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Determination of Semivolatile Organic Compounds in Drinking Water Using the Agilent 5977A Series GC-MSD

A method has been developed on the Agilent 5977A Series GC/MSD for the detection of 30 SVOCs at levels as low as 5 parts per billion (ppb), with excellent linearity (R2 > 0.990) and reproducibility (most relative standard deviations (RSDs) ~3.1%). 

 
 

GC Solutions

GC solutions #37: Inlet Liners – Part 2

In this issue we continue the discussion of inlet liners with a focus on liner outer diameter.

 

GC Solutions #38: Inlet Liners – Part 3

This month we continue our liner discussion with a focus on liner volume.

 

GC Solutions #36: Inlet Liners – Part 1

Selecting an appropriate inlet liner from the myriad available liner choices is a daunting task, especially when there is little qualified technical information about what differentiates them in terms of actual performance. This month we start discussing aspects of GC inlet liner design and associated selection criteria.

 

GC Solutions #35: Activity and Decomposition

Although gas chromatography has many positive attributes as an analytical tool, its incompatibility with labile and active compounds is certainly one of its biggest weaknesses. This month we discuss evidence of sample decomposition and what we might do to improve the results.

 

GC Solutions #34: Split Sample Introduction – Part 2: Measuring Flows, Liner Choice

Continuing our saga of split sample introduction, this month we discuss measuring gas flows and liner selection for split injections.

 

GC Solutions #33: Split Sample Introduction – Part 1: Background and Split Ratio

Anyone who analyzes samples by capillary gas chromatography has most likely used a split inlet. Although simple in concept, there are a few things to keep in mind to get the best analytical results possible.

 

GC Solutions #32: Saturation of GC Detectors

I recently received a question relating to the saturation of GC detectors. The GC user was unsure of the causes of saturation, what effect saturation might have on analytical results, how to know when it is happening, and how to avoid it.

 

GC Solutions #31: Hydrogen vs. Helium as Carrier Gas – Hot Discussions

There has been a recent surge in discussions amongst gas chromatographers about switching from helium to hydrogen for carrier gas. Most GC manufacturers, column suppliers, and suppliers of bottled gases and/or gas generators have been feeding the discussions (mostly in a positive, informative way) through publications, webinars, and/or advertising pushes.  So what prompted the current fervor and where is it headed?

 

GC Solutions #30: Pay Attention to Acquisition Rate and Detector Range

Last month we talked about determining limit of detection (LOD) and limit of quantitation (LOQ). I mentioned that it is important to pay attention to the detector acquisition rate and amplifier settings (if they are adjustable) since these can impact the ability to detect small peaks. This month we look at the impact of those factors in more detail.

 

GC Solutions #29: How do I Determine Limits of Detection and Quantification?

I received this question from Ask the Doctor . “I am doing some research trying to quantify an illicit drug using external calibration and I was wondering if you could help me understand the best way I can obtain my limit of detection and quantification? I was unable to run blank samples. Is that the only way? Really confused.”

 

GC Solutions #28: Why Don’t More People do Fast GC?

In this article I discuss the dichotomy between the often touted benefits of fast GC methods and the proportion of GC methods actually in use.

 

GC Solutions #26: Too Fast GC -- What is Too Fast in GC?

Commercialization of technologies to produce faster temperature ramps in GC have been some of the few GC advances in recent decades. This article will take a look at the utility and ultimate areas of practical application for these technologies.

 

GC Solutions #25: Is it Working?

This month we talk about avoiding problems through routine maintenance and verifying that your instrument is working through the use of a performance verification method.

 

GC Solutions #24: What’s New?

As I prepare to attend PittCon 2012, I suspect that the answer to the question “what’s new in gas chromatography?” is “not much”. Is that because there is nothing left for instrument manufacturers and researchers to do in the area or is there something else going on?

 

GC Solutions #23: Sandwich Injections

In this article we discuss the merits and deficiencies of sandwich injection techniques.

 

GC Solutions #22: Inlet Activity

In this article we discuss issues related to inlet and liner activity. 

 

GC Solutions #19: Calibration Curves – Part 1

In this article we discuss general approaches to GC response calibration and focus on the simplest; external calibration.

 

GC Solutions #16: Uncoated Pre-Column Backflush Configuration

Under discussion is one of the newer approaches to capillary column backflush: the uncoated pre-column configuration.

 

GC Solutions #15: Coated Pre-Column Backflush

Continuing our discussion of the three configurations of capillary column backflush, we cover the coated pre-column configuration.

 

GC Solutions #14: Post Column Backflush

We continue last month’s backflush discussion with a description of the most common form of backflush: post-column backflush. 

 

GC Solutions #13: Capillary Column Backflush

In this article we introduce the concepts of backflushing capillary columns.

 

GC Solutions #12: The Flame Ionization Detector – Part 2

Continuing the previous discussion of the most popular GC detector, the FID, we cover deviations from typical unit carbon response, optimization and troubleshooting.

 

GC Solutions #11: The Flame Ionization Detector

In this article we initiate a discussion on the workhorse detector of gas chromatography: the flame ionization detector.

 

GC Solutions #10: Basis of Interactions in Gas Chromatography – Part 3: Stationary Phase Selectivity, Glass Half Full?

In Part 3 we bring together the retention mechanism concepts discussed earlier to form a simple view of the nature of selectivity in liquid stationary phases used in gas chromatography.

 

GC Solutions #9: Basis of Interactions in Gas Chromatography – Part 2: Polar Interactions

To fully grasp the concepts of retention and selectivity of GC stationary phases, one must first understand the fundamental intermolecular interactions that lead to retention. This month we discuss polar interactions; the interactions responsible for any observed selectivity in GC.

 

GC Solutions #8: Basis of Interactions in Gas Chromatography, Part 1 – Non-Polar Interactions

To fully grasp the concepts of retention and selectivity of GC stationary phases, one must first understand the fundamental intermolecular interactions that lead to retention. In this article we discuss the most dominant of those interactions – dispersive, non-polar interactions.

 

GC Solutions #7: Hot Split Injections, Part 3 – Decomposition

In this article, we tackle another potential problem of hot split injection: sample decomposition. Decomposition changes the nature of components in the original sample, affecting the “recovery” of target compounds. 

 

GC Solutions #6: Hot Split Injections, Part 2 – Sources of Discrimination

This article continues our discussion of the process of hot split injection; the most popular form of sample introduction into capillary columns.

 

GC Solutions #5: Hot Split Injections – Part 1

This  article will discuss split injections with a hot split/splitless inlet. This is the most popular inlet and sampling mode for capillary GC. 

 

GC Solutions #4: GC Detectors

This article presents an overview of GC detectors.

 

GC Solutions #3: The Function of GC Columns

This month I present a general overview of the purpose of GC columns, key processes involved and high-level description of differences between them.

 

GC Solutions #2: The Function of GC Inlets

This article will cover the general function of GC inlets describing some common attributes and differences. It will also provide a context for future articles covering inlets in more detail.

 

GC Solutions #1: Helping You Get the Most Out of GC Analysis

In the monthly series of articles that will follow in GC Solutions I aspire to make the time you spend as rewarding as possible by presenting concise, clear, straightforward and practical articles on gas chromatographic (GC) analysis.

 
 

GC Solutions

 

GC Solutions #33: Split Sample Introduction – Part 1: Background and Split Ratio

Anyone who analyzes samples by capillary gas chromatography has most likely used a split inlet. Although simple in concept, there are a few things to keep in mind to get the best analytical results possible.

 

GC Solutions #34: Split Sample Introduction – Part 2: Measuring Flows, Liner Choice

Continuing our saga of split sample introduction, this month we discuss measuring gas flows and liner selection for split injections.

 

GC Solutions #36: Inlet Liners – Part 1

Selecting an appropriate inlet liner from the myriad available liner choices is a daunting task, especially when there is little qualified technical information about what differentiates them in terms of actual performance. This month we start discussing aspects of GC inlet liner design and associated selection criteria.

 

GC Solutions #35: Activity and Decomposition

Although gas chromatography has many positive attributes as an analytical tool, its incompatibility with labile and active compounds is certainly one of its biggest weaknesses. This month we discuss evidence of sample decomposition and what we might do to improve the results.