This month we move on to the next section.
Part 3: Equipment:
It is important to list everything needed to perform the analysis, but nothing more. Maybe you did the development on a diode array detector or mass spectrometer. If that equipment is needed then, of course, it must be listed, but if you are not using the diode array's (spectral) capabilities, then an absorbance detector would be acceptable. If you think other users are likely to have a different detector type, you should consider at least a short evaluation on that type of equipment before completing the method.
Also, remember that different detector designs will have different performance characteristics and settings, so make sure your instructions will have enough information. For example, a diode array allows you to set the collection bandwidth; an absorbance detector does not. If you want to use an absorbance detector later, then do your diode array development with a small bandwidth (2 or 4 nm).
Finally, different manufacturers will have different names and settings available.for their instruments. Make your instructions as simple and generic as possible.
Do:
- Include the type of instrument and general capabilities (e.g.., HPLC with gradient capabilities, GC with split/splitless injector, etc.).
- Include the features/modules required, but not anything extra.
- Include all instrument settings, remembering that there may be some differences in settings and terminology between different manufacturers. (More on this in the operating parameters section.)
Do Not:
- Specify a single instrument manufacturer and model unless the analysis must be performed on that exact model of equipment.
- Develop a method that uses the special features of one manufacturer, unless that is the only way to produce acceptable results. The manufacturer can brag about their unique capabilities, but you should not.
- Do not use the "or equivalent" option for an instrument. This statement has very little meaning. List the capabilities needed as noted above. That will be enough.
Next Month: Columns
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Learning Method Development
One of our most challenging and rewarding activities is teaching method development to chromatographers. However, there is a perception among many people outside of the field that you learn method development by going to a class (preferably it is free and only a half-day long!), and then you are an expert on method development.
If only that were true! Unfortunately, we cannot transfer 30 years of experience to someone else in just a few hours, or even a few days.
Learning method development is much like getting directions for a trip from Google or your phone. I like to just look at the map to get a general idea of where I am going, and then get more specific help when I need it. Others like a step-by-step method, with everything planned out in advance.
The only problem with the step-by-step method is that we do not always know when there is road construction, a new or closed road, an accident, or an incorrect map. So it is with method development. The best plans and directions are only useful if there are no unexpected problems or limitations, but there always are!
You are successful in method development because you understand your goals and the tools that you have to reach those goals,
not because you "understand method development."
“Science is not a result, or an outcome, but more a way of traveling, a method of operation, a way of thinking, a process.” – Thomas Edison
We now have several method development classes, developed in cooperation with CHROMacademy.
Maybe we can help your lab also. Contact us for details. |
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Quote for the Day
"Without multivariate data analytic tools, the scientist will perceive the stream of data from the multi-channel instruments as annoying cacophony rather than sweet music. Consequently, they will play fancy new analytical instruments the good old way — one string at a time. For instance they may choose to use only one of the available wavelengths or chromatographic peaks, ignoring the rest in order to avoid getting flooded with data. This forces the user to ignore a lot of potentially important information."
– Harald Martens and Tormod Naes, Multivariate Calibration,Wiley, New York, 1989, p. 23
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Vendor Seminars
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The following courses are offered by Agilent Technologies at their Atlanta, GA training center.
Infinity HPLC Maintenance and Troubleshooting
April 15 - 16, 2014 (seats available)
June 17-18, 2014 (seats available)
Learn how to maintain your 1220, 1260, and 1290 instruments.
HPLC OpenLab ChemStation Operation
July 15 - 18, 2014 (seats available)
Learn all the features of this new software program in a hands-on setting..
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Contact Us
Merlin K. L. Bicking, Ph. D.
ACCTA, Inc.
P. O. Box 25602
Saint Paul, MN USA 55125
Email: info@accta.com
Internet: www.accta.com
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