LC/MS/MS Recommendations

[chemboy831]

I'm beginning my research into purchasing a LC/MS/MS for my forensic tox laboratory. My top three choices in no particular order are: Agilent 6400 series QQQ, Agilent 6500 series Q-TOF, or the Applied Biosystems 4000 Q-Trap. Any recommendations? Advantages/disadvantages?
Thanks, Chemboy831

[mfiligenzi]

The best recommendation is, of course, to extract a set of samples from a matrix you will be working with that are fortified with analytes representative of those you'll need. Split the extracts and send them to the manufacturers. You may be surprised at the differences in performance.

I can't weigh in on the Agilent systems as I have no experience with them. The triple quad is relatively new, though, and I would strongly recommend speaking with a current user. It can take a fair amount of time for any manufacturer to work out the bugs on a new system and you don't want to be part of that process. That said, the Agilent system may work very well. (I also have no experience with the Q-TOF. Perhaps someone else can weigh in on it.)

We have two 4000 Qtraps and we have been extremely happy with them. They've been robust and very sensitive. On the service end, ABI has been great. The software has some good points and some bad ones (just like everyone else's) but for us it's done fine. Based on our experience, I highly recommend them. (But as always, YMMV!)

[lmh]

Get the manufacturers to run test samples! Be careful to ensure that the manufacturers work in a comparable way (i.e. check they don't give better sensitivity by setting up their instrument in a way that sacrifices selectivity, etc.). And don't forget that the MS is only half the story. You probably don't want a superb mass spec that you could only afford because it came with a dreadful LC system, or vice versa. Good luck!

[Ron]

This isn't just three different systems, it is three different technologies. The best thing to do is to see what others in the field are doing. If they are reporting high resolution mass data, then the Q-TOF is the only instrument that will work. If all that is needed is fragmentation without high mass accuracy then either the QQQ or Q-Trap will work. If you decide on the technology you need then the instrument choice is easier.