Evaporative LIght Scattering

[bdhedhy19]

Hi all,
I have to develop the method using Evaporation Light Scattering (PL-ELS 2100 detector). I want to use DMF instead of THF, wonder if it is possible? if i increase the evaporation temperature or if you have any suggestion, please let me know.

thanks

[Consumer Products Guy]

Hi all,
I have to develop the method using Evaporation Light Scattering (PL-ELS 2100 detector). I want to use DMF instead of THF, wonder if it is possible?

Yes. You likely will need to raise the nebulizer temperature.

[Vlad Orlovsky]

Why do you want to use DMF? Any particular reason, like selectivity, solubility or else? I can't imagine a reason why you want to do this.

[fchq2001]

Hi all,
I have to develop the method using Evaporation Light Scattering (PL-ELS 2100 detector). I want to use DMF instead of THF, wonder if it is possible? if i increase the evaporation temperature or if you have any suggestion, please let me know.

thanks

As I know the evaporation temperature is depends on the sample

[bdhedhy19]

thanks for the tips with ELSD, really appreciate it

I used DMF for PMMA and polyurethane samples using Wyatt Instrument (Refractive Index) for another company, now i am working for different company and they have ELSD GPC Instrument.

I dissolved the samples and PMMA in DMF and it shows peaks, Now i am trying to adjust the Nebulizer temperature and evaporative temperature to get resolved and smooth peak.

Agilent recommended to use Ammonium acetate or Ammonium formate (0.1%) in DMFmobile phase. I will try to increase the Nebulizer temperature and will see.

Yes, Vlad Orlovsky I want to use DMF, because of the good solubility of most of the samples. Which solvent would you recommend for ELSD GPC.
Please let me know
Best Regards

[Vlad Orlovsky]

from my experience a lot of compounds dissolve in EtOH/THF mixture. My guess is that with DMF you will need to set up temperature of ELSD around 100*C. Make sure that your compounds are not evaporating at this temperature becuase you will see poor linearity at lower concentrations.

[bdhedhy19]

Thanks Vlad for your suggestion:)
what ratio would you recommend for this THF:EtOH mixture (90% THF:10% EtOH) or what? Please let me know
when you have time.
I really appreciate it.
thanks so much
Best Regards