We are considering purchasing a CTC Analytics CombiPAL autosampler (through LEAP Technologies)for a new Agilent 6890 GC for both liquid and headspace sampling. I'd appreciate any experiences and recommendations. One thing we would worry about with any autosampler is bent syringes. How is the CombiPAL in that regard?

Mark

I've been using a CombiPAL on a Saturn 2000 for over a year now, with excellent results. The system is very reliable, and the only syringes I've bent have been SPME fibers. We do headspace extractions with the sample vial oscillating and the fixed SPME "needle" in the headspace. Needless to say, the needle tends to get a little bent. We found some crimp caps with a slightly wider needle hole, and that seemed to solve the problem. Haven't bent a needle yet doing liquid injections. Hope this helps.

John

I used a CombiPAL on a Shimadzu 17A for some high volume testing running 24/7 with a 4.5 min GC run time. No problems at all with the LEAP, although larger solvent vials would have been nice for my application.

Question:
when using the CPC system for headspace analysis, arent't the samples thermostated for different time ?
I have only seen a demonstration of the system but it seemed strange to me:
Let's say your sample has to be kept at elevated temperature of 70 °C for half an hour to obtain good results. So the 2nd sample was already thermostated for 1h, the third for 1,5 h etc.
Does it work that way ? How about degradation products ?

In the CombiPAL the samples are all heated for the same time if the parameters are entered correctly. You enter an equilibration time for the samples and a cycle time for the GC, and the firmware calculates when to place samples in the oven so they will be heated for the correct time period. If you enter the wrong GC cycle time, for instance neglecting the cooldown time and only entering the run time, then the samples may not be heated for the same time period.