Never had problems with evaporation (and this is in the relatively dry
climate of Denver, CO, especially in the winter when the relative
humidity is in the low 20%).
Using the Thermo Scientific Nanodrop 2000c.
We use it also as a prerequisite for ITC, which can be very sensitive
to proper concentrations.
F
On Jun 16, 2011, at 1:15 PM, Arnon Lavie wrote:
Dear fellow crystallographers - a question about spectrophotometers
for protein concentration determination.
We are so last millennium - using Bradford reagent/ 1 ml cuvette for
protein conc. determination.
We have been considering buying a Nanodrop machine (small volume, no
dilution needed, fast, easy).
However, while testing our samples using a colleague's machine, we
have gotten readings up to 100% different to our Bradford assay (all
fully purified proteins). For example, Bradford says 6 mg/ml,
Nanodrop 3 mg/ml. So while it is fun/easy to use the Nanodrop, I am
not sure how reliable are the measurements (your thoughts?).
So QUESTION 1: What are people's experience regarding the
correlation between Nanodrop and Bradford?
While researching the Nanodrop machine, I heard about the Implen
NanoPhotmeter Pearl.
So Question 2: Is the Pearl better/worse/same as the Nanodrop for
our purpose?
Thank you for helping us to advance to the next millennium, even if
it is nearly a dozen years late.
Arnon
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Arnon Lavie, Professor
Dept. of Biochemistry and Molecular Genetics
University of Illinois at Chicago
900 S. Ashland Ave.
Molecular Biology Research Building, Room 1108 (M/C 669)
Chicago, IL 60607
U.S.A.
Tel: (312) 355-5029
Fax: (312) 355-4535
E-mail: la...@uic.edu
http://www.uic.edu/labs/lavie/
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