
Unexpected results from calibration standards create confusion in a clinical liquid chromatography (LC) method.

Unexpected results from calibration standards create confusion in a clinical liquid chromatography (LC) method.

Readers’ questions regarding problems related to internal standard calibration of liquid chromatography methods are addressed.

This instalment provides an overview of modern practices of high-throughput purification to support small-molecule drug discovery. It describes the use of reversed-phase liquid chromatography (LC) and supercritical fluid chromatography (SFC) for purifying diverse samples in a centralized laboratory setting. A case study is used to illustrate the principles and rationales for selecting operating parameters for these applications. This is the first instalment of four articles on “Separation Science in Drug Development” to describe the modern practice of separation science in supporting small-molecule drug discovery and development.

The HPLC Troubleshooting app is designed to help beginner HPLC users with HPLC troubleshooting.

Temperature affects not only retention but also relative retention in gas chromatography (GC) and therefore, when we change temperature, we also change the selectivity of the separation. This is true as we alter the isothermal separation temperature, but also as we change the slope of the temperature program gradient.

Enhanced-fluidity liquids are organic solvents or organic–aqueous solvents mixed with high proportions of liquefied gases, such as carbon dioxide.

Introduction from the Guest Editor.

A liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI–MS–MS) method has been developed to determine multiple preservatives in cosmetics and personal care products.

The capabilities of enhanced-fluidity liquid chromatography for highly polar compounds is described and the value of using the entire continuum of 0–100% carbon dioxide solvent systems is discussed in terms of changes in mobile‑phase properties and applications.

A novel approach to enhancing the selectivity of ionizable compounds using superficially porous particles that are stable in a wider pH range is reported here.

Internal standard methods are used to improve the precision and accuracy of results where volume errors are difficult to predict and control. A systematic approach has been used to compare internal and external standard methods in high performance liquid chromatography (HPLC). The precision was determined at several different injection volumes for HPLC and ultrahigh‑pressure liquid chromatography (UHPLC), with two analyte and internal standard combinations. Precision using three methods of adding the internal standard to the analyte before final dilution was examined. The internal standard method outperformed external standard methods in all instances.


Click the title above to open the LCGC Asia Pacific June 2015 regular issue, Vol 18, No 2, in an interactive PDF format.

Click the title above to open the LCGC Europe June 2015 regular issue, Vol 28, No 6, in an interactive PDF format.

Click the title above to open the LCGC North America June 2015 regular issue, Vol 33 No 6, in an interactive PDF format.

Click the title above to open the LCGC North America June 2015 Application Notebook, Vol 33 No s6, in an interactive PDF format.

VUV Analytics (Texas, USA) has announced that Dr. Jean Andino of Arizona State University (Arizona, USA) is the recipient of their summer 2015 academic grant.




The CAMAG TLC-MS Interface allows for rapid and contamination-free elution of TLC/HPTLC zones with online transfer to any given HPLC-MS system. Depending on the MS, substances can be identified within a minute.


Stereoisomers of chiral compounds - two different forms (isomers) that are identical in composition but are non‑superimposable mirror images of one another - can have dramatically different effects in the human body making it important to ensure the purity of enantiomeric mixtures produced in drug development.

Gyula Vigh, Emeritus Professor of Chemistry and inaugural holder of the Gradipore Chair in Separation Science at Texas A&M, has been awarded the Arnold O. Beckman Award for Outstanding Scientific Achievements in the field of electrodriven separation techniques sponsored by Sciex Separations, a division of AB Sciex (Massachusetts, USA).

The 21st International Symposium on Separation Sciences (ISSS) will be held at the Grand Hotel Union in Ljubljana, Slovenia, from 30 June–3 July 2015.

VWR, a global distributor of analytical products headquartered in Pennsylvania, USA, has announced its acquisition of the analytical instrumentation manufacturer Hichrom Limited based in Berkshire, UK.

Researchers from the University of Toronto in Canada have developed a novel approach using digital microfluidics to analyze multiple steroid hormones in small tissue samples (1–10 mg) collected using core-needle biopsy (CNB) sampling.

Click the title above to open The Column May 22, 2015 Europe & Asia issue, Volume 11, Number 9, in an interactive PDF format.

Click the title above to open The Column May 22, 2015 North American issue, Volume 11, Number 9, in an interactive PDF format.

LCGC blogger Tony Taylor describes how to easily transfer column dimensions and particle morphology using three equations.