Chromatography Forum

Hi,

I am getting set to try to study the optical properties of some polymeric materials as a function of molecular weight. I have two detectors, a dual wavelength UV/vis and a fluorescence detector. Ideally, I would like to have a set of MW standards that will be seen in both detectors. Anyone know of any polymeric materials in the 10^2-10^5 Da range that could be used this way? I am just getting back into SEC work; in my last go-around I was working with PEG standards. I am interested in determining the exact 'latency' between the detectors. The fluorescence detector follows after the absorbance detector. To determine the latency I could just choose a conservative tracer that doesn't bind on the column. However I thought I'd throw this question out there. In an ideal world I would be certain that my detectors give the same relationship b/w MW and RT on the same standards. I have no expectation that they would not, but I would like to prove it just once.

Thanks,

David

I actually have experience of GPC using UV. I used Polystyrene. I hope this application will help you.
http://www.shodex.com/english/dc060503.html

You may find more information following Web.
http://www.shodex.com/english/dc0605.html
https://www.waters.com/webassets/cms/li ... /lcGPC.pdf

Best Regards,

I can't think of a polymer that fluoresces. You could use some standard polymer and label it. Another and maybe better approach could be to throw something that has fluorescence into the mobile phase as an additive and then simply observe the suppression of the fluorescence from the UV-absorbing polymer, for example polystyrene in a THF mobile phase. You will get a positive response in the UV-detector and a negative response in the fluorescence detector.

If it doesn´t have to be polymers, just macro molecules, then some protein standard(s) may do. Many of these fluoresce.
There is no doubt that you get a time set-off between detectors in series. If you correct for this the RT will be identical, so what is the reasoning behind proving anything here?