As an R&D Chemist charged with developing the perfect packing method for new LC columns, one of the challenges is finding a packing method that results in a column which not only passes QC specifications but also passes our arduous lifetime analysis. During lifetime testing our columns are subjected to 1,000 continuous injections at 12,000 PSI (a pressure far higher than what most LC operators will ever need- it’s the equivalent of being under 27,680 feet of water!).
You may ask yourself, “Why bother actually doing 1,000 injections at high pressure? Couldn’t one just run the column at high pressures or flow rates and see lifetime degradation?” What many people don’t realize is that the principal cause of column degradation over time are variations in pressure that occur with each individual injection. These pressure ‘pulses’ are unique to each make and model of HPLC or UHPLC, and are controlled by the structure and mechanics of the instrument.
Finding a rugged packing method that can withstand this kind of punishment isn’t easy – and proved especially challenging when developing the packing methods for our 1.8 µm Force columns. Once we finally hit on the right method I was exceedingly (embarrassingly) excited and jumped at the chance to pit our new ‘survivors’ against the competition. Utilizing our lifetime test and two replicates of each column, we assessed Restek Force C18 (1.8 µm, 2.1 x 50 mm) column performance in comparison to similar dimension, particle, and stationary phase columns from two well-known competitors:
From the graph above, you can see that Restek and Brand 1 columns showed excellent ruggedness, and maintained ≥94% of their original efficiency over the course of the lifetime test. Brand 2 column performance suffered however, with one column steadily dropping in efficiency by the end of the test, and the other maintaining efficiency for 250 injections before plummeting, after which peak integration became impossible due to peak splitting.
At Restek one of our core values is pride in our work. Seeing the results of our hard work in R&D and knowing that we can offer these excellent LC columns to customers gives me great pride to be a Restek R&D chemist.
Thanks for checking out my first blog post!
p.s. Our other dimensions and phases of Force columns are just as rugged as the ones I’ve shown you above. If you want to see another one of my beautiful graphs and learn more about Force please check out our overview here: Force Performance LC Columns Overview .