Liquid Chromatography (LC/HPLC)

James P. Grinias is an Associate Professor in the Department of Chemistry & Biochemistry at Rowan University in Glassboro, New Jersey, and the winner of the 2022 Emerging Leader in Chromatography Award, which is presented by LCGC magazine.

A kinetic plot is a powerful tool, but how do you construct one—from either experimental data or data from other sources? We explain.

New developments in metal-organic frameworks (MOFs) for LC seek to control MOF distribution on the silica surface, improve understanding of the role of the substrate, and enhance robustness and reproducibility.

HPLC is emerging as the preferred analytical method for potency testing of cannabinoids, but fundamental work is needed to solve critical issues and contribute to advancing knowledge.

Barry L. Karger and James P. Grinias are the winners of the 15th annual LCGC Lifetime Achievement and Emerging Leader in Chromatography Awards, respectively, for 2022. Here, we review their achievements.

A HPLC method was developed to measure trimethylamine in fish oil supplements, to determine if the level of this compound affects product quality attributes such as rancidity.

The presence of per- and polyfluoroalkyl substances (PFAS) in products used every day by millions of people is a cause of concern among both consumers and scientists. PFAS found in drinking water and the environment can cause serious health issues in animals and humans. Amanda Belunis, who is a PhD candidate at the University of Maryland in Baltimore County, has been investigating the use of liquid chromatography­­–tandem mass spectrometry (LC–MS/MS) to detect PFAS from a variety of environmental sources. She spoke with us about methods used to detect PFAS and described a new method that she and her team have developed to enhance PFAS detection.

Kinetic plots can help us understand how different combinations of parameters will perform in relation the time needed to acquire a particular column efficiency—and thus resolution.

QuEChERS has been updated to suit modern instrumentation. Now also “efficient and robust,” QuEChERSER is a “mega-method” that covers a wider polarity range.

We review different approaches and coupling strategies for analyzing monoclonal antibody aggregates with 2D-LC.

Compact instrumentation offers important advantages for many workflows, as illustrated by these examples.

Errors arising from the DNPH approach commonly used to analyze carbonyl compounds in smoke from heat-not-burn (HNB) tobacco can be avoided by using the approach described in this study.

Are we ready to let software and instruments take over the art of separations?

Here, a new automated active pharmaceutical ingredient (API) extraction platform is integrated with online liquid chromatography (LC) to assess drug product potency. The platform dissolves the tablet coating (if present), disintegrates the tablet, and disperses and solubilizes the tablet for analysis.

Deviations from the expected pressure in modern LC systems (too low, too high, or fluctuating) can be diagnosed and more quickly resolved using the streamlined troubleshooting practices shown here.

In this month’s blog, we provide information about the Subdivision on Chromatography and Separations Chemistry (SCSC) of the Analytical Division of the American Chemical Society (ACS), sharing our main goals and introducing our newly appointed executive board members.

An improved LC–MS/MS method that can rapidly detect fipronil, an insecticide harmful to human health, is presented here for chicken eggs, feed, and soil.

With modern chromatography modeling software, is it time to hang up our laboratory coats? Is resistance to software solving separations futile?

The UHPLC–MS/MS method can accurately determine the presence of these illegal feed additives in swine tissues.

Improved analysis of pharmaceutical and natural medicine products requires advances in reversed-phase LC stationary phases. We examine two synthesized stationary phases with applicability in quality control and chiral separation for analysis of natural products.

GC and TLC methods are demonstrated for quantification of stigmasterol 3-O-β-D-glucopyranoside (S3G), the main active component in the herbal nutraceutical Balanites aegyptiaca, an antihyperglycemic in Egyptian folk medicine.

This article discusses the development of a series of applications that will allow for the determination of a number of nitrosamines that have been identified by the FDA as genotoxins to monitor, initially showing how to perform a separation of these compounds from the API and then looking at how MS can be applied to the analysis to ensure that the required detection limits can be reached.

In recent articles, the authors reviewed the basic concepts of extracolumn dispersion and how this phenomenon can impact the quality of an LC separation. We now specifically discuss the effects of dispersion that can occur due to tubing and detectors.

Recent developments in open-tubular liquid chromatography (OTLC) are explored with an emphasis on advances in column technology.

The more polar analyte will favour aqueous solvents, and the less polar will be more highly soluble in organic solvent—so which do we choose?

Ensuring complete overlapping (coelution) of analyte and internal standard peaks can be critical for eliminating matrix effects in LC–MS/MS analysis.

I do not believe in classic linear separations anymore—further, I think separations science is wildly underdeveloped and under-appreciated.

Reducing the column inner diameter results in a reduction in chromatographic dilution and increased sensitivity, allowing for more efficient tandem mass spectrometry sampling (MS/MS) and a higher number of molecule identifications.

Dispersion of analyte peaks outside of chromatography columns can seriously erode the resolution provided by good columns. Here, we focus on the contribution of the sample injection step to the total level of extracolumn dispersion in an LC system.

The effects of water on retention and selectivity in gas–solid chromatography of various adsorbent PLOT columns is reviewed.