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The quality of a gas chromatogram depends heavily on the quality of the separation and detection gases, among many other factors. In this month's instalment, "GC Connections" discusses ways in which chromatographers can ensure a safe working environment while delivering gases that are up to the requirements of the separations at hand, in the context of moving a laboratory to a new location. [ABSTRACT FROM AUTHOR]

Comprehensive two-dimensional gas chromatography (GC x GC) offers significant improvement for volatile chemical separation. Selecting suitable first (¹D) and second dimension (²D) columns normally requires consideration of the chemical composition of a sample. Replacing one of these dimensions with a two-column ensemble (for example, ¹D1 + ¹D2 for the ¹D column), provided with a pressure tuning makeup gas between them, varies the relative retentions of compounds before the modulation step according to the junction pressure. This makes it possible to alter the apparent polarity of the ¹D ensemble, and this alters peak positions in the 2D GC x GC space. This article presents an account of studies that suggest this offers potential for improved operation for a GC x GC laboratory. [ABSTRACT FROM AUTHOR]

The article focuses on the development of fast gas chromatography (GC) and its significance in the separation technology. It discusses the difference between fast GC and high speed separations, the use of GC simulation software including calculations needed for electronic pressure control and compound retention behavior.

The article offers information on a study on the comparison of the separation speed of gas chromatography (GC), liquid chromatography (LC), and supercritical fluid chromatography (SFC). Topics discussed include using the kinetic plot method neglecting differences in viscous heating or extra-column band broadening; obtaining fixed length kinetic plot curves; and role of thermodynamic resistance factor in LC.

A popular feature of The Chromatographic Society's Golden Jubilee publication was an article by Waters describing their heritage and setting out their contributions to the development of chromatography. In this special feature, some of the companies who are regular exhibitors at Society events answer questions on the current and future status of chromatography. [ABSTRACT FROM AUTHOR]

The article presents several terms related to gas chromatography. These include the Active flow technology, a concept that merge two types of column designs, the curtain flow technology and the parallel segmented flow. It notes the active site, a strong attracting site on the surface of chromatographic packing. It mentions the adsorption chromatography, a basic separation mode that relies on adsorption method to effect a separation.

Advantages of comprehensive two-dimensional gas chromatography (GCxGC) include increased peak capacity, improved resolution, and unique selectivity compared to conventional one-dimensional gas chromatography (1D GC). Despite the maturing status of the technique, there are still some outstanding issues that spark discussion and controversy. One of them is the sensitivity enhancement in GCxGC separations compared to conventional 1D separation. In this article, the sensitivity of two-dimensional gas chromatography coupled to two different detectors -- a time-of-flight mass spectrometer (GCxGCTOF- MS) and a flame ionization detector (GCxGC-FID) -- was compared to the sensitivity of conventional one-dimensional gas chromatography (GC-TOF-MS and GC-FID) by determining method detection limits (MDLs) for a series of different compounds with different polarities. [ABSTRACT FROM AUTHOR]

The article examines gas chromatography (GC) separations using long-distance running as a metaphor. It discusses the attributes shared by long-distance runs and chromatography separations, such as a long, narrow course and a chromatography column, runners and solute molecules, and segregation of runners into groups and the formation of discrete peaks. The basic elements of chromatography experiment, namely flow, diffusion, and retention, are explored.

The article focuses on the history and phase development trends of chiral capillary gas chromatography (GC) as of 2012. It provides a comparison of high performance liquid chromatography (HPLC) and GC chiral separations. It discusses how to choose the best stationary phase and how to use it for the optimum capability of chiral GC separations. Also described are examples of injection of big volumes of diluted sample using retention gaps, racemates' elution order reversal, and other applications.

This article reports the early development of a microfabricated comprehensive gas chromatography(GC) system suitable for the separation of volatile organic compounds (VOCs) and competitive for uses as a portable measurement device. Thus low-power device showed good separation performance for a small set of VOCs and sub-ng detection sensitivity to monoaromatics. Comprehensive GC separation was achieved by coupling the primary column to the secondary via a differential flow modulator. Preliminary results from the 2D separation of gas mixes of several of gas mixes of several VOCs in the ppm range are promising. [ABSTRACT FROM AUTHOR]

Two-dimensional gas chromatography (GCxGC) and GCxGC-time-of-flight (TOF)-mass spectrometry (MS) have received increasing attention as powerful techniques for separation and analysis of extremely complex mixtures. Over the past 20 years, solid-phase microextraction (SPME) has become a staple sample preparation technique for a large variety of GC analyses. With a few additional considerations, SPME is combined readily with GCxGC or GCxGC-TOF-MS to provide easily automated and solvent-free sample preparation. This combination provides up to six dimensions of separation power in analytical method development that can be used to provide the required selectivity or can cause unwanted selectivity through sample losses or slow kinetics. In this article, the combination of SPME with GCxGC and GCxGC-TOF-MS is discussed using mixtures of solvents as example analytes. Optimization of the injection process is emphasized, as extractions remain generally the same as in traditional SPME-GC. To ensure good peak shapes, the injection liner, carrier gas flow rate and column temperatures must be optimized carefully. The differences in carrier gas flow optimization between GCXGC with flame ionization detection and GCxGC-TOF-MS also are discussed. [ABSTRACT FROM AUTHOR]

Detectors are another link in the chain of signals that a chromatographic analysis generates. After separation, a detector transduces the chemical signals of eluted analytes to an electrical signal that is then recorded and measured. The identities and amounts of analytes are determined from this information. This month in "GC Connections", John Hinshaw examines the environment, set-up and operating conditions necessary to ensure high gas chromatography detector performance and reliability. [ABSTRACT FROM AUTHOR]

This month's instalment of "GC Connections" discusses factors that can help determine which type of liquid injection technique is appropriate for specific samples, including having to use existing inlet systems that are on-hand in the laboratory with samples for which they might not be ideally suited. [ABSTRACT FROM AUTHOR]

Capillary gas chromatography (GC) is a well-established separation technique. Rick Parmely reviews some of the capillary column basics by investigating a standard test mixture and observing some of the chromatographic effects that can affect peak response, peak shape and column bleed. He provides guidelines for obtaining the best performance from a capillary column. He discusses peak tailing, column overload, ghost peaks and column bleed and speculates on "when to give up." He concludes with a set of fundamental steps to be used in achieving better GC analyses. [ABSTRACT FROM AUTHOR]

Presents various application notes related to liquid chromatography and gas chromatography. Description of the separation of the racemate of a respiratory drug candidate in gram scale; Application for accurate polystyrenesulphonic acid with gas chromatography; Provision of a simple solid-phase extraction method for the extraction of basic drugs from biological samples.

The article presents information on new gas chromatography (GC) instruments and accessories exhibited at the 56th annual Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy, held from February 27, 2005 to March 4, 2005, at the Orange County Convention Center in Orlando, Florida. In contrast to the impressively large PerkinElmer Model 154, this year's new GC developments centred again around miniaturized or micro-sized separation technologies. SLS MicroTechnology GmbH showed a new version of their GCM-5000 gas chromatography module enhanced with a carbon nanotube coated column that they claim will be capable of producing fixed-gas separations similar to molecular sieves or other carbonaceous column packings and coatings. C2V showed pre-launch samples of a micro gas chromatograph based on gas-phase microfluidics.

This article discusses the contents of a gas chromatography method. A chromatography method consists of three major parts including sample preparation, component separation and data handling. A chromatography method should capture a snapshot of all the information that would be necessary to recreate the analysis at a later date. There will always be instrument dependent disparities in the contents of a method. Different instruments are controlled in different ways, and there is imperfect cross-model uniformity in the name, number, range and function of many instrument parameters. Modern data systems have the capability to provide much of the information and store it in appropriate places.

This report aims to provide information about many of the new separation consumables and accessory products that were displayed at Pittcon 2004 conference. The information is based upon manufacturers' responses to a questionnaire mailed in December 2003. The report discusses gas chromatography columns, sample preparation products, hardware, accessories and kits for chromatography and sample preparation. Eight companies contributed new Gas Chromatography column information for Pittcon 2004, and one company introduced a series of columns for analytical and preparative superficial fluid chromatography.

Focuses on separation efficiency of capillary gas chromatography, complemented by hardware and detectors. Complexity of resolution on any chromatographic phase; Exacerbation of compounds present at trace amounts; Use of selective element specific detectors for positive compound identification.

Focuses on coupled-column gas chromatography (GC) analysis. Exploitation of multi-column geometries to enhance separation power of GC; Expansion of capacity strategies for volatile and complex sample analysis; Development of additional multidimensional approaches in parallel.

Discusses solid-phase microextraction (SPME). Potential to reduce or eliminate solvent consumption; Various applications of SPME; Use of SPME in gas chromatography and liquid chromatography separations; Difference from solid-phase extraction; Advantages of SPME over other sample preparation and injection techniques.

Growing interest in the speciation of elements within environmental and clinical chemistry is resulting in the development of sophisticated analytical techniques. This paper discusses state-of-the-art gas chromatography hyphenations with optical and mass spectrometric detection for trace metal speciation analysis of organometallic compounds. Particular attention is given to the topics of large-volume injection, separation on capillary columns and ultrasensitive detection. [ABSTRACT FROM AUTHOR]

The article focuses on the advent of the heart-cutting multidimensional gas chromatography (MDGC) in a gas chromatography (GC) column for hydrocarbon fractions. It discusses the scope of two-dimensional (2D) GC and MDGC and the involvement of Deans switch concept, and use of efficient transfer devices like cryogenic modulators and flow modulators.

The first meeting in The Chromatographic Society's diamond anniversary year brought together world-renowned speakers alongside past presidents of the Society, delegates from academia and industry, and scientific instrument and technology companies at the Institute of Engineering and Technology in central London on 22 March 2016. The presentations included discussions on liquid chromatography (LC), supercritical fluid chromatography (SFC), and gas chromatography (GC) from both an academic and industrial perspective - providing excellent insight into the state-of-the-art in these techniques for the delegates. [ABSTRACT FROM AUTHOR]

The article offers the author's insights regarding the Chromatographic Society (ChromSoc) which focuses on gas chromatography (GC). Topics include the meeting of the organization in London, England about the growth in GC, the impact of separation science in the industry and on the quality of everything, and the benefits GC and liquid chromatograhy (LC).

Synthetic fused silica capillary tubing continues to be the material of choice for modern Gas Chromatography (GC) columns. In this application note, we examine dimensional specifications of GC tubing from a historical perspective and compare It to empirical data from current production runs. [ABSTRACT FROM AUTHOR]

Reports on the advantage of two-dimensional gas chromatography for separation of complex mixtures. Separation of the sample on a first capillary column; Distribution of sample molecules over a limited space; Optimization of the frequency of modulation.

The article discusses on a method of determining polychlorinated biphenyls in water and soil by gas chromatography/electron capture detector (GC-ECD) using the large volume splitless technique (LV-SL). The application of LV-SL to GC-ECD is validated for the determination of PCBs in soil and water samples. It is found that the LV-SL method is 20-30 times more sensitive than traditional GC-ECD in determing PCBs in soil and water.

This application note will demonstrate a GC-MS analysis of common polybrominated diphenyl ether (PBDE) congeners. An optimized method will allow the Clarus GC-MS to provide ample separation and high yields of all PBDE congeners. The extended mass range of the Clarus 500 MS and high-mass calibration will produce mass spectra with very high levels of accuracy. [ABSTRACT FROM AUTHOR]

The SuperPure SFC50 System is an automated instrument developed by Thar Technologies Inc. for supercritical fluid chromatography (SEC) or HPLC at semi-prep scale. The system is capable of separating chiral compounds and collecting pure enantiomers, with reliable, fast and reproducible results. The retention time and separation repeatability of the compound with different purities is excellent. The developed separation can be used for purity analysis for QA/QC on an analytical scale or on a preparative scale to separate batches of varying purity.