How about low pH elution or EDTA as alternative ? Jürgen ...................... Jürgen Bosch Johns Hopkins Bloomberg School of Public Health Department of Biochemistry & Molecular Biology Johns Hopkins Malaria Research Institute 615 North Wolfe Street, W8708 Baltimore, MD 21205 Phone: +1-410-614-4742 Lab: +1-410-614-4894 Fax: +1-410-955-3655 http://lupo.jhsph.edu
On Aug 21, 2013, at 14:40, "Prof. Dr. Arne Skerra" <ske...@tum.de<mailto:ske...@tum.de>> wrote: Hi Bernhard, We know this problem since the very early days of the His-tag and have been using high purity imidazole from Merck since then with success, which essentially shows no absorption at 280 nm. If you like I can enquire the current order number in my lab. Cheers, ASk Am 21.08.2013 um 16:33 schrieb Bernhard Rupp: Hi Fellows, could someone please point me towards the source of a known high purity imidazole with low absorbance at 280 nm? I am facing the problem of detecting a low absorption protein in high imidazole background after IMAC gradient elution. In the UV spectra of the 2 imidazoles I checked there is some contaminant that absorbs at 280… Thx, BR ---------------------------------------------------------------------------------------- Bernhard Rupp Marie Curie Incoming International Fellow Innsbruck Medical University Schöpfstrasse 41 A 6020 Innsbruck – Austria +43 (676) 571-0536 bernhard.r...@i-med.ac.at<mailto:bernhard.r...@i-med.ac.at> ---------------------------------------------------------------------------------------- Dept. of Forensic Crystallography k.-k. Hofkristallamt Vista, CA 92084 001 (925) 209-7429 b...@ruppweb.org<mailto:b...@ruppweb.org> b...@hofkristallamt.org<mailto:b...@hofkristallamt.org> http://www.ruppweb.org/ ----------------------------------------------------------------------- Prof. Dr. Arne Skerra Lehrstuhl f. Biologische Chemie | Technische Universitaet Muenchen Emil-Erlenmeyer-Forum 5 | 85350 Freising-Weihenstephan | Germany Phone: +49 (0)8161 71-4351 | Fax: -4352 http://www.wzw.tum.de/bc | eMail: ske...@tum.de<mailto:ske...@tum.de>
