crystals in liquid systems. |
|
Bio-Colloids
2:00 PM-4:30 PM, Monday, March 29, 2004 Marriott -- Grand Ballroom K, Oral
Division of Colloid and Surface Chemistry |