Okay, I’ve been pushing our company to shell out for some analytical equipment. Looks like a GC method would be great given the great results @bigbone and @Dr_Jebril have been getting with cannabinoid quantification. Plus I’d really like to do OVI Testing in house. There’s a lot of love for SRI here and a million and one Agilent 6890s for sale but doing a little digging it looks like a GC/MS isn’t substantially more expensive on the used market.
So I guess my question for those who know is: why shouldn’t I buy this triple quad?:
Edit: wrong link
It looks nice.
You should ask the seller if it works as it is, and even better if you can test it first (if it is currently in use).
Pardon my lack of MS knowledge but my understanding is its a bit more of a learning curve vs the FID detectors and its overall not as straight forward to test for potency of samples.
I’ll let the more experienced MS guys tell me if im right or not.
Not sure why you would want a Triple Quad for quantification. You can get excellent numbers from a single pole GC/MS - and it will cost you less to maintain (fewer moving parts) and would require less carrier gasses (unless you decided not to use all of its functionality, but then why get a triple?).
If you want to do residual solvent testing - you’re going to want a headspace system (in my experience…) and this machine doesn’t come with those parts, at least they are not listed on the auction.
If I was going to quantify cannabinoids for potency I’d go HPLC. Or even uHPLC - because its FAST and the materials and supplies are cheapish.
If I was going to quantify residual solvents I’d go GC/MS - because the columns are available with established methods that are used in many industries - so you don’t have to reinvent a wheel. Buy a column with a standard set which comes with a method and go go go.
But really - why would I not buy this specific machine? Because that SOB runs on Windows XP, it doesn’t say it comes with the computer OR the collection and integration software. So that means you’ll be very limited on what you can do OR you’ll have to buy that stuff from someone as well. I’d prefer not to have to go back to 2002… but that’s just me.
Pardon my lack of MS knowledge but my understanding is its a bit more of a learning curve vs the FID detectors…
I 100% agree. If you are getting this instrument and have never worked with Mass Spec before OR perhaps never done any analytical chemistry before - this is not the machine for you. The maintenance necessary is much more complicated than newer systems. The method development is more complex. And the spectra libraries - may not even have the things you want in them for this machine. So you’ll have to read that spectra yourself. Lots of learning on the line.
I imagine you like the learning - so if you’re up for the challenge do it. I basically lived with one of these machines for most of 2003 and 2004. They are beasts and get the job done - just be prepared to marry it to make sure you get clean and consistent results.
biggest issue with older varians is the driver support… make sure the computer included with the system can run it!!! ie; has the drivers installed already. it should be a dinosaur of a computer.
I appreciate all the well thought out and detailed replies!
So yes, it’s basically not in my budget to get something that runs on a recent OS lol but I’ve played this game lots of times with other machine tools. If it doesn’t come with original software, it is disqualified and if it does that computer never sees the internet again.
@Cassin you are probably correct that we don’t need qqq and you are also right that my experience running analytical equipment is limited to like 3 classes in college (one of which did include running LCMS but, well, I barely remember what kind of equipment it was lol). So, for my uneducated ass, can’t I just ignore the fragmentation data and just look at the first MS? There are other options for GC/MS with TOF instead of single quad but they seem less ubiquitous so probably even more of a pain to learn.
I am a very very fast learner and good at fixing pretty much anything ever made (not to toot my own horn) but I’m not quite enough of a masochist to look for hard to fix/operate things.
I should also probably mention that we use some solvents which I would like to quantify in the 1-50ppm range which is a bit tough on FID by my understanding but then again, we’ve done fine paying people for that so far
Ha yes off course the triple quad is an overkill if you only intend to do quantification, and not the detection to start with if you are not that experimented in analytical chemistry.
I thought you were already on the hunt for all the unknowns…
You better start with a FID. Cheaper, simpler, and more straightforward !
I mean let’s not get crazy here, it’s not like my secret motivation isn’t to do exactly that and detect all “the other stuff” down to the last thiol. Just… Don’t tell my boss lol.
I imagine I will probably outgrow the first system no matter what and there will always be used chromatographs/mass specs for sale
And for $3200 I can get an ion trap GC/MS of a similar vintage:
Is the functionality of newer units really so much better? Because it all just seems driven by planned obsolescence to me
Is the Functionality of newer units really so much better?
Short answer Yes!
In most cases - the improvements are specific to an easier to use interface plus easier maintenance (fewer moving parts). If you want HPLC you should be able to get a seriously new (aka not 25 years old more like 10…) Agilent 1260 or 1200 as used equipment. Its solid for all those crazy peaks - and will let you know what kind of fractions to take if you want to send off fancy samples for NMR or something.
If you want a GCMS - you can get one from Shimazdu in the same range as this triple quad, with computer/software and support. You might even be able to get a new one (they have crazy end of year sales…and their year ends in September I believe…)
Things I really don’t want to live without on these newer machines.
- GUI that I can train non-chemists to use
- Reporting functions so I don’t have to spreadsheet everything
- Method Security with Password protection
- Auto-injection…manual injection is terrible for too many reasons
- Software integration with many LIMS so I can easily share my data with others in an online portal
- Vendor specific methods - cause they want you to buy the consumables, but then you don’t have to waste too much time on development…
- Consistently available maintenance and change parts - cause really paying 1k for a replacement pump on your 1100 series is just silly.
That’s fantastic, I always assumed new GC/MS would be approaching $100k but with financing at terrible terms (this is how most other equipment is sold).
Most of my focus is on results alone for R&D, so the reporting and interface tools aren’t as much of a concern for me.
I’m pretty much certain that how I’d go about standing up one of these systems would be:
Go out and see the equipment run
Bring it in-house and follow the IOM to a tee
Hire someone who ran and serviced that particular system to come out and do a very simple methods development with me (probably just repeat validation on a method they’ve already used)
Fuck around with it and a bunch of CRMs for a few months
Hire them to come back out to observe an actual method validation