which lc/ms/ms?

[epld]

Hello, I need help.
I work in a environmental lab and we're going to to buy our first lc/ms/ms system.
We hesitate beetween 3 systems: Micromass (Waters), API3000 (Applied biosystems) and Finnigan TSQ (Thermo Finnigan)
I would like opinions of users of these systems in order to choose the best one, especially for pesticides search in water, food...
Thanks.

[MG]

Do you see yourself focusing more on qualitative analysis, or quantitative analysis?

[epld]

I focus on both but especially on quantitative analysis.
But your opinion interests me: which one is better for quantitative? For qualitative?

[MG]

I ask because in general, triple-quads are better for quantitation, and ion traps are better for qualitative analysis.

The API-3000 is an excellent instrument for quantitation, but I haven't used the Finnigan TSQ or any Micromass instrument, so I don't have a basis for comparison.

[mass]

i hav experience with micromass ultima, sciex and agilent MSD trap , comparing these three instruments sciex is the best one, sensitvity wise for quantification. For qualitative work Agilent MSD Trap is best.

My suggestion is API 3000 is the best one.

[CE Instruments]

For quantitative analysis Triple Quads are generally best but Traps can run them close. You make no mention of budget ? Can you afford a good Triple ? If performance is the requirement the Thermo Quantum is the only system with high resolution unless you consider a sector. Note TOF systems are high resolution but are not as good for quantitative work. If you have cash to spend make sure you ask each manufacturer to run a sample and if possible visit them all to find out just how easy they are to run.

[bert]

This can develop to the largest post on the board! Why dont you try it yourself: prepare a number of test samples, take real-life samples and let the company's run these samples on their instruments. Maybe you will be suprised.

regards Bert

[John G]

Definitely follow Bert suggestion and submit samples to the manufacturers for analysis, they have demo labs for just this purpose and the love to show their capabilities. I have come to one conclusion about this topic, it's all compound dependant. For every example of one instrument showing superior sensitivity over it's competitors someone else can show you a different compound where the results are the opposite. The truth is they are all very capable instruments that is why they are the big three. The second biggest factor in sensitivity is the operator's ability. The effect of an inexperienced or poorly trainned operator eliminates any differences in the instruments. Experience and training count when it comes to absolute detection levels, whoever you purchase from make sure a training course is included in the deal.

95% of the time all three instruments will gives you more sensitivity then you actually need. Your decision should not be based on absolute detection limit but rather on the one thing that will affect your work, getting your work done on time. If the instrument isn't up and running then you have a problem. Service and support is what makes one instrument the right choice over the others. Find out how many services reps they have in your area, what there average time to arrive is, find out how to contact their applications support team and make friends there, they can save you a lot of wasted time and effort.

Go with the manufacturer that you feel offers the best "package" and don't worry about what other people say, they are all great instruments.

[epld]

Thanks for all yours councils.

[matthias]

Take care, that you take YOUR ref substances, Buffers and columns to really have comparable results. Else you have data based on different situations which you cannot compare, because each application chemist has his ideas.