Hello Fiaz, 

We use the C18 cartridges for the concentration or separation of anionic surfactants. The cartridge can be reused a few times, but should take care with regard to saturation or washing process (clean-up).

The washing procedure for C18 cartridges of 6 ml for anionic surfactants, is done by means ultra purified water (5 ml twice) and a strong organic solvent in the case methanol (5 ml twice).

For the lignin there must be a more specific procedure.

I hope this helps.

Best regards

Dear Fabricio, Thank you for your kind response !!