Triazoles from spray dried algae by QUECHERS

[James_Ball]

I am trying to extract 5-Methyl-1H-Benzotriazole from samples of spray dried algae and I am wondering if I should hydrate before extraction or not?

I am working from a method I found looking for triazoles in fruits and vegetables extracting with Ethyl Acetate with Sodium Sulfate and Sodium Hydrogen Carbonate. Of course the fruits and vegetables are higher moisture matrix than the spray dried algae is, so not sure if I need to add water or how much. I have not had much experience with Quechers in the past so wondering if anyone else has any ideas.

I am using Magnesium Sulfate/PSA cleanup after extraction then direct injection of the Ethyl Acetate into GCMS SIM or MRM.

[Don Shelly]

Hi James,

It looks like you are using the SWEET Method (Swedish Ethyl Acetate Method) rather than QuEChERS. Traditional Q uses acetonitrile/water with magnesium sulfate and a buffer. If using a QuEChERS method, I recommend the AOAC 2007.01 version.

Hydrating your matrix will improve extraction efficiency.

Don

[James_Ball]

Hi James,

It looks like you are using the SWEET Method (Swedish Ethyl Acetate Method) rather than QuEChERS. Traditional Q uses acetonitrile/water with magnesium sulfate and a buffer. If using a QuEChERS method, I recommend the AOAC 2007.01 version.

Hydrating your matrix will improve extraction efficiency.

Don

Thanks Don.

I actually did both methods dry. Ethylacetate for the GCMS and Acetonitrile for the LCMSMS. I ran them dry because I believe these were spray dried using dextrose or other sugar and I wasn't sure if adding water would just turn them to goo. Client was in a hurry for some results, but I am going to go back and make a hydrated run also.

I ended up using the GCMS because it was faster to develop the SIM method on that. Had a little tailing on the lowest standards but not too bad. I got about 80% recovery from spiked matrix and was able to tell that the samples had been contaminated versus a known clean sample, though the peak was quite small. They are sending further samples so I may go ahead and develop the LCMSMS method for a confirmation.