Chromatography Forum

Hi everybody!,

we have to analise the residual solvents (dichloromethane and ethanol) by GCMS in a polymer soluble in H2O. The concentration would be 50-200 ppm. We don't have access to headspace autosampler but we could do manual headspace.
We think to use n-propanol as ISTD for correct the variability of the injection and to dissolve the polymer with water, heat at 80°C for 20 min and inject 0,5mL of headspace.

1) Is correct the choice of the ISTD?
2) Do you think is better to add a small quantity of DMF or DMSO (1%) to the water to better dissolve the component?

Thank you very much in advance

Have a good day!

I would use another internal standard. THF or n-propanol or methanol might be better.

I would not add DMF or DMSO. If you need to improve solubility try methyl cellusolve.

I assume you will be using a Carbowax capillary.