Chromatography Forum

Hi All,

I am looking to purchase an HPLC-MS for my organic synthetic group. We are mostly interested in following reactions' progress and sometimes in quantifying products.

So far I have two options in mind:

Agilent:
Base pack: Agilent G6125B LC/MSD with ESI Source, mass
range from 10- 2000 amu, with selection valve,
Pos/Neg switch, and Infinity II Series LC modules,
G7111B Quaterary Pump, G71114 VW Detecor –
replaced by G7115A DAD, G7129A Vial Autosampler,
Lab OpenLab ChemStation SW, PC and monitor, Image
recovery service included. Also includes: M8500AA
Instrument Driver for Agilent LC M8360AA OpenLab
CDS 3D UV (PDA) Add-on M8362AA OpenLab CDS CS LC
3D MS Add-on.

Modifications added
1.Substitute 1260 Infinity II DAD for VWD
2.Multimode ESI/APCI Source

Shimadzu:
- LC2050C 3D integrated HPLC
- Quaternary pumping system - Cooled autosampler
- Column oven
- PDA detector
- LCMS-2020 Single-quadrupole mass detector with DUIS dual ion source
(ESI and APCI)


Which one seems the best?

Thanks,

K.

A side question: do you absolutely have to have a multimode source? Might be an outdated opinion at this point but haven't heard anything good about them, it's not that difficult (at least on an Agilent MS) to switch out the source types and have two separate sources.

Granted, in cGLP facilities the separate sources can be treated as separate pieces of equipment that your QA people may make you do IQ/OQ every time you trade them out ...

Idk, my point is if the choice is between a multimode source (that does both but neither as well as a dedicated source) or two separate sources I'd pick two separate sources if the choice is purely convenience. Unless it's a cost thing too, but I doubt it. The ESI source would come standard and buying an APCI source I would think would be cheaper than "upgrading" to a multimode source right off the bat ...

Thanks for your advice!

It’s pure laziness in our case. We never have sensitivity issues really… all the opposite, students tend to inject too much.

The Shimazu DUIS source is strange. It claims that it can record both ESI and APCI at the same time!

Single quadrupoles are simple and robust instruments and any brand should do the job in your case. Thus, the software, guarantee terms, after-sale service etc. will probably be more important than the hardware itself.

One option you may still want to consider is the QDa from Waters, which is a small quadrupole integrated in a UHPLC system that according to some colleagues seems to work well (we don't have any in our lab yet). I have no clue about prices but this might be a way to get a UHPLC-MS system for the price of an HPLC-MS. I guess there is no APCI probe available, though, only ESI compatible.

I did consider Waters qDA. Our MS department has a few Waters instruments with QDAs and they are all dreadful... The waters engineers are non stop on site fixing them.

I did consider Waters qDA. Our MS department has a few Waters instruments with QDAs and they are all dreadful... The waters engineers are non stop on site fixing them.

We are considering waters qda so may I ask if you know what type of problems they have observed in your ms lab? Is it the qda or the lc that give problems?

For us the lc system I-Class, H-Class and QqQ ms from waters have worked well so far. The capillaries are very narrow in the lc so particles can cause problems.

Hardware wise I think either the Shimadzu or the Agilent are good systems. I have run more Agilent so I find their maintenance easier, but the Shimadzu might also be easy if I did it more.

I always did prefer the Agilent software though. It just seemed more intuitive.

The one I avoid, but many like, is Thermo, because of the Chromelion software. We had one for a while and I never could adjust my thinking to match the logic of that software.

I would also vote for the two separate sources. If one breaks then you can always run experiments in the other mode, with the dual source you loose the ability to run at all if something happens with the source. Also the separate sources are probably easier to clean and maintain than the dual mode ones.

I did consider Waters qDA. Our MS department has a few Waters instruments with QDAs and they are all dreadful... The waters engineers are non stop on site fixing them.

We are considering waters qda so may I ask if you know what type of problems they have observed in your ms lab? Is it the qda or the lc that give problems?

For us the lc system I-Class, H-Class and QqQ ms from waters have worked well so far. The capillaries are very narrow in the lc so particles can cause problems.

We have open access QDA UPLCs and they are properly useless... We can't see anything and the only way to see something would be to select an ion to observe... Which defeats the purpose of identifying unknowns!

I guess these UPLC QDA are getting dirty all the time and our mass spec guys are relying on Waters' engineers to come and fix the issues all the time...

I guess it works well if you keep injection quite clean mixtures, which is not always the case with organic chemists.

I did consider Waters qDA. Our MS department has a few Waters instruments with QDAs and they are all dreadful... The waters engineers are non stop on site fixing them.

We are considering waters qda so may I ask if you know what type of problems they have observed in your ms lab? Is it the qda or the lc that give problems?

For us the lc system I-Class, H-Class and QqQ ms from waters have worked well so far. The capillaries are very narrow in the lc so particles can cause problems.

We have open access QDA UPLCs and they are properly useless... We can't see anything and the only way to see something would be to select an ion to observe... Which defeats the purpose of identifying unknowns!

I guess these UPLC QDA are getting dirty all the time and our mass spec guys are relying on Waters' engineers to come and fix the issues all the time...

I guess it works well if you keep injection quite clean mixtures, which is not always the case with organic chemists.

We have a Shimadzu 2040C 3D and LCMS-2020 with DUIS in our lab and we've never had issues. We are quite happy with the system, as we use it for forensic applications and there's nothing better than having to run a single scouting gradient for 99% of the analytes we see.

I did consider Waters qDA. Our MS department has a few Waters instruments with QDAs and they are all dreadful... The waters engineers are non stop on site fixing them.

We are considering waters qda so may I ask if you know what type of problems they have observed in your ms lab? Is it the qda or the lc that give problems?

For us the lc system I-Class, H-Class and QqQ ms from waters have worked well so far. The capillaries are very narrow in the lc so particles can cause problems.

We have open access QDA UPLCs and they are properly useless... We can't see anything and the only way to see something would be to select an ion to observe... Which defeats the purpose of identifying unknowns!

I guess these UPLC QDA are getting dirty all the time and our mass spec guys are relying on Waters' engineers to come and fix the issues all the time...

I guess it works well if you keep injection quite clean mixtures, which is not always the case with organic chemists.

Thanks for the usefull info! We will certainly make sure to run test samples before any purchase.

Thanks for the info. Sounds like the noise of the TIC/BPI on the qDa is very high. Could either be due to a very dirty system (as you mentioned) but also to the propensity of Waters to build systems which now provide a lot of signal but also a lot of background noise. The dynamic range of extracted ion chromatograms is not affected but indeed you don't see much in the TIC. We have the same issue on the last-generation Synapt XS QTOF (while it was not the case on an old QTOF). There are ways to solve this sort of issue (blank substraction, peak picking software etc.), but that's clearly not what you expect for organic chemists who just want to see a peak.