TMSH methylation of fatty acids

[ami1and]

hallo,
I have a problem with TMSH. I use it for the methylation of fatty acids witch are solved in n Hexane. The problem is, that the syringe for injection alwayes get blocked after injection of some sampels.
Thank you for help...

[Don_Hilton]

How are you washing the syringe after injectinon? The autosamplers I am familiar with allow you to use two solvents so you can use a second solvent to remove compounds that do not wash out of the syringe well with the first.

There may be particulates or some other problem with your samples, but with the limited description, I can offer only a generalized comment.

[RAD]

We have had the same problem with various silating agents and fatty acid derviatization. The syringes get very sticky after several injections. We have found that rinsing the syring with a mixture of hexane/methylene chloride/acetone (equal volumes of each), helps to extend the life of the syringe.