Gas Chromatography (GC)

Protease inhibitors are a class of anti-HIV drugs used in combination therapy to block replication of the HIV virus in a person's blood. It is important to monitor the levels of these drugs in the patient since resistance can develop at low levels and at high levels the drug can exhibit toxic effects.

Mini application notes summaries

In the concluding part of this series, the effects that column variability has on isothermal capillary gas chromatography is discussed and instrument calibration explored. The goal is to reduce the normal variability that occurs when working with multiple instruments and columns to ensure consistent results.

Pittcon 2005 - the 56th Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy - returned to the Orange County Convention Center, Orlando, Florida, 27 February-4 March 2005. This year's event hosted more than 900 instrument manufacturers and 1aboratory suppliers in more than 2300 booths. In addition to attending the exposition, the conferees were able to listen to numerous oral presentations, view more than 900 posters, check out 38 seminar rooms, or attend one of 150 short courses.

The authors discuss the issue of meeting the demands of regulatory compliance whilst ensuring good scientific practice. A number of requirements from 21 CFR Part 11 are cited to demonstrate the importance of applying the principles of risk analysis.

This month's installment of "Milestones in Chromatography" pays tribute to a true milestone in the evolution of chromatography: the introduction of the first successful GC instruments.

In this first of a two-part series, John Hinshaw discusses the relative effects that inlet pressures and oven temperatures have on capillary gas chromatography.

This column focuses on some of the latest developments in preparative-scale columns, bulk packing materials and column hardware designs. Silica, polymeric and other packings are discussed together with the newest monolithic columns.

This instalment of GC Connections examines the basics of peak identification and quantification and demonstrates how they can both influence the quality of one's results as much as or even more than sample preparation, separation and detection.

Maltodextrin is an easily digested carbohydrate made from corn starch...

VENTURE A affinity columns utilize ICEtechTM surface passivation technology...

Mini application note summaries...

Polymeric monolithic stationary phases offer an alternative to the classical microparticulate sorbents...

In response to a reader's question, John Hinshaw examines the effects on retention times and peak shapes when a retention gap is added to a capillary column.

This article is an adaptation of one written in the German publication Nachrichten aus der Chemie and discusses how gas chromatography instrumentation, columns and techniques have improved over the past 10–15 years, making even relatively new equipment obsolete for many applications. In particular, the authors look at how older equipment is unsuitable for fast GC, better trace analysis and comprehensive multidimensional GC.

A report on the meeting that took place in April this year in York.

The effects of adding a precolumn - or retention gap - to a capillary column are explored.

The authors discuss how the materials, construction, and design of gas regulators can affect the delivery of low-level reactive gas mixtures.

Following on from the above Pittcon report, this month's "GC Connections" provides information on recently introduced gas chromatography instruments and accessories.

In the final of this two-part series examining trends in column introductions at the recent Pittcon 2004, Ron Majors looks at gas chromatography columns, sample preparation products, hardware, accessories and kits for chromatography and sample preparation.

A selection of mini application note write-ups

GC column bleed has been postulated to be caused by "backbiting" of the siloxane chain and volatility of noncrosslinked oligimers...

In another of Ettre's historical examinations of the early days of gas chromatography, he discusses four major application fields in which the technique changed the way chemists perform analyses. These include hydrocarbon analysis, fatty acid analysis, flavour compounds and essential oils analysis, and environmental analysis. In addition, he also explains how GC helped in the evolution of liquid chromatography and in the development of the scientific industry.

Editor of LC–GC Europe, David Hills, reports on his findings from a GC users' survey conducted amongst a selection of LC–GC Europe readers.

In this month's "GC Connections," John Hinshaw reports on new gas chromatography instruments and accessories exhibited at the 55th Pittsburgh Conference.