Chromatography Forum

Dear members of the forum,

first of all I'm not sure whether this is the right category of the forum. But I think topic "Sample Prep" comes most close to my problem.

We are using the AI 1310 autosampler (ThermoScientific) with the rack for eight samples. Vials are 2 ml ones with crimp top. We are closing the vials with a manual crimper.
The problem is that sometimes the autosampler is dislodging the vial from the autosampler and throws it out. This is quite inconvenient as this happens usually while the syringe is washed with the sample and when the autosampler draws the actual sample there is no vial present anymore.

Has anyone experienced this as well?
Thank you very much for any tips or hints!

Regards,
Janosch

have you tried pre slitted septa on your vials?
if there is to much tention on the septum it might 'stick' to the needle and lift the vial out of the tray.

Hello BMU_VMW,

thank you for your reply! And sorry for taking so long to come back to that post. We had a holiday yesterday.
Actually, we are using the normal septas on the vials. So we might try these pre slitted once. But as we don't have any here, we need to order some.

other possibility is to check your injection needle.
the tip might be bend just a little to create a hook, or it can get a little rough when it is in use for quite a while.

BMU

Thank you for your other advice, BMU_VMW.
We are using the the syringe/needle since 10 months and approximately 300 - 400 injections. Just checked the tip of the needle, but it looks quite smooth.

just now saw this... you might want to try a different cap. I was using 11 mm crimp caps, and my injector was tossing vials all over the place. I switched to 9mm screw caps - problem solved!

Thanks again for all the advices. I think we solved it, as it didn't happen during the last runs. The problem might have been over-crimping. We adjusted the crimper and now it works fine, fingers crossed.