Dwelling on the Fundamentals
The next generation of chromatographers risks losing sight of basic principles
Victoria Samanidou |
I was reading an interesting article by Tony Taylor about dwell volume (1) when an uncomfortable thought struck me – how many of my chromatography students would actually understand this?
The article discusses whether the concept of dwell volume is still relevant, given the proliferation of UHPLC, and the fact that extra-column volumes are much reduced. Taylor writes, “I’m sure most of us are aware that dwell volume is the volume in our HPLC system from the point at which eluent solvents are mixed to the head of the packed bed within the column.” Again I pondered: would “most” of us know that?
As chromatographers, we know that resolution relies on selectivity and that dwell volume can affect resolution and selectivity in HPLC methods... But how efficiently can young chromatographers handle selectivity in terms of column chemistry (stationary phase) and mobile phase constituents?
Young scientists may be able to use an Orbitrap LC-MS instrument, both hardware and software. They may be experts in knowing how to collect and interpret data, or how to apply chemometrics. But if one asks a simple question about the basic principles of chromatography, many of them cannot give a decent answer.
The same chromatographers may not know that C18 columns are not all the same, and that manufactures may produce several different types. They may have never paid attention to carbon load or surface area when choosing the analytical column, concentrating only on length, the inner diameter or the particle size.
With regards to mobile phases, do they know why methanol and acetonitrile –although both polar – lead to different eluotropic strength? Does the Snyder solvent selectivity triangle (2) ring a bell? What is the role of TFA, or ammonium acetate in the mobile phase? Why is water not enough? These and many other fundamental aspects too often leave them drawing a blank.
Going back to the initial question – how many know the meaning of dwell volume and how to measure it? How many of them have actually measured it in the instrument they are using? When developing gradient methods and transferring between different high-performance instruments, have they taken into consideration this very important issue?
My point? All HPLC practitioners should be able to answer these types of questions; being able to use highly sophisticated instrumentation in routine analyses is not enough. Not so many years ago, students were at least aware of the theoretical principles of chromatography.
It seems to me that this drop in fundamental knowledge is a reflection of wider changes in education (3). Core education is overwhelmed by the tremendous evolution of technology. The new doors (or rather, the new “windows”) that technology opens sometimes lead to a sacrifice of crucial basic education. Undoubtedly, the younger generation rely too much on easy access to knowledge online, and so fail to assimilate the basic principles and theoretical aspects of the techniques they practice.
Virtual reality, virtual knowledge, and finally virtual education, have become part of our lives. My final question: can we stop or reverse the trend, before it is too late? At the very least, we have to give it a try.
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- LCGC, ““Dwell volume - still relevant in our UHPLC world?”, 2017). Available at: bit.ly/2gdlIj8, Accessed October 5, 2017.
- Crawford Scientific, “Going back in time – ternary and quaternary gradients”, 2017). Available at: bit.ly/2fT1YEr. Accessed October 5, 2017.
- Infogineering, “The difference between data, information and knowledge,” (2017) Available at: bit.ly/1wrG75E . Accessed October 5, 2017.