[RASMB] Plateaus in Absorbance?

[Peter Edward Prevelige Jr]

Hi All -

We are observing what appear to be plateaus in the absorbance profile in both equilibrium and velocity runs. The plateaus are seen with different samples and different rotor speeds. Our current hypothesis is that the slit in front of the detector is sticking and releasing.  It appears that these are lost steps as after the slit releases the exponential is shifted along the radial distance axis. Some representative data is attached showing different speeds and cells. The superimposed scans (cell 1 35K, & cell 1 44K) are scans recorded about 10 hours apart in time.

Is it reasonable to think that the slit is sticking? How can we diagnose and fix this problem?

Peter

Peter E. Prevelige Jr.
Professor
Dept. of Microbiology, BBRB 416/6
Univ. of Alabama @ Birmingham
845 19th St. South
Birmingham AL. 35294-2170
Phone 205 975-5327
FAX 205 975-5479
prevelig at uab.edu<mailto:prevelig at uab.edu>
http://www.microbio.uab.edu/faculty/prevelige/prevelige-p.htm

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