Liquid Chromatography

In this instalment of HPLC solutions , I’d like to share a few of the places that I look when confronted with a new separation problem.

This is the fourth instalment of HPLC Solutions related to resources you should have at your fingertips when you are working in an HPLC laboratory (see also #130,131,132). In the last discussion (#132) we looked at online resources from the...

QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) is a sample preparation technique used primarily in the food industry to extract and clean up samples for instrumental analysis. Originally, the QuEChERS approach was developed for multi-residue...

A reader wrote to ask why he was seeing such a difference in the appearance of a gradient chromatogram when all he did was change the flow rate. He’d been making similar changes with isocratic methods for years – an increase in the flow rate...

In the last instalment of HPLC Solutions (#74), we looked at the gradient proportioning valve (GPV) test as a tool to check for proper operation of the proportioning valves used to blend solvents in low-pressure-mixing HPLC systems. The test...

If you have a low-pressure-mixing system on your HPLC, the solvents are blended using a proportioning valve. Usually this mixes up to 4 different mobile phase components. The pump delivers at a constant flow rate, for example, 1 mL/min, and the...

Last week (HPLC Solutions #72) we looked at how in-line degassers work. This week I’d like to look at an interesting case study related to the degasser that was contributed by a reader (WLT). The story goes like this: I am running a gradient from 0...

For the first part of my HPLC troubleshooting career, it was very easy to name the number one HPLC problem – degassing. Air bubbles in the pump were a headache for nearly every user. Helium sparging was the gold standard in degassing, but was...

In this article the selection of appropriate robustness factors and factor levels relating to the mobile phase will be discussed and in particular, the volume fraction of the organic solvent in the mobile phase for reversed phase HPLC.

Want to get a better understanding of the various sample preparation procedures available for GPC/SEC analysis, and what to consider when selecting one? If so, this tutorial is for you...

One question we regularly receive is regarding porous-layer bead packing materials. Are these for real or are they just hype? Let’s take a look at some of the characteristics of these column packings and see what lies between the frits of the column.

Shimadzu has announced the release of its “Advanced i-Series” liquid chromatographs meeting user demands for analysing a large number of samples or quickly re-processing data even when working from home.

This webinar shows you how to return to a productive laboratory operation in the new normal working environment. Covid-19 has affected us all and the positive impact that your asset management strategy can have on the productivity of your changing...

In this on-demand webinar, the advantages of the ACQUITY PREMIER columns are highlighted and the various particle technologies and their benefits in chromatographic separations discussed. Register for the on-demand webinar and see what you've been...

Would you like to pick up valuable troubleshooting tips and insights into ion chromatography and its many advantages. If so, this on-demand webinar will provide the answers.