In my experience, some stained remain in the cartridge bed after cleaning/washing and regenerate the cartridge as well. You should use blank through the cartridge to confirm the carryover before re-using it. Although, you did not mention your analyte type but for your convenience I have stated some cartridge washing as well as storage procedures below:

1. Flushing with net organic solvent is usually sufficient to remove the contaminent, during flushing keep the elution flow rate initially low and after 40% solvent consuming make the flow rate faster.

2. If the flushing procedure does not solve the problem, purge the cartridge using the following procedur according to the type of analtye. Flush cartridges with 20 cartridge volumes of HPLC grade solvents:

a) Ploar Samples: Water > MeOH > THF (tetrahydrofuran) > MeOH > Water > Mobile Phase

b) Non-polar Samples: 70 IPA (Isopropylalcohol): 30 Water > THF > Dichlorometahne > Hexane > 70 : 30 Water > Mobilephase

c) Proteinaceous Samples:

Option 1: Repeated aliquots of DMSO (dimethylsulfoxide)

Option 2: gradient of 10% to 90 % of B

where, A= 0.1% TFA (trifluroacetic acid) in water and B = 0.1% TFA in ACN (acetonitrile)

Increase mobile phase temp. 35-40 oC increasecleaning efficiency.

3) Always store the cartridge immediately after use by soaking in 100% of ACN for the best cartridge life time.

Thanks with Regards.

Nawaz

Hi Leandro A Sánchez.

I would try to use the solvents that you stated but also with low and high pH for the elution of more acidic or basic compounds.

Have you used dicloromethane?

I hope I've helped.

In my experience, some stained remain in the cartridge bed after cleaning/washing and regenerate the cartridge as well. You should use blank through the cartridge to confirm the carryover before re-using it. Although, you did not mention your analyte type but for your convenience I have stated some cartridge washing as well as storage procedures below:

1. Flushing with net organic solvent is usually sufficient to remove the contaminent, during flushing keep the elution flow rate initially low and after 40% solvent consuming make the flow rate faster.

2. If the flushing procedure does not solve the problem, purge the cartridge using the following procedur according to the type of analtye. Flush cartridges with 20 cartridge volumes of HPLC grade solvents:

a) Ploar Samples: Water > MeOH > THF (tetrahydrofuran) > MeOH > Water > Mobile Phase

b) Non-polar Samples: 70 IPA (Isopropylalcohol): 30 Water > THF > Dichlorometahne > Hexane > 70 : 30 Water > Mobilephase

c) Proteinaceous Samples:

Option 1: Repeated aliquots of DMSO (dimethylsulfoxide)

Option 2: gradient of 10% to 90 % of B

where, A= 0.1% TFA (trifluroacetic acid) in water and B = 0.1% TFA in ACN (acetonitrile)

Increase mobile phase temp. 35-40 oC increasecleaning efficiency.

3) Always store the cartridge immediately after use by soaking in 100% of ACN for the best cartridge life time.

Thanks with Regards.

Nawaz

Thanks Saddam, I will try it. Actually, I want to recycle the sorbent, taking it out from the cartridge and assembling a bigger glass column. I will keep in mind your comments ! thanks again !

Hi Samir, Thanks for your comment. Yes, I will use basic and acid Ph, maybe TFA 0,1% would help. I didn't try with dicloromethane.

Thanks a lot

This might be a problem that is just intrinsic to silica. The silisc absorbs the color compounds very well and the binding could be so strong that you can't elite them.  If that is the case then it will still work if those compounds are stuck then they won't contaminate your other samples. It would be a good idea to run a blank using the solvents you are going to use in your method to ensue there is no contamination.

Thanks David, you are right. I have realized before that some pigments are strongly absorbed by the silica. It seems they will be there forever, so I just using a blank before charging the sample as you recommended. Of course, it would be better to have a nice, clean, white, and shiny silica. But, well.. is still working.

Thanks again !.

Please be aware if you reuse any SPE cartridge you'll never know what is it's actual capacity. Generally producer guarantees brand new cartridge capacity about 10% of it mass (30 mg SPE column will retain about 3 mg of different compound of similar class).Things that bind there permanently lowering that capacity in difficult to estimate level. If you're forced to reuse of disposable SPE, maybe you should consider turn to classical liquid-liquid extraction (eg. in microscale in eppendorf tubes and freezing out polar phase). Sometimes it's much cheaper then SPE and even more reliable.

Thanks Michal ! I will consider your idea.

For us, using a SPE for each sample is too expensive, so we had a protocol for cleaning Oasis HLB and Strata phenomenex cartbridge

1) 10 mL acetic ac 1%

2) 10 mL H20

3) 10 mL H20/MeOH (50/50)v/v

4) 10 mL MeOH

5) 10 mL Chlorophorm

6) 10 mL MeOH

7) 10 mL H20/MeOH (50/50)v/v

8) 10 mL H20

9) 10 mL acetic ac 1%

10) Let it dry

Gracias Juan Carrizo ! muy buen aporte !. Lo voy a tener en cuenta.Saludos !