Dear ABRFers,
I am concerned about misleading information distributed to this forum.
In one of the messages regarding nano-LC instruments, it was stated that MicroTech offers the same autosampler as LC Packings and Waters. This is simply not true.
LC Packings indeed has an OEM agreement with Spark for the production of the Famos autosampler. But this autosampler contains patented technology which is proprietary of LC Packings (US Patent 08/729388). These technologies are only available for LC Packings and Dionex.
Have a nice Easter time !
Best regards,
Emmanuel
----- Original Message -----
From: Ombudsman account for AECOM
To: Recipients of ABRF List
Sent: Wednesday, April 04, 2001 10:45 PM
Subject: Follow-up to e-mail below (fwd)
Sir/Madam:
I would like to post the following blind response to the e-mail below (I am new to this, but I believe it is possible for this to become a "thread" to the previous dialog):
---------------------
The information posted below is certainly comprehensive as applies to the primary vendors addressed, including HP (Agilent), Waters, LC Packings, Michrom and Eldex, and thanks are due to Dr. Vensel for taking the trouble to put this useful information together. However, in the interest of completeness, it may be appropriate to add a few additional comments about the product from Micro-Tech Scientific, to supplement the single comment below, based on the capabilities of their newest system.
The Micro-Tech product is unusual in that, unlike the other reciprocating-piston based pump systems, it is capable of delivering extremely accurate flow rates without splitting (100nl per minute isocratic and 2ul per minute gradient, both with RSD <0.5%). This allows the product to be run in a constant-flow mode versus constant pressure mode, making the system less susceptible to flow changes due to routine usage. If desired, the system can also be run in a split mode, generating accurate and reproducible gradients in the low nanoliter per minute range. The system also exhibits extremely low dead-volume, the total of which is only 8ul between the pump heads and the injector.
Micro-Tech also uses the Spark-Holland OEM autosampler (the "Endurance"), which is the same product used by both LC Packings (now Dionex) and Waters on an OEM basis, due to its excellent performance for very low sample injection volumes and reproducibility.
As mentioned in the single feedback on Micro-Tech, they now offer as standard a configuration that allows for facile two-dimensional gradient protein analysis, with optimized software for the same. The Micro-Tech may be the only commercial system to do this.
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(Original Message)
From: Association of Biomolecular Resource Facilities
[abrf-request@aecom.yu.edu] on behalf of William H. Vensel
[vensel@attglobal.net]
Sent: Saturday, March 17, 2001 5:39 AM
To: Recipients of ABRF List
Subject: Nanoflow HPLC for LC/MS___RESPONSES
Hello,
Here are the responses that I received Re:Nanoflow HPLC for LC/MS.
I have tried to sort the responses according to the instrument type. Thanks
to everyone for their observations.
Bill
Agilent Michrom: I just had a capillary system from Agilent (nee
Hewlett-Packard) installed. I think it's easier to use and more robust
than the Michrom 2002 I had purchased previously.
Agilent: am using an LCQ instrument in my lab connected to a HP 1100
HPLC from Agilent Technologies and I am very pleased with the results both
in nanobore and microbore chromatography. However we use reverse phase HPLC
all the time: I do not have experience with ion exchange on this instrument.
Agilent: We have had tremendous success using the Agilent Cap LC system
couple with LCQ DECA. It gives excellent gradient separation down to
1ul/min. The flow can be easily split to give beautiful gradients at
nanoliter if need be. We are currently running at 2-5ul/min with standard
Finnigan ESI head and are getting data equivalent to what we have
experienced with nanospray head and nanoliter flow rates. Another plus of
the Agilent Cap LC is that you can also plumb the system to a max flow rate
of 2.5 ml/min if you want to use the HPLC for other preparative uses.
Agilent: You won't need a detector...I'd take that out of your equasion
right away...just flow directly into the MS from the col. I'm looking into
the same thing so I may email you in a week or so to see if you recd any
good replies. So far I'm leaning towards using my HP1100 and spliting the
flow....I just ordered all the tubing and T from Upchurch
Scientific......I've heard that HP (actually Agilent now) has a new, micro
flow pump good to 1-2 ul/min. The ABI ceramic pump (on the blotter and the
CLC Procise Sequencer) is good to 4 ul/min. Most people I know use
splitters...
ALL Systems: I have used both and put simply, they both work fine. so
does the abi 1040c, and so does the hp1100. or whatever they are both
called now. we also have a waters caplc, which had serious enough issues
to get replaced and we havent evaluated the new one yet. we also have
several finnigan surveyor systems - one of them is terrifically good, one
is absolutely terrible and the pumps are still full of junk after several
months, one is average. The LC packings software (ultichrom) is very badly
designed but very useful once you work it out, especially the step-by-step
programmable injection routines. The Xcalibur plugin for controlling the LC
packings system still does not work, after many months of beta testing. If
they ever get that ironed out it would make the software much easier to
use. I would suggest that you make sure that whatever pump you buy is
controllable from within xcalibur, then you only have one piece of software
to go wrong rather than two.and dont forget that the hplc dpoesnt
necessarily need switching valves, you can always buy electronically
controllable injectors/switching valves separately (upchurch?) and control
them from xcalibur.
All Systems: we are running a LCPackings equipment, full with
Famos/SwitchosII/Ultimate, for 75 um columns. The system works fine, there
are some smaller drawbacks, like the communication with the computer
sometimes fails, but nothing really to complain about. The reproducibility
of the flow looks nice, as nice as with 150 - 200 nL/min one would expect,
the sensitivity is excellent, even if the detector sees nothing we get good
MS/MS spectra. I can really recommend this equipment. Even using the
autosampler over a weekend, only two failures occur, and I ahve to find out
why, but no run was lost. The program is a little old-fashioned, some
things I donot like, like filling large run tables, but this is only a
minor part. There is only one thing, we ordered some time ago a second
equipment - so you see we are happy with it - and I am waiting.... Due to
the change of LCPackings to Dionex, nothing works as it should be, tomorrow
I will get a notice when my instrument will come, two weeks after the
deliver date originally announced. So I will look also at the Michrom
system next week, and I will get an AGILENT 1100 to test with 75 um columns
and I will see what Waters CAP LC can do, as there are some ideas bout low
nano-flow rates. Because of a little uncertain situation with LCPackings I
do this, otherwise I would equip all my systems with LCPackings. I think
their specs are fullfilled completely. we are running a LCPackings
equipment, full with Famos/SwitchosII/Ultimate, for 75 um columns. The
system works fine, there are some smaller drawbacks, like the communication
with the computer sometimes fails, but nothing really to complain about.
The reproducibility of the flow looks nice, as nice as with 150 - 200
nL/min one would expect, the sensitivity is excellent, even if the detector
sees nothing we get good MS/MS spectra. I can really recommend this
equipment. Even using the autosampler over a weekend, only two failures
occur, and I ahve to find out why, but no run was lost. The program is a
little old-fashioned, some things I donot like, like filling large run
tables, but this is only a minor part. There is only one thing, we ordered
some time ago a second equipment - so you see we are happy with it - and I
am waiting.... Due to the change of LCPackings to Dionex, nothing works as
it should be, tomorrow I will get a notice when my instrument will come,
two weeks after the deliver date originally announced. So I will look also
at the Michrom system next week, and I will get an AGILENT 1100 to test
with 75 um columns and I will see what Waters CAP LC can do, as there are
some ideas bout low nano-flow rates. Because of a little uncertain
situation with LCPackings I do this, otherwise I would equip all my systems
with LCPackings. I think their specs are fullfilled completely.
Eldex: I have been quite happy with my Eldex pump, which we now have
running w/ a Qtof. It is not computer controlled -- just a key pad on the
front. However, their are a number of contact closures available for
recieving and sending of signals. It does 1 ul/min w/o splitting, although
I run it at 5 ul/min to split down to .25 ul/m. The only problems I've had
were that the syringe pump seals occasionally spring a leak, and over the
course of several years I've had to replace them twice. The thing is
really simple to use and fix. Last I checked the dual syringe pumps go for
$21k.
ELDEX: xxxxxxx is the only person I have ever heard say anynthing ogod
about the Microtech. I would suggest you look at the Eldex MicroPro pump,
which can do gradients down to 1 ul/min (we have one), and also at LC
packings. When we chose the Eldex over the Microtech, Jan-Pierre Salzman
of LC packings told us that was a good decision. We demoed the microtech;
the pump has six check valves. The Eldex has only two.
LCPackings: I have been enjoying the LC Packing system, FAMOS plus
ULTIMATE, in conjunction with an LCQ Duo. It has been performing very well
at 4 uL/min flow rates using their 0.3mm id column using the conventional
ESI source for online tryptic peptide mapping at the low pmole level. The
system has been robust and customer support has been real good. Cannot say
about nano-dimension yet because I am not yet there but will be soon.
LcPackings: I have the LC Packings instrument for two years. It has been
very reliable and the support has been good as well. The software has
some annoying quirks/features but then what software is perfect. I can
unabashedly recommend the Ultimate. I have no personal experience with
the Michrom. I have a colleague who uses it for capillary LC and is very
happy with it at those flow rates (microliter/min range).
Michrom: Only Michrom Exp... Great Support, great chromatograms, love the
minimal col/det dead volumes, Kerry Nugent at Michrom is one of the best
chromatographers around, simple, easy to work-on, have not used the latest
model. People crushed too hard on my old purge valve and that was about
the only problem I ever had with it. Got parts in one day and put them in
with plenty of phone support and the inst was hardly down. It was simple
and fun to use. But no exp with the ASampler.
Michrom: Our lab has two Michrom HPLCs. One is for peptide purification
and the other is coupled to an LCQ classic mass spectrometer. The HPLC
coupled to the LCQ is the Magic 2002 and has been in place in the lab for
about 4 years. It is always operated at the 50 to 600 nL/min range and is
heavily used for RP separations of peptides produced from proteolytic
digestions. The Magic 2002 system has been very reliable and fairly easy
to operate. I do not use the UV detection system that came with it since
the LCQ is the detector nor do I use the injector (I use pressure
injections from a bomb). As far as the pumps are concerned, I feel that
they are very good. With the heavy use on our HPLCs, we find it necessary
to have
Michrom rebuild the pumps about every 1-2 years ($700/pump). The software
that controls the instrument is also good. It is very stable and has never
crashed on me. I don't really do anything fancy with the software except
use it to control the pumps and create gradient programs (in other words,
I am not collecting UV traces with it). It is also important to note that
the Michrom sales and service staff is excellent. Their trouble shooting
skills are superb and someone has always been available to help me when I
call. There is one feature of the Magic 2002 system that I find annoying.
The entire system operates under helium pressure. The wash solvent and
both LC solvent containers are under helium. Of course, the helium helps
minimize dissolved oxygen in the solvents, but it also helps maintain the
flowrate (or so I am told). I have never used an HPLC which has this
feature and it has taken me many months to get used to it. If you
purchase this system, you will have to install a helium line to your new
HPLC and hope they you never develop a leak in the system. If you will be
changing solvents frequently, this helium pressurization might drive you
crazy. Once the solvent bottles are cracked and opened, you must make
sure you get a good seal when you close them and wait for the helium
pressure to build in the bottles. This can sometimes take a while. I am
not sure if others find this feature as annoying as I do, but I feel it is
the biggest drawback of this HPLC. Also, the wash solvent is pushed
behind the pumpheads while the instrument is running using the helium
pressure. It has been very hard for me to get reasonable wash flowrates.
Sometimes I go through the wash solvent in 4 days, other times I go
through it 2 months. I have no idea how to control the washing rate.
Michrom: We are actually selling a Michrom Magic 2002 which is a year old
and has hardly been used. Do you have an interest in it?
Michrom: We have a Michrom that we purchased for nanoliter flow and we are
very unhappy with it. Others like it just fine for higher flow. We
experienced a pulsed flow that made microspray very difficult. We also had
problems with our pump heads and tremendous software issues. Their software
is not up to speed with current computers and this will cause you many
headaches. I believe the LC packings pump has a pulse dampener and the
Michrom does not. Hope this helps.
Michrom: We have not been very happy with our Michrom. It had to be
rebuilt several times and the customer support was not very good.
Michrom:; We have been VERY unhappy with our michrom on our classic LCQ at
the low flows required for microionspray. We have an eldex pump that works
just great and is cheap. Tell them both we said so.
Microtech and Waters: Have you considered Microtech Scientific or
Waters? Both have capillary HPLC systems. We have four systems here: a
Waters 600MS that we split for capillary columns and infuse into our LCQ
Classic; a Microtech that was connected to an LCQ Deca, a Waters CapLC that
is being connected to the LCQ Deca; and a Micromass CapLC connected to our
Q-TOF.
MicroTech: Another vendor of microbore/capillary HPLC is MicroTech. They
had a demo of an ion exchange/RP set up for tryptics at the recent ABRF.
Other: I am glad that you are going to post the responses. We aren't
ready to move up in throughput yet, but discussions to buy a commercial
system have begun in my Core lab. Now we use the Davis/ Lee mspray/ nspry
interface on our 3 LCQs for our protein ID operations. Good Luck to you!!
Waters/Micromass: We've also seen Fe contamination in protein and peptide
samples when using the Waters/Micromass CapLC. Apparently enough people
have the same problem that Waters is doing a study to determine the source
of the Fe. We know Fe is coming from the CapLC because we've observed it
on our LCQ Deca immediately after connecting the LC.
We are in the process of connecting the Waters CapLC to the Deca for
increased throughput. The Waters CapLC has an autosampler with three
injection modes of which the uL pickup mode is of interest to us. If we
get it running consistently it will be nice but we have had a series of
problems with the pumps and autosampler. The Microtech has served us well.
We ran it at a higher flow rate (10 uL/min) and split it for use with
capillary columns. The Micromass CapLC is basically the same instrument as
the Waters CapLC (go figure) but is better suited for connection to the
Q-TOF (another no brainer). So far the Micromass system is running much
better that the Waters system but we have not used it as much. Time will
tell on that one.
---Emmanuel Varesio, Ph.D. Senior Research Scientist, Proteomics
LC Packings -- A Dionex Company Abberdaan 114 1046 AA Amsterdam The Netherlands
phone: +31-(0)20-683 9768 fax: +31-(0)20-685 3452 e-mail: emmanuel.varesio@lcpackings.nl
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