Tony Taylor is Group Technical Director of Crawford Scientific Group and CHROMacademy. His background is in pharmaceutical R&D and polymer chemistry, but he has spent the past 20 years in training and consulting, working with Crawford Scientific Group clients to ensure they attain the very best analytical science possible. He has trained and consulted with thousands of analytical chemists globally and is passionate about professional development in separation science, developing CHROMacademy as a means to provide high-quality online education to analytical chemists. His current research interests include HPLC column selectivity codification, advanced automated sample preparation, and LC–MS and GC–MS for materials characterization, especially in the field of extractables and leachables analysis.
In Defense of Nitrogen as a Carrier for Capillary GC
December 14th 2015There has been much written about the use of nitrogen as a carrier gas for capillary GC. Formerly, to say it wasn’t any good. Latterly to say that it’s pretty good and a better alternative to Helium than hydrogen from a practicality standpoint.
The LCGC Blog: Simple Visual Methods to Assess HPLC Column Performance – and Get You Out of Trouble!
October 12th 2015A client asked me recently for a quick but "as optimized as possible" separation for some monoclonal antibody (MAb) characterization (digest) samples using LC-MS. The samples had been prepared and were awaiting analysis-typical forward planning! Actually his internal analytical department had changed their priority and he was left hanging.
How to Estimate Error in Calibrated Instrument Methods—And Why We Have Stopped Doing It!
August 18th 2015When was the last time you reported your results with an estimate of the error associated with the data? You don’t need to because your method is performing within the levels defined by various agencies and which were confirmed by your validation and your daily QC checks. The person for whom you are producing the data is aware of these tolerances and therefore inherently appreciates the associated precision of the data and can make judgements based on this. Not in the world I work in!
Eight Steps to Better Results from Solid-Phase Extraction
July 7th 2015If you use SPE in your work, then most likely it’s very important to the success of your applications and it’s proper implementation will be key to the performance of your analyses. However, SPE protocols are “variable in quality” (I’ve been as I kind as I can there!) and this variability appears to come from some common issues, misunderstandings and, frankly, ignorance of the mechanisms which are in play.
The LCGC Blog: Why Every Good Analytical Chemist Also Needs to Be a Statistician
June 15th 2015Once you have mastered the terminology and symbology the actual mathematics for the models and approaches used at the level which is useful to practicing analytical chemists is really very straightforward indeed.
GC Temperature Programming—10 Things You Absolutely Need to Know
June 1st 2015Temperature affects not only retention but also relative retention in gas chromatography (GC) and therefore, when we change temperature, we also change the selectivity of the separation. This is true as we alter the isothermal separation temperature, but also as we change the slope of the temperature program gradient.
The LCGC Blog: Troubleshooting Retention Time Issues in Reversed Phase HPLC
May 12th 2015I got into a discussion with a learned colleague recently regarding the relationship between peak height and flow rate in gradient HPLC. We haven't really resolved the discussion, there are suggestions regarding "peak focussing," the number of column volumes in relation to the gradient volume (number of column volumes per minute), increases in efficiency etc.
The LCGC Blog: Four Steps to Troubleshooting an HPLC Problem
April 15th 2015What if we could make the troubleshooting poster on the laboratory wall come to life? What if we could build an engine which figured out the most likely causes of groups of symptoms and offer these up as a prioritised list for folks to work through and give them supporting information on each problem, why it occurred, how to fix it and, crucially, how to avoid it happening next time?
Understanding Electron Ionization Processes for GC–MS
April 1st 2015Many of us use electron ionization (EI) in gas chromatography–mass spectrometry (GC–MS) without a good understanding of the technique and how we might manipulate the process to give more appropriate results or a better understanding of the analytes under investigation.