Hello,

I am currently looking for an HPLC autosampler to inject volumes ranging between 10ul and 1ml for high sensitivity fluorescence detection. A system compatible with vials and multiwellplate formats would be appreciated.

For one application, the injection of a total of 1 ml of sample, we consider two technical solutions to fill the injection loop:
- multistep sample uptake (10x100ul)(e.g. : Agilent G1367A)
- single step sample uptake (mounting syringe of appropriate volume) (e.g. : LC-Packings, Famos).

Questions :
1.Are there arguments for one or the other technical solution.
2.Are there any expected or known differences in performance concerning sample carry-over among these or other currently available autosamplers? (Needle wash efficiency?)
3.Are there efficient autoinjection protocols (internal & external needle wash) which reduce sample carryover when fluorescence detection at maximal sensitivity has to be used?

If you have any advice or experiences which allow to identify the most appropriate technical choice and to reduce the probability of getting ghost peaks due to carry over during injection, I would appreciate getting your advice.

Thank you in advance for considering these questions.

Fred


Fred Fack, Ph.D.
LNS-Div. Immunology
20a, rue Auguste Lumière
L-1011 Luxembourg
Tel.:+352-490635
Fax.:+352-490686
email.:fred.fack@lns.etat.lu

In adjunct to Agilent and LC Packings consider also CTC ANALYTICS at www.ctc.ch
I have never used an LC autosampler from CTC but specification and versatility, as proposed in various journals, are very promising.
Good luck.