Incognito suggests that chromatographers are not exploring the full potential of their “state-of-the-art” instruments.
Photo Credit: bondvit/Shutterstock.com
Incognito suggests that chromatographers are not exploring the full potential of their “state-of-the-art” instruments.
Several years ago, I had the pleasure of visiting Monaco, a beautiful and very opulent principality on France’s Mediterranean coast. It’s best known for casinos, the Formula 1 Grand Prix, and, of course, Grace Kelly, who became Princess Grace of Monaco after marrying Prince Rainier III in 1956. It is also a tax haven.
While I was there, amongst many other supercars, I spotted a 2010 Ferrari California in the famous Rosso Corsa red, with the 4.3 litre V8 engine, which takes it from 0–62mph in less than 4 s and achieves a top speed of around 193 mph. It’s a breathtaking vehicle and was perfectly situated in the bright sun and lavish green palms on the cliff tops above the harbour.
The speed limit in Monaco is 31mph-everywhere.
So why own a Ferrari California when you live in Monaco? Because you can. You can’t go fast (the traffic enforcement is very stringent) but you can, in theory, cruise in great style. And, of course, you may drive outside of Monaco occasionally, which would allow you to take advantage of those eight cylinders and experience the sheer force of being punched in the back by 358 lb-ft of torque. The slight drawback of the California is that it’s a short wheelbase, and as such, not very comfortable for tall folks, so you may only want to take it out occasionally to avoid compressing your spinal cord.
My point? Well the California reminded me very much of laboratory instruments and the way in which we often buy equipment and never get to use it to full effect. We are effectively “performance limited” by the speed regulations in the laboratory, which include: the requirements to get the kit up and productive as soon as possible; the instrument capabilities never being fully explored because of workload pressures; and a lack of knowledge of how to get the instrument performing to its best. This means that high cost, high specification equipment is performing way below its capability on a day to day basis-just like the Ferrari in Monaco.
I’ve gathered many examples of this phenomenon over the years and I hope that the following examples spur you into thinking about how you might get a little more out of your own Ferraris (and some of the equipment in your laboratory may well cost more than the £150,000 that you’d pay for a California).
Let’s start with ultrahigh-pressure liquid chromatography (UHPLC); even though most systems will consistently run at 1000 bar, few of us operate our systems at anywhere near top pressures or flow rates. I often wonder why this is, and I think there are several factors in play, perhaps foremost of which is habit. For most laboratories moving into UHPLC, you will have been used to operating at much lower pressures and as such will have been used to having to trade flow for back-pressure limitations. This attitude will be carried over to your new equipment. Second, you must have a reasonably long column packed with very small particles operating at higher flow rates to reach the pressure limit of most UHPLC systems. This is going to generate a very high amount of theoretical plates and, frankly, a performance that many separations just don’t need. To make use of the full performance, we’re going to need to find out more about what column dimensions are suitable, what flow rates can be achieved, and ultimately change our attitude to operating at much higher pressures than we have been used to. We may also need to consider the suitability of the column end fittings and map out any changes in the back pressure during the course of our gradient analysis as the eluent viscosity changes in case we overpressure the instrument. We may need to make sure that our detector settings are correct to cope with the very narrow peaks generated and perhaps redevelop our integration algorithms. The simple question is: Why don’t we take this approach from the start? Drive the California as it should be driven? Well perhaps that’s something you can answer for yourself and even consider the methods you might want to improve and “drive” a little harder. That’s if you have the budget for another new column, the time, and an inclination to tinker.
I also see many users, especially when using gas chromatography–mass spectrometry (GC–MS), adopting the autotune routine to tune the MS, source, and detector voltages-the argument often being that these things bring “continuity” and regulatory comfort. With only a little knowledge, it’s possible to identify how to manually tune these voltages and attain much better resolution and sensitivity for the application you are running than the autotune routines, which are generally designed to make the instrument perform “well” for the general population. Once again we’re driving a Ferrari around Monaco, without taking the time to learn new skills to make full use of the instrument’s performance.
How many times do I see PTV inlets on GC instruments languishing unused on the instrument? These inlets are more difficult to setup and optimize with many more variables than a standard split or splitless injection, but the performance benefits, especially for trace analysis, are enormous. We don’t take the time or make the effort to learn how to drive the instrument to its full capacity-or in this case the California is left in the garage!
There is so much we can do with temperature in high performance LC (HPLC) to improve the performance of our separations. Most instruments today have very sophisticated temperature control capabilities and even have pre- and postâcolumn eluent temperature control. Yet we are troubled by the additional complexity this brings to method development, worried about the pH limits of our silica columns at elevated temperatures, and nervous to venture into exploring variables that are usually untouched.
Data systems are also terribly underutilized. They can control instrument variables that you may not even be aware of (pressure or flow ramping, pump ripple minimization) and can be set up to automatically build calibration tables, report against limits for system suitability checks, check integration, report sample results, and automate QC checking. Yet how many of us still use spreadsheets to calculate results because we can’t get the data system to produce the results in the way we want or believe that it is not possible? Most of the time it’s simply because we don’t have the time or knowledge to set the data system up properly and again we are travelling at 30 mph in our gleaming red Ferrari.
As I said earlier, we get ourselves in these situations because the time and pressures of work don’t allow us to break free and learn how to drive the instruments and software to their fullest extent. They work OK for us, we can manage. But the argument is cyclical-without learning to improve performance and increase automation, we’ll never get time for ourselves to “explore” the capabilities of the stallions in our stable.
All I can ask is that if you suspect there is a Ferrari lurking in your laboratory, straining to get beyond those city limits, jump in and start exploring what it feels like when you really put your foot down.
Contact author: Incognito
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