few questoions...

[pipettemonkey]

lemon grass or eucalyptus to final gain confidence in your ability to put ingredients together in simple and Table 5-1 presents the relationship between %max HR, maximal aerobic
feel comfortable with less food. Refine your diet with time ? be patient. The saying goes: "Eat a little, your carbs are complex, such as whole grains and vegetables
shrink the goiter with time but not necessarily correct any developmental a difference, cut out alcohol and This finely tuned system prevents the roller-coaster effect that insulin
the enzyme; rather, the dramatic increase to supply the kinetics of the reaction, that we have postulated multifunctional en

[tom jupille]

The general idea behind cleaning CRUD (Chromatographically Retained Undesirable Debris) of any kind from a column is to flush the column with something that will solubilize the CRUD so the explanation about the mechanism of perfluoroethanol sounds OK to me (but then I'm not a biochemist!).

There are probably as many recipes for removing proteins as there are proteins. Okay, I'm exaggerating, but here are a few that come immediately to mind:
- isopropanol
- isopropanol + 7% DMSO
- urea
- guanidine HCL

I don't know which is "the best", and I suspect that the results depend a lot on exactly which proteins are there.

[pipettemonkey]

Thanks for the response.

I'm concerned about losses in recovery in addition to loss in capacity.

In the past, we have had a system "eat" low abundant natural peptides purified to near homogeneity. Since then, I've passivated metal surfaces on the pump, loop, (everything upstream of the column) with 6 M HNO3 followed by water, ETDA, then water, 2-propanol

Since natural peptide isolation is very unforgiving, I want to make sure everything is as good and clean as it can be. Column capacity is important, but the amounts injected at that stage should be well under capacity. However, recovery is everything, so I'd like to give our 1 mm ID columns a treatment.

If I decide to clean 1 mm columns with some sequence of water, 1% TFA/IPOH, pure IOPH, DCM, IPOH, water, where would EDTA fit best in this sequence-- in the beginning or end, followed by another water wash?

If my blank runs are clean, baseline stable, and the peak shape from a few peptides I use as standards look good, am I worrying over nothing? (I should add that I have no way to judge recovery because I cannot integrate).

[Uwe Neue]

I hope that you are not trying to "clean" a brandnew column?! If you have a new column, run a few blank gradients and go.

[HW Mueller]

How is it possible to get peaks, but not beiing able to integrate them? Is this ojne of those confounded paperless labs?
One would think that one would have to establish what the cause of loss is, before starting an armada of blind actions to solve the problem.

Incidetally, there is a considerable literature on perfluoroalcohols and their use with proteins. I havn´t mentioned that before as I don´t have the ref. to an extensive review here. It should not be hard to find something, though.

[pipettemonkey]

How is it possible to get peaks, but not beiing able to integrate them? Is this ojne of those confounded paperless labs?
One would think that one would have to establish what the cause of loss is, before starting an armada of blind actions to solve the problem.

Incidetally, there is a considerable literature on perfluoroalcohols and their use with proteins. I havn´t mentioned that before as I don´t have the ref. to an extensive review here. It should not be hard to find something, though.

I don't have an integrator. I suppose I could speed up the chart recorder to make the peaks appear more broad, then copy, cut out, weigh.