Multiple injections acquired in one chrmomatogram in Empower 2

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Kevin Kelly
Kevin Kelly's picture
Multiple injections acquired in one chrmomatogram in Empower 2

Hello Everyone,

Can Empower 2 be used to acquire a single chromatogram from a Agilent 1200 that captures multiple 1-minute injections?  I want to capture multiple (10-15), short (1 minute runtimes) injections as fast as possible on the same chromatogram.  Is this doable?  Thanks in advance for your help.

Kevin Kelly, PhD
R&D Analytical Manager
Mikart, Inc.
1750 Chattahoochee Avenue
Atlanta GA 30318
Phone: 404-351-4510 Ext: 316
Fax: 404-355-7654

Dr. Analytical
Dr. Analytical's picture
Kevin:

Kevin:
Thanks for posting on scientistsolutions.com.

I am not sure if this will be possible in Empower.  In the ChemStation, you would have to set up an injector program to do the multiple injections, but I don't know if this option is implemented in Empower (only an occasional Empower user, sorry). 

Why do you want to do this all in one injection, rather than just setting up multiple 1 minute runs and overlaying the chromatograms? 
 

Kevin Kelly
Kevin Kelly's picture
Thank you for replying.

Thank you for replying.
Yes in Chemstation you have the overlap injection option, but in Empower you don't (apparently - Waters couldn't tell me for sure!!).
I am trying to minimize the time between sample injections to the shortest period.  I am not using the HPLC as an HPLC, rather as an autosampler for measuring a colorimetric test (analysis of phosphate by the malachite green procedure) that has a 20-minute time limit (last reagent added through reading at 630nm). I thought the injector recycle time would be the shortest interval so I didn't think empower could cycle as fast - so I wanted empower to just read while the 1200 injected away!!  However, I've come to determine that the recycle time of a Agilent 1200 is a little more than 1 minute so the autosampler is actually the limiting factor.

In the olden days, I would have used a recorder and did just what I was proposing, but today everything is so interconnected electronically!

Dr. Analytical
Dr. Analytical's picture
Kevin:

Kevin:
Which autosampler do you have?  The well plate version is considerably faster than the standard version.  And if you have the standard version, place your samples in the closest vial positions (80's and 90's).  That will save you a few seconds each time.  If you have access to the draw rate settings in the autosampler, set those to faster values. 

Interesting application.  Is it working well for you otherwise?

Kevin Kelly
Kevin Kelly's picture
We have the standard vial

We have the standard vial autosampler on a Rapid Resolution 1200. Yes we thought about the microplate reader (can't justify the cost and "losing" an HPLC). In fact, the method we are reproducing was based on the microplate techniolgy (if you're interested: J.Environ.Qual. 30:2206-2209 (2001)).  I'll look at the draw rates (yes, available in Enpowe) and will evaluate vial placement within the autosampler.  Thanks for the ideas.

I was just thinking outside the box!

Dr. Analytical
Dr. Analytical's picture
The well plate autosampler

The well plate autosampler can be configured for standard vials if necessary, but it is usually in a different format (two trays of 56 vials each).  I don't know if the standard 100 vial tray is available.

"I was just thinking outside the box!"

Love it! Keep doing that!