Nicholas H. Snow

In this installment, we will describe several modes of MS/MS detector operation.

Looking at the fundamental terminology and data analysis principles in benchtop GC–MS

The latest edition of “GC Connections” presents an annual review of new developments in the field of gas chromatography introduced in 2024–2025.

In this installment, we will review the fundamental terminology and data analysis principles in benchtop GC–MS. We will compare the three modes of analysis—full scan, extracted ion chromatograms, and selected ion monitoring—and see how each is used for quantitative and quantitative analysis.

In the third part of Nicholas Snow's series on splitless GC injections, he discusses techniques for setting up the inlet and connections for optimized injections.

In Part II of our exploration of splitless injection, we will see that it is a surprisingly complex process, and that it is difficult to understand because we cannot see what is happening during the injection process. For this discussion, we will think of the injection process as beginning with the syringe plunger being depressed and ending with the start of a temperature program in the column oven. In most splitless injections, this process requires 30 s to 1 min. There are several band broadening and focusing mechanisms that affect the peak shapes, widths, and heights resulting from splitless injection.

Everyone is talking about sustainability, and organizations are creating sustainability programs. But what does green chemistry really mean, and how does it apply to gas chromatography?

For trace quantitative analysis, the splitless technique is most used as an inlet capable of performing both split and splitless injections. In this and upcoming installments, we take a closer look at splitless injection.

In this article, we discuss the fundamentals of headspace extraction, including static versus dynamic extraction, establishing equilibrium in the vial, consequences of the partition coefficient, temperature, pressure, and transfer to the gas chromatograph.

In this installment, we examine trends in the use of sample preparation techniques through the lens of instrumental analysis by gas chromatography (GC) and GC–mass spectrometry (GC–MS).

Pittcon convened in sunny San Diego, California, from February 24–28, 2024, and continued the trend of trade shows becoming smaller over the past several years.

In this installment, we examine several of the common parameters that can affect automated peak integration and the resulting peak areas. We will consider how the data system detects the beginning and end of the peak, how it determines the peak maximum, how real peaks are differentiated from noise, and how signals at individual time intervals are summed to generate the peak area.

Gas chromatography is a premier technique for quantitative analysis. As gas chromatographs have become simpler to use and data systems more powerful, much of the data processing involved in delivering quantitative results now happens in the background and is seemingly invisible to the user. In this installment, we will review the calibration techniques used with gas chromatography. We will compare calibration methods and the assumptions that underlie them. We will explore common mistakes and challenges in developing quantitative methods and conclude with recommendations for appropriate calibration methods for quantitative problems.

A recent sample preparation survey explored the critical role of sample preparation in gas chromatographic analysis.

Although not as common as in HPLC, molecular spectroscopy can be used with GC as well.

Gas chromatography can be used in combination with molecular spectroscopy to provide structural and quantitative information on a variety of sample types.

Comprehensive two-dimensional GC×GC has made great strides in the past 20 years. The author discusses advances in instrumentation, column sets, data analysis, and the range and types of samples amenable to this method.

Recent developments in GC×GC that make it more amenable for routine use are discussed.

We offer troubleshooting tips for various gas chromatography (GC) detectors, as well as provide an overview of the different options chromatographers have when using a GC detector.

This instalment explores the challenges involved in detecting the effluent from a capillary gas chromatographic column and summarizes the many detector options.

Separation scientists could strengthen their scientific work by practicing skills commonly associated with the liberal arts.

Exploring the impact of green chemistry on analytical chemistry and GC is the focus of this instalment of "GC Connections".

Everyone is talking about sustainability, and organizations are creating sustainability programs. But what does green chemistry really mean, and how does it apply to gas chromatography?

We assess the landscape of new gas chromatography (GC) instrumentation, supplies, and accessories introduced over the past 12 months.

"GC Connections" presents the column's annual review of new developments made in the field of gas chromatography, made available in 2022–2023.

This article provides a look at the new GC products that entered the market in 2022–2023.

Pittcon 2023 revealed that gas chromatography (GC) still has a strong presence at in-person conferences and in literature.

Understanding the relationship between selectivity and retention is key to realizing excellent gas chromatographic separations.

What is the relationship between selectivity and resolution?

By reviewing the basic thermodynamics underlying GC separations, we see how it impacts retention and method development in GC analysis.