In Part 1 and Part 2 of this blog series, we touched upon ways ion chromatography (IC) can have more uses in the pharma lab than just for counterion analysis and how it offers a direct approach to polar and ionic compounds that would otherwise need derivatisation to be HPLC or GC amenable.
Teaching an old dog new tricks
IC certainly isn’t a new trick! You could say it’s the old(er) dog as we are now celebrating 45 years of IC. But ion chromatography-mass spectrometry (IC-MS) is relatively new in comparison. IC-MS is well established in the environmental and water markets and in metabolomics, but we are still learning where this technology can be applied and one growing area is pharmaceuticals. The previous blog posts followed the example of organic acids and how other techniques such as HPLC, GC and CE can have downfalls when it came to analyzing these types of impurities.
IC made sense for these types of compounds, but they can elute fairly close to each other and would the sensitivity of conductivity detection be enough? Adding a mass spectrometer was the logical next step.
This latest application note details how organic acids such as butanioc, 2-butynoic and propionic acids can be analysed directly with IC and a single quadrupole mass spectrometer to detect in the µg/L region in pharmaceutical solutions.
Modern IC offers some clever innovations that not only enable IC-MS to be a viable technique but can also make compliance easier.
IC-MS is made possible with suppressed conductivity. The suppressor desalts the mobile phase converting to water. Solvents of choice can then be added post-conductivity detection to enable ionization. The conductivity cell monitors the background as well as the separation so that no unwanted ionic liquids enter the mass spectrometer.
Don’t worry if you aren’t a mass spectrometry expert. The Thermo Scientific™ Dionex™ ISQ-EC™ is a single quadrupole mass spectrometer designed for chromatographers, using compliant software and default settings that take care of the MS parameters for you. If you need more and want to alter MS settings, then you can do that, too. Watch this video for more on this detector.
Using our 45 years of knowledge in electrolytics means eluents can be generated online on the system, you just add de-ionised water, resulting in effortlessly reproducible eluents every time, from day-to-day, operator-to-operator, lab-to-lab, which makes it the ideal technology for the pharmaceutical laboratory. This whiteboard video shows how eluent generation works.
Thermo Scientific™ Viper™ fittings are now available on the Thermo Scientific™ Dionex™ ICS-6000 and Integrion systems. Pre-fitted nuts and ferrules give the perfect connection. Bad connections can lead to changes in peak shape, loss of sensitivity and the risk of not passing your system suitability testing. Why chance it?
So if you are looking for more from your IC, consider mass spectrometry as a routine detector to improve sensitivity and resolving power to solve those challenges when perhaps IC alone wasn’t enough. Oh, and you can now buy your IC consumables online*, more details below.
To learn more about IC-MS and which IC and MS is right for your needs, visit our learning pages here.