Liquid Chromatography (LC/HPLC)

This article describes the use of ultrahigh-pressure liquid chromatography (UHPLC) in pharmaceutical analysis of drug substances and drug products with UV absorption detection.

Getting started on the right foot is important for efficient method development.

The laboratory life science and analytical instrument industry is comprised of a large, diverse group of organizations that manufacture and distribute their products worldwide. However, overall industry sales are concentrated among a small set of companies. Approximately 950 firms are included in the industry, but only about 100 companies have sales above $50 million.

This month's Technology Forum looks at the topic of HPLC/Chiral and the trends and issues surrounding it. Joining us for this discussion is Magali Curiel of Thar Technologies, Inc., Rich Cowman of JASCO, and Geoffrey Cox of Chiral Technologies.

In early 2007, a web-based HPLC columns survey was conducted. Current usage was compared to a 1997 survey.

The concept of membrane-controlled processes is widespread in nature. Nearly all biological mechanisms concerning mass transport and exchange are regulated by membrane barriers and a variety of technical and biotechnological applications have been devised based on this mechanism. Membrane applications in analytical chemistry are geared towards the enrichment of target substances from an aqueous solution or the separation of compounds from a complex matrix. This article describes membrane-assisted extraction processes to separate traces of polar pharmaceutical substances the so called emerging micropollutants from aqueous samples. Basic prospects and examples of membrane-supported extractions are presented.

High-performance liquid chromatography (HPLC) is a powerful tool for the enantioselective separation of chiral drugs. However, the selection of an appropriate chiral stationary phase (CSP) and suitable operating conditions is a bottleneck in method development and a time- and resource-consuming task. Multimodal screening of a small number of CSPs with broad enantiorecognition abilities has been recognized as the best strategy to achieve rapid and reliable separations of chiral compounds. This paper describes the generic screening strategy developed at Johnson & Johnson Pharmaceutical Research and Development (J&J PRD) to successfully develop enantioselective HPLC methods for chiral molecules of pharmaceutical interest.

lthough liquid chromatography (LC) is most commonly associated with analytical techniques that are found inside the laboratory, LC also has been used in industrial applications for separation of a wide range of products for decades. The technique recently has been applied to requirements in the pharmaceutical and biotechnology industries, both inside the laboratory and in industrial settings. With global sales of over $1.7 billion, the market for preparative LC has encountered a stellar growth over the past few years.

The topic of this month's instalment of "LC Troubleshooting" was prompted by a manuscript I recently reviewed and a question I received from a reader of this column. Both inputs related to the variability of retention times observed in liquid chromatography (LC) methods. Variable retention is a topic that has been touched on many times over the history of this column, sometimes just in passing and other times in depth. Yet, it seems to be a problem that keeps recurring, so I think it is worth considering again.

Different methods require different strategies.

The authors present a convenient, step-by-step process for accelerating LC conditions that takes into account changes to column length, diameter and particle size.

Although liquid chromatography (LC) is most commonly associated with analytical techniques that are found inside the laboratory, LC also has been used in industrial applications for separation of a wide range of products for decades.

Chiral technology has become a very important aspect for scientists involved in the pharmaceutical, chemical, and agricultural industries. The chiral enantiomers can have vitally different pharmacological effects in biological systems. In fact, the U.S. Food and Drug Administration mandates that only therapeutically active isomers must be introduced to the prescription drug market.

Peptide mapping is one of the preferred techniques for the comprehensive characterization of biopharmaceutical products and is often the analytical method of choice for studying a protein's primary structure.

In 1983, the brainchild of Ed Aster, President of Aster Publishing, and Tom Hager, an editor, a publication called LC-Liquid Chromatography and HPLC Magazine was christened.

The terms hydrophilic interaction liquid chromatography (HILIC) and aqueous normal phase (ANP) chromatography very often are used interchangeably.

I have to cede my seniority as an LCGC columnist to Ron Majors - he started several months before I did.

Over the years, LC instrumentation has undergone continuous development in pursuit of greater performance. More recently, the focus of progress has been on shorter run times, as a direct response to greater user demand to perform faster chromatographic analyses, particularly for their LC–MS applications. This has led to separations on short (30–50 mm) columns with a small internal diameter (i.d. ~2.0 mm), packed with small particle size phases (1.5–3.0 μm). The trend for smaller column particle size has now reached a practical limit on current hardware and innovative technological solutions for further gains in performance are required. Several manufacturers offer fast LC instruments designed for greater productivity, while maintaining low carryover, high sample capacity, resolution and reliability. With ultra-fast run times of under 1 minute, these companies have achieved increased throughput using contrasting technological approaches. Here we examine the background to this current trend,..

Is it more than meets the eye?

...it is important to acknowledge that environmental concerns can be more important than the economics of the reduction of solvent consumption.

This month's forum looks at the topic of liquid chromatography-mass spectroscopy and the trends and issues surrounding it. Ed Long, Strategic Marketing Manager at Thermo Fisher Scientific, Robert Cody, Mass Spec Product Manager at JEOL, and Michael Willett, PR Relations Officer at Bruker.

Evaporative light scattering detection (ELSD) is considered by many to be a universal detection method for HPLC because its response does not depend on the analyte containing a chromophoric moiety.

Detector selection for a method should be made on a case-by-case basis.

his article reveals the first liquid chromatography (LC) separations performed on a microfabricated pillar array column under pressure-driven conditions. The pillars were non-porous and produced using a Bosch-type deep reactive ion etch (DRIE) to pattern the surface of a silicon wafer and had a diameter of approximately 5 μm. Two different packing densities were compared: one similar to the packing density of a packed bed (external porosity of approximately 49%) and one similar to the packing density of monolithic columns (external porosity of approximately 70%).

LC-MS-MS has become a widely used technique for the fast and sensitive quantitation of small molecules. In this article, this approach has been extended to high-throughput quantitative LC-MS-MS analysis under GLP applications for a drug candidate in development from preclinical animal studies through clinical development.