Chromatography Forum

Hello,

I wondered if anyone can provide an answer the issue I am currently having, I am running a Chiral method, which requires derivatisation.
My sample is heat sensitive so the autosampler is 10C.
My mobile phase is phosphate buffer pH3.0 / methanol and the sample diluent aqueous pH3.0.

Since I am doing method development I am worried about the instrument, and have yet to complete SST to assure the system is injecting reproducibly.

What areas would please suggest I look at, needle and needle wash?
Could it be a leak from the needle wash as opposed to sample leak from the needle?

FYI Instruments is a Waters 2695.
Thanks for any tips!

Two things occur to me: 1. Condensation. Being that your sample compartment is 10 deg C, some condensation is possible on the vials depending upon the relative humidity in your lab. I don't see that as a huge issue, honestly 2. A leaking seal pack. How long has it been since the instrument received a PM?

Hi, I would consider condensation, but this does not look like condensation. We do get build up as expected as we switch form 10 to 25C, but this kit is kept at the lower temp.

A leaky seal pack......that sounds bad! This kit is a RnD kit and we try and maintain as best we can, we have a call outs when we need them though, so perhaps this is one of those occasions....

Thanks!