Remie, Actually, concentrating of a protein solution is not the best approach to removing low MW impurities, gel filtration chromatography is more reliable and ... faster.
Regards, Alex On Aug 19, 2014, at 7:03 AM, Remie Fawaz-Touma wrote: Hi Reza, I had to do this before. This protocol works for any PEG and any chemical to be removed from a solution: buffer exchange into the new buffer you want your protein to be in. There are ways to do that by 15 mL Amicon concentrators from millipore for large volumes, or if your protein is already concentrated, there are some small 0.5 mL concentrators from millipore as well. The key is to keep your spinning at low speeds (concentrators manuals will tell you) so you don’t precipitate or loose your protein. Check your protein concentration every 2 hours just to make sure you are not loosing it on concentrator surfaces and so on. Good Luck, Remie On Aug 19, 2014, at 9:55 AM, Reza Khayat <rkha...@ccny.cuny.edu<mailto:rkha...@ccny.cuny.edu>> wrote: Hi, Does anyone have a protocol for getting rid of PEG3350 from a protein sample? Best wishes, Reza Reza Khayat, PhD Assistant Professor The City College of New York Department of Chemistry, MR-1135 160 Convent Avenue New York, NY 10031 Tel. (212) 650-6070 www.khayatlab.org<http://www.khayatlab.org/>
