How to improve chromatographic performance using ultrapure water
The purity of the solvent used for the mobile phase is one of many factors affecting the quality of chromatographic data obtained from high-performance liquid chromatography (HPLC). A typical reversed-phase HPLC gradient elution requires equilibration of the column to the initial conditions with several column volumes of the weak (aqueous) solvent. Organic contaminants in the aqueous solvent will adsorb at the head of the column and can cause interferences in the succeeding chromatograms, such as massive baseline shifts and the appearance of extraneous peaks. This study illustrates how two different sources of water used as solvent in the gradient elution of a drug mixture affect chromatographic performance over time. The solvents being compared are commercially available HPLC-grade bottled water without total oxidizable carbon (TOC) specifications and freshly delivered ultrapure water with a TOC level of 05 ppb. Comparing the chromatograms of preconcentrated water by analytical HPLC shows that bottled HPLC-grade water contains many more organic solutes than does freshly delivered ultrapure water, suggesting that these contaminating solutes can contribute to baseline variability and poor chromatographic performance when bottled water is used as a mobile phase in HPLC separations.
Best of the Week: What’s New in MS, 2024 Young Chemist Award Winner
March 22nd 2024This week, LCGC International published a variety of articles on the hottest topics in chromatography and beyond. Below, we’ve highlighted some of the most popular articles, according to our readers. Happy reading!
Inside the Laboratory: The Schug Group at the University of Texas at Arlington
March 22nd 2024In this edition of “Inside the Laboratory,” Kevin Schug, PhD, a full professor of chemistry at the University of Texas at Arlington, discusses his laboratory’s group work in environmental monitoring around water and soil quality near oil and gas extraction, using techniques such as liquid chromatography (LC), gas chromatography (GC), supercritical fluid chromatography (SFC), and coupling these techniques with mass spectrometry (MS).
Cloruson and Related Substances Studied Using Original Ion-Pair UHPLC Method
March 19th 2024In a recent study out of Boehringer Ingelheim Animal Health USA Inc. in North Brunswick, New Jersey, scientists investigated cloruson and its related substances using an original ion-paired reversed phase ultraperformance liquid chromatography (IP-UHPLC) method.