Author Archive

Troubleshooting GC Column Baseline Issues

Every GC analyst experiences baseline issues at some point in their career, whether the baseline is higher than normal, or it contains additional peaks/spikes, or becomes erratic and drifts up and down.  In order to fix the baseline issues you will need to determine the cause.   I hope that the information contained in this post, […]

How I clean a GC injection port

Recently I have been asked by several customers how to clean an injection port.  My initial answer is always the same, you should clean the injection port according to the manufacturer’s recommendations.  But what instructions do I provide when the injection port was manufactured by Restek?  I usually provide the same response but then I […]

Hydrocarbon Ranges of Natural Gas and Petroleum Products

Sometimes customers need to analyze natural gas and petroleum products, whether it is to confirm the purity of the product by looking for the impurities which may be present, or for an environmental reason such as a spill or leak.  In order to choose the correct GC column and reference standards, one needs to know […]

ProEZGC Chromatogram Modeler – there is much more to the program than just the Welcome Screen

When you log into the ProEZGC Chromatogram Modeler software, you will see the screen below, which is what I refer to as the Welcome Screen. This is the starting point for all, and unfortunately all some customers will think there is to the ProEZGC software.   For those of you who have used ProEZGC, you […]

How to select the correct Conversion Kit for your SPME Arrow fiber

Jason Herrington recently wrote a post titled SPME Arrow Configurations.  The last paragraph in this post stated: “One last talking point: We told you there is no free lunch when incorporating the SPME Arrow into your laboratory, because you will have to install a GC Inlet Conversion Kit. It is important to stress that the […]

Purge and Trap weldment installation

Sometimes we get asked by customers for clarification when installing/connecting a new or replacement weldment from their purge & trap autosampler to their Agilent GC’s split/splitless injection port. As a result, I wrote this post to assist those that may be new to this type of installation or those that simply could use a quick […]

Step-by-step instructions to easily, quickly and safely shut-down your GCs

In this current economy with stay-at-home recommendations/requirements due to the coronavirus, it has been unfortunate that many laboratories have been or will be forced to temporarily close their doors until the spread of the virus decreases enough that the stay-at-home orders are rescinded. If you find yourself in this distressing situation, sometimes it is difficult […]

GC compounds – poor peak shapes and missing peaks

One of the most common questions I am asked by customers is “Why is my peak shape so poor?” Another is “I do not see a peak for my compound, what should I do?” Sometimes they are developing a new method and have no experience with the compound(s) of interest; other times things worked well […]

Sampling and analysis of landfill gas / biogas, an overview

Lately it seems that the sampling and analysis of landfill gas / biogas is a popular topic among our customers.  When initially ask about the topic, I had an idea of what customers were trying to do, but didn’t really have a firm grasp on the topic.  As I dug deeper, I began to realize just […]

General (very general) guidelines to help meet GC detection limits.

Sometimes we (tech service) receive requests from customers who cannot meet detection limits when developing a new method or when trying to follow a current method. They ask for advice on how to meet these limits.  As a result, I decided to provide some (very) general guidelines that I would follow back-in-the-day when I would […]