What’s the Difference Between Superficially Porous and Totally Porous HPLC Columns?

by Lee Polite | Aug 19, 2025

Let’s do a deep dive into HPLC particles. Specifically, the difference between totally porous and superficially porous materials—and why it matters for efficiency and pressure. Quick Answer: SPS vs TPS in HPLC Totally porous HPLC particles provide large surface area...

Co-Elution: The Achilles’ Heel of Chromatography (and What You Can Do About It)

by Lee Polite | Jul 3, 2025

Chromatography is the most widely used analytical tool in modern chemistry. Whether it’s gas chromatography (GC) or high-performance liquid chromatography (HPLC), nearly every chemical analysis in the world today depends on one of these techniques. But there’s one...

Understanding the Master Resolution Equation: Your Key To Easier Method Development & Troubleshooting  

by Lee Polite | May 22, 2025

For any chromatographer, whether seasoned or just starting, the ultimate goal is to achieve good separation between analytes. This separation, known as resolution (Rs), is not a matter of chance but can be understood and manipulated through a fundamental relationship...

Negative Peaks in HPLC Refractive Index And UV Detectors

by Lee Polite | May 13, 2025

RI detector showing negative peaks? It’s not a mistake! Most of us in the lab are pretty familiar with the sight of a good, strong positive peak on our chromatograms. It’s what we expect, right? But every now and then, especially if you’re working...

Reference wavelength, Peak Purity, and Threshold – Diode Array Parameters and Tools.

by Lee Polite | Mar 24, 2025

Understanding Reference Wavelength in Chromatography If the reference wavelength is activated, should the spectra range include the reference wavelength too? If not, what will happen? I’m going to walk over to my laptop and open ChemStation to answer the...