2d-gc

[jiangds06]

I did not see a lot of 2d-gc on the market? Is there any problem intrinsic to this kind of instrument? and why there is no 2dlc instrument on the market based on the same concept?

[II5tickmanII]

We had this pitched to us by a well known supplier some time ago as the new thing in GC.

At a glance yes 2D-GC is "new and shiny" but the additional information you can gain is for the most part not needed in industry. Or, can just as easily be gathered by other means, in the majority of cases means which have established proven methods and are somewhat common place for the applications desired.

I would imagine there is not a need for 2D-LC as you can just use a diode array detector which is essentially the same thing but better. I really enjoy using diode arrays but sadly havent been able to for some time

[Don_Hilton]

2D-GC covers a number of possible configurations. You can set a up heart-cutting technique as simply as by adding valving and a second column in a standard GC. You may need an independent heated zone - which can involve a column nounted outside the GC or in a second GC (with a bit of plumbing and some electrical connections). Heart-cutting thechniqes have been around for years.

Instruments are being used - some "home built."

An interesting 2D-GC area is comprehensive 2D-GC or GCxGC. There are several vendors of this type of equipment - and a patent, which keeps the number of vendors limited - for now. If you follow GCxGC in literature searches, you see this area to be growing significantly.

2D LC is a bit tricky as you need to keep solvent compostiion in mind while taking the eluent from one column onto another. But there are applications out there.

[aldehyde]

Agilent sells a few different microfluidic switching products that allow for heart cutting and 2D GC. http://www.chem.agilent.com/en-US/Suppo ... 01312.aspx

I think all major vendors have these options, they're relatively new (compared to GC ) but I know several people that use them with a lot of success. What are you trying to do?

As Stickman said the new and fancy techniques aren't cheap, and if you can get accomplish the same goals without the added complexity and expense you are often better off. That said, it IS cool as heck and can be used to do some very interesting stuff.

[jiangds06]

Thanks for all the comments.
anyone know any vendor produce 2dlc?

2D-GC covers a number of possible configurations. You can set a up heart-cutting technique as simply as by adding valving and a second column in a standard GC. You may need an independent heated zone - which can involve a column nounted outside the GC or in a second GC (with a bit of plumbing and some electrical connections). Heart-cutting thechniqes have been around for years.

Instruments are being used - some "home built."

An interesting 2D-GC area is comprehensive 2D-GC or GCxGC. There are several vendors of this type of equipment - and a patent, which keeps the number of vendors limited - for now. If you follow GCxGC in literature searches, you see this area to be growing significantly.

2D LC is a bit tricky as you need to keep solvent compostiion in mind while taking the eluent from one column onto another. But there are applications out there.

[chromatographer1]

All it requires is a switching valve (an extra sample valve would work) if you keep the mobile phase the same while changing columns, and perhaps a second detector.

This depends upon the application required and the selectivity of the columns needed.

Folks have done this since the 1980s, but as proprietary lab work. Not published or commercialized.

best wishes,

Rod

[Peter Apps]

Agilent sells a few different microfluidic switching products that allow for heart cutting and 2D GC. http://www.chem.agilent.com/en-US/Suppo ... 01312.aspx

I think all major vendors have these options, they're relatively new (compared to GC ) but I know several people that use them with a lot of success. What are you trying to do?

As Stickman said the new and fancy techniques aren't cheap, and if you can get accomplish the same goals without the added complexity and expense you are often better off. That said, it IS cool as heck and can be used to do some very interesting stuff.

Lest we forget; heart cutting GC-GC dates back to Deans' work in 1968, so it actually predates capillary columns. Chrompack had a commercial system in the late 80s, and Seimens' double oven system came out in the early 80s. They were all very fiddly to set up, and a pain to keep working. What made Dean's switching attractive enough to be commercialy viable was electronic flow control which made it robust to flow and pressure fluctuations during temperature programming, and vapour phase deactivation of metal surfaces which allowed them to be physically robust.

Peter

[Johnny Rod]

I think the lack of off-the-shelf 2D instruments is because each set-up is specific for a piece of work, and quite narrowly focused on both the analytes and the aims of the modifications (different separation, higher sensitivity etc.). Maybe there are one or two for common jobs e.g. a petrochem application or something EPA, in the same way that GCs are sold as "analysers" i.e. ready set up for a certain method. Other than that you really need to know what you want it to do.

[HW Mueller]

Sure enough it has been around for some time, examples from myself:
J Chromatogr, Biomedical Applications, 228, 75 (1982) [FA by GC]
Journal of Chromatography B: Biomedical Sciences and Applications, Volume 678, Issue 2, 12 April 1996, Pages 137-150 [cortisol in blood via HPLC]

[antonk]

This is example how we made GC x GC using Restek connectors and HP valve from ancient HP-5890
http://inp.bsu.by/labs/lar/GCxGC.pdf

This the software used to build the playground:
http://www.unichrom.com/gcxgc/gcxgce.shtml

P.S. Please read the PDF title "Using stock GC"

[Peter Apps]

And here's mine:

APPS, P.J. 2006. Low cost, robust, in-house hardware for heart cutting two-dimensional gas chromatography. Journal of Separation Science 29: 2338-2349.

http://onlinelibrary.wiley.com/doi/10.1 ... 834.d02t04

The joy of tinkering !

Peter

[jiangds06]

Really appreciate all of response. thanks.

And here's mine:

APPS, P.J. 2006. Low cost, robust, in-house hardware for heart cutting two-dimensional gas chromatography. Journal of Separation Science 29: 2338-2349.

http://onlinelibrary.wiley.com/doi/10.1 ... 834.d02t04

The joy of tinkering !

Peter